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(For more resources on this subject, see here.) Provider—Consumer Contract In the JBI environment, the provider and consumer always interact based on a services model. A service interface is the common aspect between them. WSDL 1.1 and 2.0 are used to define the contract through the services interface. The following figure represents the two parts of the WSDL representation of a service: In the Abstract Model, WSDL describes the propagation of a message through a type system. A message has sequence and cardinality specified by its Message Exchange Pattern (MEP). A Message can be a Fault Message also. An MEP is associated with one or more messages using an Operation. An Interface can contain a single Operation or a group of Operations represented in an abstract fashion—independent of wire formats and transport protocols. An Interface in the Abstract Model is bound to a specific wire format and transport protocol via Binding. A Binding is associated with a network address in an Endpoint and a single Service in the concrete model aggregates multiple Endpoints implementing common interfaces. Detached Message Exchange JBI-based message exchange occurs between a Provider and Consumer in a detached fashion. This means, the Provider and Consumer never interact directly. In technical terms, they never share the same thread context of execution. Instead, the Provider and Consumer use JBI NMR as an intermediary. Thus, the Consumer sends a request message to the NMR. The NMR, using intelligent routers decides the best matched service provider and dispatches the message on behalf of the Consumer. The Provider component can be a different component or the same component as the Consumer itself. The Provider can be an SE or a BC and based on the type it will execute the business process by itself or delegate the actual processing to the remotely bound component. The response message is sent back to the NMR by the Provider, and the NMR in turn passes it back to the Consumer. This completes the message exchange. The following figure represents the JBI-based message exchange: There are multiple patterns by which messages are exchanged, which we will review shortly. Provider—Consumer Role Though a JBI component can function as a Consumer, a Provider, or as both a Consumer and Provider, there is clear cut distinction between the Provider and Consumer roles. These roles may be performed by bindings or engines, in any combination of the two. When a binding acts as a service Provider, an external service is implied. Similarly, when the binding acts as a service Consumer, an external Consumer is implied. In the same way, the use of a Service Engines in either role implies a local actor for that role. This is shown in the following figure: The Provider and Consumer interact with each other through the NMR. When they interact, they perform the distinct responsibilities (not necessarily in the same order). The following is the list of responsibilities, performed by the Provider and Consumer while interacting with NMR: Provider: Once deployed, the JBI activates the service provider endpoint. Provider: Provider then publishes the service description in WSDL format. Consumer: Consumer then discovers the required service. This can happen at design time (static binding) or run time (dynamic binding). Consumer: Invokes the queried service. Provider and Consumer: Send and respond to message exchanges according to the MEP, and state of the message exchange instance. Provider: Provides the service by responding to the function invocations. Provider and Consumer: Responds with status (fault or done) to complete the message exchange. During run-time activation, a service provider activates the actual services it provides, making them known to the NMR. It can now route service invocations to that service. javax.jbi.component.ComponentContext context ;// Initialized via. AOPjavax.jbi.messaging.DeliveryChannel channel = context. getDeliveryChannel();javax.jbi.servicedesc.ServiceEndpoint serviceEndpoint = null; if (service != null && endpoint != null) { serviceEndpoint = context.activateEndpoint (service, endpoint); } The Provider creates a WSDL described service available through an endpoint. As described in the Provider-Consumer contract, the service implements a WSDL-based interface, which is a collection of operations. The consumer creates a message exchange to send a message to invoke a particular service. Since consumers and providers only share the abstract service definition, they are decoupled from each other. Moreover, several services can implement the same WSDL interface. Hence, if a consumer sends a message for a particular interface, the JBI might find more than one endpoint conforming to the interface and can thus route to the best-fit endpoint. Message Exchange A message exchange is the "Message Packet" transferred between a consumer and a provider in a service invocation. It represents a container for normalized messages which are described by an exchange pattern. Thus message exchange encapsulates the following: Normalized message Message exchange metadata Message exchange state Thus, message exchange is the JBI local portion of a service invocation. Service Invocation An end-to-end interaction between a service consumer and a service provider is a service invocation. Service consumers employ one or more service invocation patterns. Service invocation through a JBI infrastructure is based on a 'pull' model, where a component accepts message exchange instances when it is ready. Thus, once a message exchange instance is created, it is sent back and forth between the two participating components, and this continues till the status of the message exchange instance is either set to 'done' or 'error', and sent one last time between the two components. Message Exchange Patterns (MEP) Service consumers interact with service providers for message exchange employing one or more service invocation patterns. The MEP defines the names, sequence, and cardinality of messages in an exchange. There are many service invocation patterns, and, from a JBI perspective, any JBI-compliant ESB implementation must support the following four service invocations: One-Way: Service consumer issues a request to the service provider. No error (fault) path is provided. Reliable One-Way: Service consumer issues a request to the service provider. Provider may respond with a fault if it fails to process the request. Request-Response: Service Consumer issues a request to the service provider, with expectation of response. Provider may respond with a fault if it fails to process request. Request Optional-Response: Service consumer issues a request to the service provider, which may result in a response. Both consumer and provider have the option of generating a fault in response to a message received during the interaction. The above service invocations can be mapped to four different MEPs that are listed as follows. In-Only MEP In-Only MEP is used for one-way exchanges. The following figure diagrammatically explains the In-Only MEP: In the In-Only MEP normal scenario, the sequence of operations is as follows: Service Consumer initiates with a message. Service Provider responds with the status to complete the message exchange. In the In-Only MEP normal scenario, since the Consumer issues a request to the Provider with no error (fault) path, any errors at the Provider-level will not be propagated to the Consumer.    

Overview of the D-Cube In Analyst, data is stored in a D-Cube. The D-Cube is a multi-dimensional data structure similar to an OLAP or Excel pivot table. Each of the dimensions contains a list of related data. For example, in a four dimensional cube, the first dimension may contain the items in  P&L statement, the second may list the departments, the third show the timescale, and the fourth may show the version (Budget or Actual). In this example, you have the  P&L statement by month, by department, and by version. The D-Cube must have at least two dimensions. If more than two dimensions exist, the other dimensions appear as pages. The following screenshot depicts a four dimensional D-Cube. The first two dimensions form the rows and columns. The third and fourth dimensions are displayed as pages, in the upper-left corner of the D-Cube. You can switch to different pages in the cube by clicking the page drop-down list and selecting another page. Creating a D-Cube Creating a D-Cube takes a few simple steps but it requires a great deal of forethought. Before creating the D-Cube, you must think through the dimensions that will form the cube. You must know what data will populate the D-Cube. You must know what category of D-Lists your selection falls under so that you can prioritize the calculations appropriately. You must know what function the D-Cube performs. Is it an input cube, a calculation cube, a summary or reporting cube, or a staging cube? You must also know in which library the D-Cube will be stored, and whether the D-Cube will be shared or will be exclusive to a model. Finally, you must consider size and performance, especially if you plan to deploy the D-Cube in Contributor. To create a D-Cube: Click on File | New | D-Cube. In the Create new D-Cube box, select the D-List that makes up the D-Cube. Drop the D-List onto the lower pane. Order the D-List. Click on OK. Enter the D-Cube name, and then click on OK. By default, the D-Cube opens with the longest D-List as the rows and the timescale as the columns. You can transpose the cube or swap the dimensions by dragging and dropping them. When you close and reopen the D-Cube, it will revert to the default view. Order of dimensions It is important to have the proper order of dimensions in the D-Cube. The order of dimensions is important because it determines which calculation takes precedence when calculations from two separate D-Lists intersect. The order also determines the priority of formats when the cell has opposing formats. As a rule, the dimensions must follow this order: Calculation: Calculation D-Lists contain mathematical operations over and above simple addition. Any use of operators, such as multiplication, subtraction, division, or the use of a BiF, make the D-List a calculation D-List. Aggregation: Aggregation D-Lists usually contain a hierarchy of items, such as an organizational hierarchy, a list of products, customers, or cost centers, or a list of items with a simple subtotal. Non-Calculating: Non-Calculating D-Lists contain no calculations. Timescale: Timescale D-Lists contains items that span a period of time, such as months, weeks, or days. Versions: Version D-Lists contain iterations of the data, such as Actual, Budget, Forecast, and Revised Budget. It is critical to set the proper order of dimensions before building the Contributor application. If you reorder the dimensions after the application is created, all of the data in the D-Cube will be deleted. In addition, reordering dimensions changes the structure of the import tables and, therefore, the way that you import data into Contributor. Size considerations The size of the D-Cube is measured by the number of cells in it. The number of cells you can have in a D-Cube is limited only by your computer's memory. When you build a D-Cube, you should keep in mind the amount of memory available on the computer on which the model will be used. You will not be able to open a large cube if your PC does not have enough memory to handle the data. If the model is deployed in Contributor, size is an even more important consideration. Even with a powerful computer, you will experience performance lag because a large model must pass through the organization's network. In a wide area network, the problem associated with a large model becomes more apparent. To determine the number of cells, find the product of the number of items in all of the D-lists in the D-Cube. For instance, if a D-Cube has five D-Lists, which have the following number of items: 8, 1, 10, 5, and 12, the number of cells in the D-Cube will be 4,800. This is 8*1*10*5*12. You can find the number of cells in the dimension selection box, as illustrated in the following screenshot: The number of items in a dimension has an inverse impact on the magnitude of size increases for additions to the cube. The fewer the items, the bigger the impact that an addition will have to the size of the cube. In the example of the cube above, if you add one item to a dimension that has only one item, you will double the size of the cube. However, if you add one item to a dimension that has 10 items, you will increase the size of the cube by only ten percent. One clue that your D-Cube may have a problem with size is the number of dimensions. While there is no limitation on the number of dimensions that a cube can have, having too many of them can become a problem. With a D-Cube that has too many dimensions, any additional item in one of the D-Lists increases the size in an order of magnitude depending on the number of items in the D-List. If possible, keep the number of dimensions to not more than five. If you need to have a D-Cube that provides views of data beyond five dimensions, consider splitting the D-Cube. You are more likely to require less memory if you have several smaller cubes than with one super cube. With Analyst, you can open a D-Cube that has several million cells on a PC that has 512MB of RAM. However, if you plan to deploy the model in Contributor, the threshold for the number of cells is much lower. An acceptable benchmark is roughly 500,000 cells per e.List. This benchmark is subject to many other factors, such as network latency, client PC memory, and CPU, all of which can contribute to model performance. Working with the D-Cube When working with the D-Cube, you have several functionalities that help you to hone in on the information that you want. By default, the D-Cube opens in full view, but you can open only a slice of the cube and save the slice for later viewing. Opening a full view of the D-Cube The most straightforward way to view the D-Cube is to open all dimensions. To open a full D-Cube: Click on File | Open | D-Cube. Select the D-Cube. Click on OK. Select the Full option. Click on OK. Opening a selection of the D-Cube A selection is a subset of a D-Cube. You can only open the specific items of the dimensions that you want to view. Because the data in a selection is fewer than the full view, less memory is required and the D-Cube opens and recalculates faster. To open a selection of the D-Cube: Click on File | Open | D-Cube. Select the D-Cube. Click on OK. Select the Edit Selection option. This option opens the dimension selection box, where you can select the items that you want to view in the D-Cube slice. As shown in the following illustration, the item selection box lets you select the items from a dimension that you want to include in your view. In the item selection box, each tab represents a D-List. To select the items, move the items from the Items available pane (on the left) to the Items included pane (on the right). Click on OK. Viewing different slices of the D-Cube You can view the D-Cube in a variety of ways. You can open a selection of the D-Cube, or several selections at the same time. If you have a selection open, you can change it to another selection. The ability to switch views makes it easier to work with the D-Cube. For instance, suppose you have a D-Cube that has two versions: Budget and Actual. If you want to enter only budget data, you may want to open only the Budget dimension and keep the Actual dimension closed. You can have multiple selections of the D-Cube open at the same time in the same way that you open the D-Cube. This allows you to arrange the selections next to each other on the same screen. To modify the views of the D-Cube: With the D-Cube open, click on D-CubeSelections: New Slice: This option allows you to create a new view of the same D-Cube, with the same selection. Reselect: Modify the current selection. Selecting this option allows you to add or remove dimensions in the current view. Save: Save the current selection as a saved selection. This option allows you to save the current view so that you can open it again later. If you select Reselect, move the items that you want to add to or remove from the current view from the Items included to the Items available pane, or vice versa, respectively. Click on OK. Saving a selection You can select a view of a D-Cube and then save this selection so that you do not have to reselect the same view the next time that you open the cube. When you save a selection, you create a "saved selection"—an object that is derived from the cube. To save a selection: Click File | Open | D-Cube. Select the D-Cube. Under Mode, select Edit Selection. Select the D-List items that you want to view in the D-Cube, and move them from the Items available pane to the Items included pane. If you do not select anything in the Items available pane, then all of the items will be included in the selection, including any future additions to the D-List. Under the Save Selections option on the lower-right corner of the dialog box, click on the Save button. Enter the name of the saved selection. Click on OK. If you have a saved selection, you can load it into the item selection box. The dimension item selection box is used in many functions, including export, D-List imports, and D-Cube allocations (to be discussed later). Opening the saved selection Once saved, the selection becomes a separate object that can be copied and shared. However, because it is a subset of the cube, you have to go through the cube to access the saved selection. To open the saved selection: Click on File | Open | D-Cube. Select the D-Cube. Under Mode, select Saved Selection. Select the Saved Selection. Click on OK    

Maintaining content As you continue to add content to your web site, you will need to ensure that your content is properly moderated, that old content is removed, and that changes to web site content are tracked. Creating content revisions Good Eatin' Goal: Create revisions of content to ensure that you have a complete record of changes to your web site's content. Additional modules needed: None. Basic steps We have simply updated our pages as necessary to add new functionality and content. However, if you have many editors, content that changes frequently, a need to view the history of a page, or need the ability to easily return to an old version of a page, you will want to store multiple revisions of your pages. To do this, carry out the following steps: Edit the content for which you want to create a new revision. Make the changes as needed and, before saving, expand the Revision information section. Select the Create new revision option and enter a message describing the changes that you have made to the node. When you save the content, you will see a new tab called Revisions. Clicking on this tab will show you a list of all of the revisions that have been created for the page. If you would like to return to an older version of the page, you can click the revert link. Or, if you want to remove an older revision, you can click the delete link to get rid of it permanently. You can control which users have access to the revision system by using the Permissions Manager. Drupal allows you to control which users can: view revisions, revert revisions, and delete revisions. If you want to force users to always create new revisions when editing content, edit the content type and then expand the Workflow settings. Change the default options to select the Create new revision option. When editors change content, the Create new revision option will be selected by default, and they will not be able to change the option unless they have the administer nodes permission. If you want to approve all revisions before publication, you can deselect the Published checkbox. Comparing content revisions Good Eatin' Goal: Compare the text of two different revisions of a page. Additional modules needed: Diff (http://drupal.org/project/diff). Basic steps Although the built-in functionality for creating revisions in Drupal works perfectly well, it can be difficult to review the changes that were made in each revision. The Diff module makes comparing revisions very easy. Begin by installing and activating the Diff module. To use the Diff module, simply view the revisions for any page. You will notice that the Revisions list has changed to allow you to select the revisions to be compared. Select the revisions to compare and then click on the Show diff button. Drupal will then display information about the text that has been changed, added, or deleted. Moderate content Good Eatin' Goal: Find questionable or offensive content, and remove it from your site, easily. Additional modules needed: Modr8 (http://drupal.org/project/modr8). Basic steps An unfortunate side effect of having a web site on the Internet is that, at some point, a malicious user will attempt to post inappropriate content on your site. If your site is extremely busy, you may find yourself with a large amount of content to review and approve. The Modr8 module can help you manage the workload and can send emails to users letting them know when their content has been approved or rejected. Begin by installing and activating the Modr8 module. The settings for the Modr8 module can be accessed by selecting Site configuration and then Modr8, from the Administer menu. The basic settings control how often logs are removed. Alternatively, you can choose to keep the logs forever. You can also change the number of items in the moderation queue to be displayed at a time, as well as the default action for the content that requires moderation. You can also configure the email settings for the moderation queue, including the text of the emails, and whether or not emails should be sent to the user who posted the content when their content is approved and/or when their content is rejected. You can also choose to send an email if the moderator does not take action for the item and wants to send a note to the author. If you would like new content to be added to the moderation queue automatically, you can edit the content type and select the In moderation queue setting in the workflow section. To view the moderation queue, select Content management and then Moderated content, from the Administer menu. The moderation queue appears as follows: From this page, you can approve, delete, or defer action on any content that needs moderation. After you make your changes, click Save to complete your selections. You can also display a log of all the moderation actions, by clicking on Reports and then Content moderation log. The moderation log appears as follows: Allowing users to report questionable or offensive content. Good Eatin' Goal: Get feedback from users to learn what they find offensive so the objectionable content can be removed. Additional modules needed: Abuse (http://drupal.org/project/abuse). Basic steps In the last task, we reviewed methods that allowed you to moderate every piece of content that is added to the site. However, this can be a time-intensive task if the proportion of content that you receive that is questionable is low. If this is the case, you can allow your users to help you to moderate the content by using the Abuse module, to let them report items that they find offensive. This strategy has a couple of advantages. Firstly, you are freed from the maintenance of pre-approving all content before it is published. Secondly, it ensures that the content meets community standards, rather than placing you or your editors in charge of defining community standards. The Abuse module also has a Watchlist component that allows you to flag content as suspicious or banned, and automatically move them into a queue for review by an administrator. Begin by downloading and installing the Abuse and Watchlist modules, both of which are included in the Abuse installation. We will begin by editing the Watchlist settings, which can be accessed by selecting Site configuration and then Watchlist settings, from the Administer menu. You can include any words that you want to, in the Watch list and Filtered/banned word list, depending on your target audience and your site's needs; just make sure that you enter one word per line. Items on the Watch list can be viewed while they are in the review queue, and items on the Filtered/banned word list will be hidden until they are reviewed. You can also control which items are automatically added to the Watch list or banned list, based on the Watchlist word settings configured above. You can also force moderation for specific types if they are more prone to abuse. We can now modify the Abuse Moderation settings by selecting Site configuration and then Abuse Moderation settings, from the Administer menu. The first setting controls what content types are subject to abuse reports. The next section of controls how abuse tickets are to be handled by your moderators. If you have multiple moderators for your site, you can select the Abuse Assigned Moderators option. If you use this, you will also need to store the maximum number of items that have been flagged for abuse that are added to the moderator's queue. If moderators live in different time zones, you can set an hour of the day at which all moderation queues are cleared, so that items do not remain in the moderation queue for an overly-long period of time. Finally, you can configure the settings related to all of the items that have been flagged as abusive by a user. The Abuse threshold controls how many complaints must be registered for an item before it is moved into the moderation queue. 3 is a good number to start with, but you may want to increase or decrease the threshold depending on the needs of your site. You can edit the reasons for flagging an item for abuse by selecting Site configuration, then Abuse Moderation settings, and finally Abuse Moderation reasons, from the Administer menu. All available reasons will be listed on the page using a format similar to the example above. You can add new reasons, remove reasons, or change the text for reasons from this page. Before the abuse module is activated, you need to assign permissions to users, so that they can flag content for review. Content that has the abuse module activated will have a new Flag as offensive link added to it, as shown in the following screenshot: When the user clicks on the Flag as offensive link, he or she will be presented with a form where he or she can specify their contact information, and a reason why he or she believes that the content is offensive. Administrators can review content that has been flagged as offensive by clicking on Content management and then Moderate. The administrators can click on the Get More Tickets link to have additional items assigned to them. Once a ticket has been assigned to them, the administrator can view information about the user who submitted the content as well as the user who flagged the content, and choose what action to take for the content. The administrator can either allow the content, or remove the content from the web site. The administrator can also optionally send a warning to the user without further action.

IT organizations are under increasing demand to increase the ability of the business to innovate while controlling and often reducing costs. Legacy modernization is a real opportunity for these goals to be achieved. To attain these goals, the organization needs to take full advantage of emerging advances in platform and software innovations, while leveraging the investment that has been made in the business processes within the legacy environment.To make good choices for a specific roadmap to modernization, the decision makers should work to have a good understanding of what these modernization options are, and how to get there. Overview of the Modernization Options There are five primary approaches to legacy modernization: Re-architecting to a new environment SOA integration and enablement Replatforming through re-hosting and automated migration Replacement with COTS solutions Data Modernization Other organizations may have different nomenclature for what they call each type of modernization, but any of these options can generally fit into one of these five categories. Each of the options can be carried out in concert with the others, or as a standalone effort. They are not mutually exclusive endeavors. Further, in a large modernization project, multiple approaches are often used for parts of the larger modernization initiative. The right mix of approaches is determined by the business needs driving the modernization, organization's risk tolerance and time constraints, the nature of the source environment and legacy applications. Where the applications no longer meet business needs and require significant changes, re-architecture might be the best way forward. On the other hand, for very large applications that mostly meet the business needs, SOA enablement or re-platforming might be lower risk options. You will notice that the first thing we talk about in this section—the Legacy Understanding phase—isn't listed as one of the modernization options. It is mentioned at this stage because it is a critical step that is done as a precursor to any option your organization chooses. Legacy Understanding Once we have identified our business drivers and the first steps in this process, we must understand what we have before we go ahead and modernize it. Legacy environments are very complex and quite often have little or no current documentation. This introduces a concept of analysis and discovery that is valuable for any modernization technique. Application Portfolio Analysis (APA) In order to make use of any modernization approach, the first step an organization must take is to carry out an APA of the current applications and their environment. This process has many names. You may hear terms such as Legacy Understanding, Application Re-learn, or Portfolio Understanding. All these activities provide a clear view of the current state of the computing environment. This process equips the organization with the information that it needs to identify the best areas for modernization. For example, this process can reveal process flows, data flows, how screens interact with transactions and programs, program complexity and maintainability metrics and can even generate pseudocode to re-document candidate business rules. Additionally, the physical repositories that are created as a result of the analysis can be used in the next stages of modernization, be it in SOA enablement, re-architecture, or re-platforming. Efforts are currently underway by the Object Management Group (OMG) to create a standard method to exchange this data between applications. The following screenshot shows the Legacy Portfolio Analysis: APA Macroanalysis The first form of APA analysis is a very high-level abstract view of the application environment. This level of analytics looks at the application in the context of the overall IT organization. Systems information is collected at a very high level. The key here is to understand which applications exist, how they interact, and what the identified value of the desired function is. With this type of analysis, organizations can manage overall modernization strategies and identify key applications that are good candidates for SOA integration, re-architecture, or re-platforming versus a replacement with Commercial Off-the-Shelf (COTS) applications. Data structures, program code, and technical characteristics are not analyzed here. The following macro-level process flow diagram was automatically generated from Relativity Technologies Modernization Workbench tool. Using this, the user can automatically get a view of the screen flows within a COBOL application. This is used to help identify candidate areas for modernization, areas of complexity, transfer of knowledge, or legacy system documentation. The key thing about these types of reports is that they are dynamic and automatically generated. The previous flow diagram illustrates some interesting points about the system that can be understood quickly by the analyst. Remember, this type of diagram is generated automatically, and can provide instant insight into the system with no prior knowledge. For example, we now have some basic information such as: MENSAT1.MENMAP1 is the main driver and is most likely a menu program. There are four called programs. Two programs have database interfaces. This is a simplistic view, but if you can imagine hundreds of programs in a visual perspective, we can quickly identify clusters of complexity, define potential subsystems, and do much more, all from an automated tool with visual navigation and powerful cross-referencing capabilities. This type of tool can also help to re-document existing legacy assets. APA Microanalysis The second type of portfolio analysis is APA microanalysis. This examines applications at the program level. This level of analysis can be used to understand things like program logic or candidate business rules for enablement, or business rule transformation. This process will also reveal things such as code complexity, data exchange schemas, and specific interaction within a screen flow. These are all critical when considering SOA integration, re-architecture, or a re-platforming project. The following are more models generated from the Relativity Modernization Technologies Workbench tool. The first is a COBOL transaction taken from a COBOL process. We are able to take a low-level view of a business rule slice taken from a COBOL program, and understand how this process flows. The particulars of this flow map diagram are not important; rather, this model can be automatically generated and is dynamic based on the current state of the code. The second model shows how a COBOL program interacts with a screen conversation. In this example, we are able to look at specific paragraphs within a particular program. We can identify specific CICS transaction and understand which paragraphs (or subroutines) are interacting with the database. The models can be used to further refine our drive for a more re-architected system, which helps us to  identify business rules and populate a rules engine, This example is just another example of a COBOL program that interacts with screens—shown in gray, and the paragraphs that execute CICS transactions—shown in white. So with these color coded boxes, we can quickly identify paragraphs, screens, databases, and CICS transactions. Application Portfolio Management (APM) APA is only a part of IT approach known as Application Portfolio Management. While APA analysis is critical for any modernization project, APM provides guideposts on how to combine the APA results, business assessment of the applications' strategic value and future needs, and IT infrastructure directions to come up with a long term application portfolio strategy and related technology targets to support it. It is often said that you cannot modernize that which you do not know. With APM, you can effectively manage change within an organization, understand the impact of change, and also manage its compliance. APM is a constant process, be it part of a modernization project or an organization's portfolio management and change control strategy. All applications are in a constant state of change. During any modernization, things are always in a state of flux. In a modernization project, legacy code is changed, new development is done (often in parallel), and data schemas are changed. When looking into APM tool offerings, consider products that can provide facilities to capture these kinds of changes in information and provide an active repository, rather than a static view. Ideally, these tools must adhere to emerging technical standards, like those being pioneered by  the OMG. Re-Architecturing Re-architecting is based on the concept that all legacy applications contain invaluable business logic and data relevant to the business, and these assets should be leveraged in the new system, rather than throwing it all out to rebuild from scratch. Since the new modern IT environment elevates a lot of this logic above the code using declarative models supported by BPM tools, ESBs, Business Rules engines, Data integration and access solutions, some of the original technical code can be replaced by these middleware tools to achieve greater agility. The following screenshot shows an example of a system after re-architecture. The previous example shows what a system would look like, from a higher level, after re-architecture. We see that this isn't a simple transformation of one code base to another in a one-to-one format. It is also much more than remediation and refactoring of the legacy code to standard java code. It is a system that fully leverages technologies suited for the required task, for example, leveraging Identity Management for security, business rules for core business, and BPEL for process flow. Thus, re-architecting focuses on recovering and reassembling the process relevant to business from a legacy application, while eliminating the technology-specific code. Here, we want to capture the value of the business process that is independent of the legacy code base, and move it into a different paradigm. Re-architecting is typically used to handle modernizations that involve changes in architecture, such as the introduction of object orientation and process-driven services. The advantage that re-architecting has over greenfield development is that re-architecting recognizes that there is information in the application code and surrounding artifacts (example, DDLs, COPYBOOKS, user training manuals) that is useful as a source for the re-architecting process, such as application process interaction, data models, and workflow. Re-architecting will usually go outside the source code of the legacy application to incorporate concepts like workflow and new functionality that were never part of the legacy application. However, it also recognized that this legacy application contains key business rules and processes that need to be harvested and brought forward. Some of the important considerations for maximizing re-use by extracting business rules from legacy applications as part of a re-architecture project include: Eliminate dead code, environmental specifics, resolve mutually exclusive logic. Identify key input/output data (parameters, screen input, DB and file records, and so on). Keep in mind many rules outside of code (for example, screen flow described in a training manual. Populate a data dictionary specific to application/industry context. Identify and tag rules based on transaction types and key data, policy parameters, key results (output data). Isolate rules into tracking repository. Combine automation and human review to track relationships, eliminate redundancies, classify and consolidate, add annotation. A parallel method of extracting knowledge from legacy applications uses modeling techniques, often based on UML. This method attempts to mine UML artifacts from the application code and related materials, and then create full-fledged models representing the complete application. Key considerations for mining models include: Convenient code representation helps to quickly filter out technical details. Allow user-selected artifacts to be quickly represented in UML entities. Allow user to add relationships and annotate the objects to assemble more complete UML model. Use external information if possible to refine use cases (screen flows) and activity diagrams—remember that some actors, flows, and so on may not appear in the code. Export to XML-based standard notation to facilitate refinement and forward-re-engineering through UML-based tools. Modernization with this method leverages the years of investment in the legacy code base, it is much less costly and less risky than starting a new application from ground zero. However, since it does involve change, it does have its risks. As a result, a number of other modernization options have been developed that involve less risk. The next set of modernization option provide a different set of benefits with respect to a fully re-architected SOA environment. The important thing is that these other techniques allow an organization to break the process of reaching the optimal modernization target into a series of phases that lower the overall risk of modernization for an organization. In the following figure, we can see that re-architecture takes a monolithic legacy system and applies technology and process to deliver a highly adaptable modern architecture. Since SOA integration is the least invasive approach to legacy application modernization, this technique allows legacy components to be used as part of an SOA infrastructure very quickly and with little risk. Further, it is often the first step in the larger modernization process. In this method, the source code remains mostly unchanged (we will talk more about that later) and the application is wrapped using SOA components, thus creating services that can be exposed and registered to an SOA management facility on a new platform, but are implemented via the exiting legacy code. The exposed services can then be re-used and combined with the results of other more invasive modernization techniques such as re-architecting. Using SOA integration, an organization can begin to make use of SOA concepts, including the orchestration of services into business processes, leaving the legacy application intact. Of course, the appropriate interfaces into the legacy application must exist and the code behind these interfaces must perform useful functions in a manner that can be packaged as services. SOA readiness assessment involves analysis of service granularity, exception handling, transaction integrity and reliability requirements, considerations of response time, message sizes, and scalability, issues of end-to-end messaging security, and requirements for services orchestration and SLA management. Following an assessment, any issues discovered need to be rectified before exposing components as services, and appropriate run-time and lifecycle governance policies created and implemented. It is important to note that there are three tiers where integration can be done: Data, Screen, and Code. So, each of the tiers, based upon the state and structure of the code, can be extended with this technique. As mentioned before, this is often the first step in modernization. In this example, we can see that the legacy systems still stay on the legacy platform. Here, we isolate and expose this information as a business service using legacy adapters. The table below lists important considerations in SOA integration and enablement projects. Criteria for identifying well defined services Represent a core enterprise function re-usable by many client applications Present a coarse-grained interface Single interaction vs. multi-screen flows UI, business logic, data access layers Exception handling-returning results without branching to another screen Discovering "Services" beyond screen flows Conversational vs. sync/async calls COMMAREA transactions (re-factored to use reasonable message size) Security policies and their enforcement RACF vs. LDAP-based or SSO mechanism End-to-end messaging security and Authentication, Authorization, Audition   Services integration and orchestration Wrapping and proxying via middle-tier gate-way vs. mainframe-based services Who's responsible for input validation? Orchestrating "composite" MF services Supporting bidirectional integration Quality of Service (QoS) requirements Response time, throughput, scalability End-to-end monitoring and SLA management Transaction integrity and global transaction coordination End-to-end monitoring and tracing Services lifecycle governance Ownership of service interfaces and change control process Service discovery (repository, tools) Orchestration, extension BPM integration

Now that you understand the process behind forms authentication, we need to add it to our application. The process will be slightly different because we already have a database to use, but without the ASP.NET membership schema. We'll add that to the database and then create some user accounts and membership roles to handle the security for our application. We'll also secure some of our content and add a menu to our Master Page to navigate between the pages of our Content Management System. Preparing an existing SQL database As we have an existing database, we can't create a new database for our membership and authentication system. Well, actually we could, but using a second database is problematic when we upload the application to a host because many web hosting companies allow only a single database under the hosting plan. Besides, we can easily add the membership schema the same way we did earlier in the article with our empty database, using aspnet_regsql.exe. Previously we used the wizard, this time we'll use the command line. If you take a look at the database in SQL Server Management Studio Express now, before we execute the command to add the schemas, you should see the few tables that were already created, as shown below: The aspnet_regsql.exe tool Using the command line, the executable is simple, as long as you know the command line arguments. The syntax and command arguments for aspnet_regsql.exe are available online at http://msdn.microsoft.com/en-us/library/x28wfk74.aspx. The following table shows the arguments we will use: Argument Description What we use -S The server name SQLEXPRESS -U The database username sa -P The database password SimpleCMS -d The database name SimpleCMS_Database -A The schema functions to install All functions   Our command line will look like this (all one line): aspnet_regsql.exe -S .SQLEXPRESS -U sa -P SimpleCMS -d SimpleCMS_Database -A all To run the command line, go to Start | Run and enter cmd in the Run dialog box. Press Enter and you will be at a command prompt. Type cd C:WINDOWSMicrosoft.NETFrameworkv2.0.50727 and press Enter again, and you will be in the correct folder to find aspnet_regsql.exe. Note that you may need to change the path if your ASP.NET framework files are in a different location. Type the command line above and press Enter, and you should see that the command completed successfully, with a dialog similar to that below: Now that we have executed the aspnet_regsql.exe command line, if you look at the database tables in SQL Server Management Studio Express, you should see the added table for the users, membership, and roles we will use in our application. User accounts Earlier in the article, we created a single user account for accessing protected content. In a real-world environment, we would normally have many user accounts, way too many to add each account to each page we wanted to protect. Fortunately, the ASP.NET framework provides us with membership roles that we can place user accounts in, allowing us to define our access by role, not by user account. But first, we need some user accounts. Let's start by creating three accounts in our application  - User1, User2, and Administrator. Open the SimpleCMS web site in Visual Web Developer 2008 Express. Use the downloadable code provided for Chapter 4 of this book, it has the web.config file modified similar to what we did when we walked through the forms authentication demo earlier in the chapter. Open the Web Site Administration Tool by clicking on Website and then ASP.NET Configuration. If you click on the Security tab, you will see that we have no users configured for this application.  As you did earlier in the article, click on Create User and create the three users with user names of User1, User2, and Administrator. Use Password! as the password for each, and provide a valid email address for each (they can have the same email for testing). Also, provide a question and answer such as Favorite Color? and Blue. You can use the same question and answer for all three accounts if you wish. Each user entry should look something like the following: If you return to the Security tab, you will notice that we have three user accounts, but no roles for those accounts. Let's add them next. Membership roles ASP.NET membership roles provide the ability to group many individual accounts into a single role to provide access to a resource such as a page or application. Changing access for an individual user then becomes a simple task of assigning them to or removing them from the appropriate role. A single user account can belong to multiple roles to provide extremely granular access to the application resources if your security demands are extensive. To add roles to our application, we first need to enable roles. On the Security tab of the Web Site Administration Tool, under Roles, you should see a link to enable roles. Enabling roles consists of simply adding the following line to the web.config file in the system.web section: <roleManager enabled="true" /> Similar to the membership provider we created earlier, roles require a role provider. We need to add this provider to the role manager, so edit the web.config roleManager section to read: <roleManager enabled="true"><providers><clear/><add name="AspNetSqlRoleProvider"connectionStringName="SimpleCMS_DatabaseConnectionString"applicationName="/"type="System.Web.Security.SqlRoleProvider, System.Web,Version=2.0.0.0,Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" /></providers></roleManager> This adds an AspNetSqlRoleProvider that uses our connection string to the SimpleCMS database. At this point we have no roles defined, so let's create a few. Open the Web Site Administration Tool. If it's already open, you may need to close and reopen it because we modified the web.config file to add the role provider. Now, open the Security tab. In the Roles section, click on Create or manage roles. Let's create an administration role first. We'll need it to secure areas to just administrative access. Simply enter Administrator, click on Add Role, and you'll see the new role in the list. Add roles for Author, Editor, and Registered User in the same manner. The roles list should look something like the following figure when you finish: Adding users to roles Once we have users and roles created, we need to assign users to roles. To do this, use the Security tab of the Web Site Administration Tool, under the Users section, to manage users.  You'll see a list of user accounts, in our case all three of them, along with the ability to edit the user, delete the user, and edit the user's roles. Click on Edit roles next to the Administrator user and you'll see a checkbox list of user roles this account can be added to. Any roles currently assigned to the user will be checked. As there are currently none, check the Administrator role, and the Administrator user will be immediately added to the Administrator role, as shown below: If you were to look at the database tables that hold the user accounts and roles, you would see something like this for the users: Similarly, the roles would look like this: You'll note that both the users and the roles contain an ApplicationID that defines what application these users and roles belong to, and that each user or role is identified by a UserID or RoleID. These are automatically created by the ASP.NET membership framework and are globally unique identifiers (GUIDs), which ensure that the specific user or role is unique across all possible applications and uses of this specific database store. You would also find in the database a table that identifies users in roles, looking something like this: You'll notice that this is a joining table, used in a database when there is a many-to-many relationship. Many users can belong to a role and a user can belong to many roles, thus the use of this table. You'll also notice that the database table uses the UserID and RoleID, making it very hard to simply look at this table directly to find what users are assigned to what roles.  Fortunately, with the ASP.NET framework, you're isolated from having to work directly with the database, as well as relieved from having to create it and the code needed to access it.

Recipe 87: Creating an issue Page Bookmark IngredientsWeb Browser The issue queue is the central place of progress for Drupal modules. It serves as a place to find answers, patches, new ideas, and work on common concerns. Issues are referenced by number. On occasion, a web page will contain an issue queue number in text form rather than a full link to the issue. This recipe, once set up, simply saves the trouble of having to type drupal.org/node/ into the browser address bar. Just select the number and the bookmark will take you there. In Firefox add a new Bookmark onto the toolbar. Select Bookmarks | Organize Bookmarks | Bookmarks Toolbar | Organize | New Bookmark Set the Name to Drupal Issue and set the Location to the following: javascript:inum=escape(getSelection());location.href='http://www.drupal.org/node/'+inum. Visit a web page that contains an issue number and select the issue number text. For instance, try http://cvs.drupal.org/viewvc.py/drupal/contributions/modules/views/modules/views_taxonomy.inc. (Be sure to exclude the surrounding space and pound sign when selecting the number.) Click the Drupal Issue button in the bookmark toolbar. Recipe notes This bookmark approach may be replicated to visit a URL containing any selectable text. For instance, below is a variation to display all of your delicious bookmarks tagged with the selected text. (Delicious.com—also found at http://del.icio.us, is a wonderful online bookmark service.) Replace <ACCOUNTNAME> with your delicious.com account. Name: DeliciousLocation: javascript_tag=escape(getSelection());location.href='http://delicious.com/<ACCOUNTNAME>/'+tag Recipe 88: Searching the Views issue queue IngredientsWeb Browser In this recipe we look closely at how to search the Views issue queue. The lessons apply to all other Drupal projects as well. It is always a good idea to search the issue queue for related content before posting. Log on to drupal.org (if you are not already a member of the Drupal site, become a member). Basic Search Visit http://drupal.org/project/issues/views. At this main issue queue page you may search for text or filter by Status, Priority, Category, Version, or Component. These options are discussed in further detail below. You may also sort the table of issues by clicking on the table header. By default, the table is sorted by date. Advanced Search Go to the Views issue queue Advanced Search page. Visit the URL directly, at http://drupal.org/project/issues/search/views. From the project page (drupal.org/project/views), find the Issues block on the left, and click on the Advanced Search link. From the issue queue (drupal.org/project/issues/views), the Advanced Search Link appears under the title. There are a variety of routes to get there: Get to know the search options. Although there are ten form elements to choose, most users will routinely use just a few, leaving the other options blank. Search For (Routinely used): Enter search text. Use quotation marks to create a phrase. Assigned: This field is generally used by issue maintainers. Submitted by: This is most often used to find your own issues, though it could be used to see what other Drupal users are posting as well. Participant: This is also used to find your own posts. Note that Submitted by finds only the initial post by a user in the issue queue. Participant additionally includes responses to initial posts. Status: Leave blank to get all statuses. You may also select multiple options. For instance, you could select all issues designated as needs work, needs review, and reviewed & tested by the community. Scroll down the list and note Status filters such as closed issues, duplicates, issues that the maintainer won't fix, and features noted as by design. These are the statuses that are excluded if you select -Open Issues-. Priority: Leave blank to get all priorities. Category: Leave blank to get all categories. Version (Routinely used): A relative new option, 5.x issues saves you the trouble of having to Shift+click on each Drupal 5 release name. Component: The views module issue queue offers more component options than most modules. As a result, users may not always be familiar with properly assigning a component when they create an issue. A search of exposed filters components, for instance, may not find as many results as a text search of "exposed filters." Component can occasionally be a helpful selection, but is most often left blank. Issue Tags: These may be a challenge to search since few people add tag issues. This may become a more popular option in the future. Recipe notes Search ideas: Find all your posts by filling in your drupal.org user name under participant. Find patches by selecting all of the four patch statuses. Find all documentation issues connected to Views for Drupal 5.x. Go to another issue queue http://drupal.org/project/issues/search/<MODULENAME> and search for the word Views. From the module issue pages http://drupal.org/project/issues/<MODULENAME> you may also review module Statistics, and Subscribe to issues. Subscribe to your Own Issues (the default), None, or All Issues. I don't recommend the latter for the Views module as you will be setting yourself up for a deluge of email. Search across all projects at http://drupal.org/search/issues. Recipe 89: Posting an issue Posting a New issue If you are new to posting Drupal issues, consider just reading the issue queue for at least several days before posting. This will help you to get a sense of the culture of issue queue interaction. If you don't already have an account on drupal.org get one. Look for the User login block on the home page, and click on Create new account. Complete the steps to login. Search the issue queue before you post! (Recipe 88). If your topic already has an associated active issue, reply rather than posting a new issue.Also, before posting to the issue queue in a panic read the Drupal Troubleshooting FAQ http://drupal.org/Troubleshooting-FAQ. For instance, standard fare is to increase memory in the face of the White Screen of Death (WSOD) or to disable buggy modules by setting the status = 0 in the system table. Be sure to know which version of the module you're using. Is it the dev (development) version? Is it the latest recommended release? The version number can generally be found at http://YOURSITE.com/admin/build/modules. To start a new issue, go to http://drupal.org/project/issues/<MODULENAME> and click on Create a new issue. This directs the browser to: http://drupal.org/node/add/project-issue/<MODULENAME>. For the Views module, the link at http://drupal.org/node/add/project-issue/views offers guidance (in bold!) for posting. Read it! Much of it applies to Views 2 but it contains useful information for Views 1 users as well. Required fields for a new issue include Version, Component, Category, Title, and Description. Be thoughtful with these details. For instance, do not title your issue HELP??!! A much more useful description would be something like Missing taxonomy terms in filters. Priority should generally be left as normal. Critical is reserved for occasions then the module simply does not work. Responding to an existing issue You may also respond to an existing issue by selecting the Add New Comment link or one of the Reply links on an individual issue page. Another option is just to scroll down to the bottom of the issue page, and begin entering a response. Unlike some forum tools, in which replies are indented, all new comments are given a new comment number, and added to the bottom of the comments. When responding to an issue you may take a variety of actions: Change the Issue Title. In general, don't change this unless you have a very good reason (for instance, if the original title is misleading, or spelled wrong). Some people are used to forums where a response can have a different name as the original post. In the issue queue, changing the name when responding to an issue actually changes the name of the issue. This is generally best left untouched. Change the Project. A question that someone asks in the Views issue queue may be more appropriately managed in the issue queue for a different module. This is a rare change generally left to the maintainer of one of the two modules who will know in which issue queue a discussion belongs. Change the Version number, Component, Category, or Priority. These changes are rare (correcting the version number is probably the most common). When changes are made, they are noted in the post as shown below: Change Assign. Do not assign someone other than yourself to an issue. Assign yourself if you are sure that you will soon fix the issue. It is quite common to leave this as Unassigned. Change the Status. For instance: Mark an issue as a duplicate (always provide a pointer to the issue it duplicates). Note that a patch is reviewed and tested by the community. Post a question, patch, answer, or idea related to the issue in the Comment section. Open the Input format fieldset below the comment field to see what markup is available. Note the <code> tag, for instance (and remember to close it with a </code> tag). Attach a file. Recipe notes Remember that respondents and maintainers are volunteers. They are generally very busy people who want to help, but they do not have time to do free consulting. See the following pages for spirited discussions about issue queue etiquette: http://acko.net/blog/whats-wrong-with-drupal http://paul.leafish.co.uk/articles/drupal/on_subscribing_to_module_portingupdating_issues One discussion theme is the merit of simply sending the word subscribe to the issue queue. People sometimes do this so that they can track an issue—receiving an email alert each time something new is posted. On drupal.org it is possible to subscribe to a node only if you leave a comment, but most people prefer comments with substance. You may create functionality similar to the Drupal issue queue on your own site by installing the project, project_issue, and comment_upload modules.

What is WCF? WCF is the acronym for Windows Communication Foundation. It is Microsoft's latest technology that enables applications in a distributed environment to communicate with each other. WCF is Microsoft's unified programming model for building service-oriented applications. It enables developers to build secure, reliable, transacted solutions that integrate across platforms and interoperate with existing investments. WCF is built on the Microsoft .NET Framework and simplifies the development of connected systems. It unifies a broad array of distributed systems capabilities in a composable, extensible architecture that supports multiple transports, messaging patterns, encodings, network topologies, and hosting models. It is the next version of several existing products—ASP.NET's web methods (ASMX) and Microsoft Web Services Enhancements (WSE) for Microsoft .NET, .NET Remoting, Enterprise Services, and System.Messaging. The purpose of WCF is to provide a single programming model that can be used to create services on the .NET platform for organizations. Why is WCF used for SOA? As we have seen in the previous section, WCF is an umbrella technology that covers ASMX web services, .NET remoting, WSE, Enterprise Service, and System.Messaging. It is designed to offer a manageable approach to distributed computing, broad interoperability, and direct support for service orientation. WCF supports many styles of distributed application development by providing a layered architecture. At its base, the WCF channel architecture provides asynchronous, untyped message-passing primitives. Built on top of this base are protocol facilities for secure, reliable, transacted data exchange and a broad choice of transport and encoding options. Let us take an example to see why WCF is a good approach for SOA. Suppose a company is designing a service to get loan information. This service could be used by the internal call center application, an Internet web application, and a third-party Java J2EE application such as a banking system. For interactions with the call center client application, performance is important. For communication with the J2EE-based application however, interoperability becomes the highest goal. The security requirements are also quite different between the local Windows-based application, and the J2EE-based application running on another operating system. Even transactional requirements might vary, with only the internal application being allowed to make transactional requests. With these complex requirements, it is not easy to build the desired service with any single existing technology. For example, the ASMX technology may serve well for the interoperability, but its performance may not be ideal. The .NET remoting will be a good choice from the performance perspective, but it is not good at interoperability. Enterprise Services could be used for managing object lifetimes and defining distributed transactions, but Enterprise Services supports only a limited set of communication options. Now with WCF, it is much easier to implement this service. As WCF has unified a broad array of distributed systems capabilities, the get loan service can be built with WCF for all of its application-to-application communication. The following shows how WCF addresses each of these requirements: Because WCF can communicate using web service standards, interoperability with other platforms that also support SOAP, such as the leading J2EE-based application servers, is straightforward. You can also configure and extend WCF to communicate with web services using messages not based on SOAP, for example, simple XML formats such as RSS. Performance is of paramount concern for most businesses. WCF was developed with the goal of being one of the fastest distributed application platforms developed by Microsoft. To allow for optimal performance when both parties in a communication are built on WCF, the wire encoding used in this case is an optimized binary version of an XML Information Set. Using this option makes sense for communication with the call center client application, because it is also built on WCF, and performance is an important concern. Managing object lifetimes, defining distributed transactions, and other aspects of Enterprise Services, are now provided by WCF. They are available to any WCF-based application, which means that the get loan service can use them with any of the other applications that it communicates with. Because it supports a large set of the WS-* specifications, WCF helps to provide reliability, security, and transactions when communicating with any platform that supports these specifications. The WCF option for queued messaging, built on Message Queuing, allows applications to use persistent queuing without using another set of application programming interfaces. The result of this unification is greater functionality, and significantly reduced complexity. WCF architecture The following diagram illustrates the major layers of the Windows Communication Foundation (WCF) architecture. This diagram is taken from the Microsoft web site (http://msdn.microsoft.com/en-us/library/ms733128.aspx): The Contracts layer defines various aspects of the message system. For example, the Data Contract describes every parameter that makes up every message that a service can create or consume. The Service runtime layer contains the behaviors that occur only during the actual operation of the service, that is, the runtime behaviors of the service. The Messaging layer is composed of channels. A channel is a component that processes a message in some way, for example, authenticating a message. In its final form, a service is a program. Like other programs, a service must be run in an executable format. This is known as the hosting application. In the next section, we will explain these concepts in detail. Basic WCF concepts—WCF ABCs There are many terms and concepts around WCF, such as address, binding, contract, endpoint, behavior, hosting, and channels. Understanding these terms is very helpful when using WCF. Address The WCF Address is a specific location for a service. It is the specific place to which a message will be sent. All WCF services are deployed at a specific address, listening at that address for incoming requests. A WCF Address is normally specified as a URI, with the first part specifying the transport mechanism, and the hierarchical part specifying the unique location of the service. For example, http://www.myweb.com/myWCFServices/SampleService can be an address for a WCF service. This WCF service uses HTTP as its transport protocol, and it is located on the server www.myweb.com, with a unique service path of myWCFServices/SampleService. The following diagram illustrates the three parts of a WCF service address. Binding Bindings are used to specify the transport, encoding, and protocol details required for clients and services to communicate with each other. Bindings are what WCF uses to generate the underlying wire representation of the endpoint. So, most of the details of the binding must be agreed upon by the parties that are communicating. The easiest way to achieve this is for clients of a service to use the same binding that the service uses. A binding is made up of a collection of binding elements. Each element describes some aspect of how the service communicates with clients. A binding must include at least one transport binding element, at least one message encoding binding element (which can be provided by the transport binding element by default), and any number of other protocol binding elements. The process that builds a runtime out of this description allows each binding element to contribute code to that runtime. WCF provides bindings that contain common selections of binding elements. These can either be used with their default settings, or the default values can be modified according to user requirements. These system-provided bindings have properties that allow direct control over the binding elements and their settings. The following are some examples of the system-provided bindings: BasicHttpBinding, WSHttpBinding, WSDualHttpBinding, WSFederationHttpBinding, NetTcpBinding, NetNamedPipeBinding, NetMsmqBinding, NetPeerTcpBinding, and MsmqIntegrationBinding. Each one of these built-in bindings has predefined required elements for a common task, and is ready to be used in your project. For instance, the BasicHttpBinding uses HTTP as the transport for sending SOAP 1.1 messages, and it has attributes and elements such as receiveTimeout, sendTimeout, maxMessageSize, and maxBufferSize. You can accept the default settings of its attributes and elements, or overwrite them as needed. Contract A WCF contract is a set of specifications that define the interfaces of a WCF service. A WCF service communicates with other applications according to its contracts. There are several types of WCF contracts, such as Service Contract, Operation Contract, Data Contract, Message Contract, and Fault Contract. Service contract A service contract is the interface of the WCF service. Basically, it tells others what the service can do. It may include service-level settings, such as the name of the service, the namespace of the service, and the corresponding callback contracts of the service. Inside the interface, it can define a bunch of methods, or service operations for specific tasks. Normally, a WCF service has at least one service contract. Operation contract An operation contract is defined within a service contract. It defines the parameters and return type of an operation. An operation can take data of a primitive (native) data type, such as an integer as a parameter, or it can take a message, which should be defined as a message contract type. Just as a service contract is an interface, an operation contract is a definition of an operation. It has to be implemented in order that the service functions as a WCF service. An operation contract also defines operation-level settings, such as the transaction flow of the operation, the directions of the operation (one-way, two-way, or both ways), and fault contract of the operation. The following is an example of an operation contract: [WCF::FaultContract(typeof(MyWCF.EasyNorthwind.FaultContracts.ProductFault))]MyWCF.EasyNorthwind.MessageContracts.GetProductResponseGetProduct(MyWCF.EasyNorthwind.MessageContracts.GetProductRequest request); In this example, the operation contract's name is GetProduct, and it takes one input parameter, which is of type GetProductRequest (a message contract) and has one return value, which is of type GetProductResponse (another message contract). It may return a fault message, which is of type ProductFault (a fault contract), to the client applications. We will cover message contract and fault contract in the following sections. Message contract If an operation contract needs to pass a message as a parameter or return a message, the type of these messages will be defined as message contracts. A message contract defines the elements of the message, as well as any message-related settings, such as the level of message security, and also whether an element should go to the header or to the body. The following is a message contract example: namespace MyWCF.EasyNorthwind.MessageContracts{ /// <summary> /// Service Contract Class - GetProductResponse /// </summary> [WCF::MessageContract(IsWrapped = false)] public partial class GetProductResponse { private MyWCF.EasyNorthwind.DataContracts.Product product; [WCF::MessageBodyMember(Name = "Product")] public MyWCF.EasyNorthwind.DataContracts.Product Product { get { return product; } set { product = value; } } }} In this example, the namespace of the message contract is MyWCF.EasyNorthwind.MessageContracts, and the message contract's name is GetProductResponse. This message contract has one member, which is of type Product. Data contract Data contracts are data types of the WCF service. All data types used by the WCF service must be described in metadata to enable other applications to interoperate with the service. A data contract can be used by an operation contract as a parameter or return type, or it can be used by a message contract to define elements. If a WCF service uses only primitive (native) data types, it is not necessary to define any data contract. The following is an of example data contract: namespace MyWCF.EasyNorthwind.DataContracts{ /// <summary> /// Data Contract Class - Product /// </summary> [WcfSerialization::DataContract(Namespace = "http://MyCompany.com/ ProductService/EasyWCF/2008/05", Name = "Product")] public partial class Product { private int productID; private string productName; [WcfSerialization::DataMember(Name = "ProductID", IsRequired = false, Order = 0)] public int ProductID { get { return productID; } set { productID = value; } } [WcfSerialization::DataMember(Name = "ProductName", IsRequired = false, Order = 1)] public string ProductName { get { return productName; } set { productName = value; } } }} In this example, the namespace of the data contract is MyWCF.EasyNorthwind.DataContracts, the name of the data contract is Product, and this data contract has two members (ProductID and ProductName).   Fault contract In any WCF service operation contract, if an error can be returned to the caller, the caller should be warned of that error. These error types are defined as fault contracts. An operation can have zero or more fault contracts associated with it. The following is a fault contract example: namespace MyWCF.EasyNorthwind.FaultContracts{ /// <summary> /// Data Contract Class - ProductFault /// </summary> [WcfSerialization::DataContract(Namespace = "http://MyCompany.com/ ProductService/EasyWCF/2008/05", Name = "ProductFault")] public partial class ProductFault { private string faultMessage; [WcfSerialization::DataMember(Name = "FaultMessage", IsRequired = false, Order = 0)] public string FaultMessage { get { return faultMessage; } set { faultMessage = value; } } }} In this example, the namespace of the fault contract is MyWCF.EasyNorthwind.FaultContracts, the name of the fault contract is ProductFault, and the fault contract has only one member (FaultMessage). Endpoint Messages are sent between endpoints. Endpoints are places where messages are sent or received (or both), and they define all of the information required for the message exchange. A service exposes one or more application endpoints (as well as zero or more infrastructure endpoints). A service can expose this information as the metadata that clients can process to generate appropriate WCF clients and communication stacks. When needed, the client generates an endpoint that is compatible with one of the service's endpoints. A WCF service endpoint has an address, a binding, and a service contract(WCF ABC). The endpoint's address is a network address where the endpoint resides. It describes, in a standard-based way, where messages should be sent. Each endpoint normally has one unique address, but sometimes two or more endpoints can share the same address. The endpoint's binding specifies how the endpoint communicates with the world, including things such as transport protocol (TCP, HTTP), encoding (text, binary), and security requirements (SSL, SOAP message security). The endpoint's contract specifies what the endpoint communicates, and is essentially a collection of messages organized in the operations that have basic Message Exchange Patterns (MEPs) such as one-way, duplex, or request/reply. The following diagram shows the components of a WCF service endpoint. Behavior A WCF behavior is a type, or settings to extend the functionality of the original type. There are many types of behaviors in WCF, such as service behavior, binding behavior, contract behavior, security behavior and channel behavior. For example, a new service behavior can be defined to specify the transaction timeout of the service, the maximum concurrent instances of the service, and whether the service publishes metadata. Behaviors are configured in the WCF service configuration file. Hosting A WCF service is a component that can be called by other applications. It must be hosted in an environment in order to be discovered and used by others. The WCF host is an application that controls the lifetime of the service. With .NET 3.0 and beyond, there are several ways to host the service. Self hosting A WCF service can be self-hosted, which means that the service runs as a standalone application and controls its own lifetime. This is the most flexible and easiest way of hosting a WCF service, but its availability and features are limited. Windows services hosting A WCF service can also be hosted as a Windows service. A Windows service is a process managed by the operating system and it is automatically started when Windows is started (if it is configured to do so). However, it lacks some critical features (such as versioning) for WCF services. IIS hosting A better way of hosting a WCF service is to use IIS. This is the traditional way of hosting a web service. IIS, by nature, has many useful features, such as process recycling, idle shutdown, process health monitoring, message-based activation, high availability, easy manageability, versioning, and deployment scenarios. All of these features are required for enterprise-level WCF services. Windows Activation Services hosting The IIS hosting method, however, comes with several limitations in the service-orientation world; the dependency on HTTP is the main culprit. With IIS hosting, many of WCF's flexible options can't be utilized. This is the reason why Microsoft specifically developed a new method, called Windows Activation Services, to host WCF services. Windows Process Activation Service (WAS) is the new process activation mechanism for Windows Server 2008 that is also available on Windows Vista. It retains the familiar IIS 6.0 process model (application pools and message-based process activation) and hosting features (such as rapid failure protection, health monitoring, and recycling), but it removes the dependency on HTTP from the activation architecture. IIS 7.0 uses WAS to accomplish message-based activation over HTTP. Additional WCF components also plug into WAS to provide message-based activation over the other protocols that WCF supports, such as TCP, MSMQ, and named pipes. This allows applications that use the non-HTTP communication protocols to use the IIS features such as process recycling, rapid fail protection, and the common configuration systems that were only available to HTTP-based applications. This hosting option requires that WAS be properly configured, but it does not require you to write any hosting code as part of the application. [Microsoft MSN, Hosting Services, retrieved on 3/6/2008 from http://msdn2.microsoft.com/en-us/library/ms730158.aspx] Channels As we have seen in the previous sections, a WCF service has to be hosted in an application on the server side. On the client side, the client applications have to specify the bindings to connect to the WCF services. The binding elements are interfaces, and they have to be implemented in concrete classes. The concrete implementation of a binding element is called a channel. The binding represents the configuration, and the channel is the implementation associated with that configuration. Therefore, there is a channel associated with each binding element. Channels stack on top of one another to create the concrete implementation of the binding—the channel stack. The WCF channel stack is a layered communication stack with one or more channels that process messages. At the bottom of the stack is a transport channel that is responsible for adapting the channel stack to the underlying transport (for example, TCP, HTTP, SMTP and other types of transport). Channels provide a low-level programming model for sending and receiving messages. This programming model relies on several interfaces and other types collectively known as the WCF channel model. The following diagram shows a simple channel stack: Metadata The metadata of a service describes the characteristics of the service that an external entity needs to understand in order to communicate with the service. Metadata can be consumed by the ServiceModel Metadata Utility Tool (Svcutil.exe) to generate a WCF client and the accompanying configuration that a client application can use to interact with the service. The metadata exposed by the service includes XML schema documents, which define the data contract of the service, and WSDL documents, which describe the methods of the service. Though WCF services will always have metadata, it is possible to hide the metadata from outsiders. If you do so, you have to pass the metadata to the client side by other means. This practice is not common, but it gives your services an extra layer of security. When enabled via the configuration settings through metadata behavior, metadata for the service can be retrieved by inspecting the service and its endpoints. The following configuration setting in a WCF service configuration file will enable the metadata publishing for HTTP transport protocol: <serviceMetadata httpGetEnabled="true" />

If our Lighttpd runs on a multi-processor machine, it can take advantage of that by spawning multiple versions of itself. Also, most Lighttpd installations will not have a machine to themselves; therefore, we should not only measure the speed but also its resource usage. Optimizing Compilers: gcc with the usual settings (-O2) already does quite a good job of creating a fast Lighttpd executable. However, -O3 may nudge the speed up a tiny little bit (or slow it down, depending on our system) at the cost of a bigger executable system. If there are optimizing compilers for our platform (for example, Intel and Sun Microsystems each have compilers that optimize for their CPUs), they might even give another tiny speed boost. If we do not want to invest money in commercial compilers, but maximize on what gcc has to offer, we can use Acovea, which is an open source project that employs genetic algorithms and trial-and-error to find the best individual settings for gcc on our platform. Get it from http://www.coyotegulch.com/products/acovea/ Finally, optimization should stop where security (or, to a lesser extent, maintainability) is compromised. A slower web server that does what we want is way better than a fast web server obeying the commands of a script kiddie. Before we optimize away blindly, we better have a way to measure the "speed". A useful measure most administrators will agree with is "served requests per second". http_load is a tool to measure the requests per second. We can get it from http://www.acme.com/software/http_load/. http_load is very simple. Give it a site to request, and it will flood the site with requests, measuring how many are served in a given amount of time. This allows a very simplistic approach to optimizing Lighttpd: Tweak some settings, run http_load with a sufficient realistic scenario, and see if our Lighttpd handles more or less requests than before. We do not yet know where to spend time optimizing. For this, we need to make use of timing log instrumentation that has been included with Lighttpd 1.5.0 or even use a profiler to see where the most time is spent. However, there are some "big knobs" to turn that can increase performance, where http_load will help us find a good setting. Installing http_load http_load can be downloaded as a source .tar file (which was named .tar.gz for me, though it is not gzipped). The version as of this writing is 12Mar2006. Unpack it to /usr/src (or another path by changing the /usr/src) with: $ cd /usr/src && tar xf /path/to/http_load-12Mar2006.tar.gz$ cd http_load-12Mar2006 We can optionally add SSL support. We may skip this if we do not need it. To add SSL support we need to find out where the SSL libs and includes are. I assume they are in /usr/lib and /usr/include, respectively, but they may or may not be the same on your system. Additionally, there is a "SSL tree" directory that is usually in /usr/ssl or /usr/local/ssl and contains certificates, revocation lists, and so on. Open the Makefile with a text editor and look at line 11 to 14, which reads: #SSL_TREE = /usr/local/ssl#SSL_DEFS = -DUSE_SSL#SSL_INC = -I$(SSL_TREE)/include#SSL_LIBS = -L$(SSL_TREE)/lib -lssl -lcrypto Change them to the following (assuming the given directories are correct): SSL_TREE = /usr/sslSSL_DEFS = -DUSE_SSLSSL_INC = -I/usr/includeSSL_LIBS = -L/usr/lib -lssl -lcrypto Now compile and install http_loadwith the following command: $ make all install Now we're all set to load-test our Lighttpd. Running http_load tests We just need a URL file, which contains URLs that lead to the pages our Lighttpd serves. http_load will then fetch these pages at random as long as, or as often as we ask it to. For example, we may have a front page with links to different articles. We can just start putting a link to our front page into the URL file, which we will name urls to get started; for example, http://localhost/index.html. Note that the file just contains URLs, nothing less, nothing more (for example, http_load does not support blank lines). Now we can make our first test run: $ http_load -parallel 10 -seconds 60 urls This will run for one minute and try to open 10 connections per second. Let's see if our Lighttpd keeps up: 343 fetches, 10 max parallel, 26814 bytes, in 60 seconds78.1749 mean bytes/connection5.71667 fetches/sec, 446.9 bytes/secmsecs/connect: 290.847 mean, 9094 max,15 minmsecs/first-response: 181.902 mean, 9016 max, 15 minHTTP response codes: code 200 - 327   As we can see, it does. http_load needs one of the two start conditions and one of the two stop conditions plus a URL file to run. We can create the URL file manually or crawl our document root(s) with the following python script called crawl.py: #!/usr/bin/python#run from document root, pipe into URLs file. For example:# /path/to/docroot$ crawl.py > urlsimport os, re, syshostname = "http://localhost/"for (root, dirs, files) in os.walk("."): for name in files: filepath = os.path.join(root, name) print re.sub("./", hostname, filepath)   You can download the crawl.oy file from http://www.packtpub.com/files/code/2103_Code.zip. Capture the output into a file to use as URL file. For example, start the script from within our document root with: $ python crawl.py > urls This will give us a urls file, which will make http_load try to get all files (given that we have specified enough requests). Then we can start http_load as discussed in the preceding example. http_load takes the following options:  

Microsoft Office 2003 add-ins For Microsoft Windows users, a natural way of working with the files is by using the Microsoft Office tools. It would be a tedious job for Content Managers to have to search and locate the documents using an Alfresco web client, copy them onto their local desktop, edit them, upload them to Alfresco, and secure them. How about having all of the features mentioned above in your choice of editor itself? Alfresco provides Office add-ins for MS Word 2003, MS Excel 2003, and MS PowerPoint 2003, to allow them to manage the content directly from those tools. This improves the productivity of Content Managers. Support for Microsoft Office 2007 Although the Alfresco add-ins were developed for Microsoft Office 2003, they are also compatible with Microsoft Office 2007. If you are using Microsoft Office 2007 on Windows Vista, then the add-in is not effective, as it provides read-only access to the repository. Unfortunately, this is a known problem with Vista, as Microsoft has rewritten the WebDAV parts of Vista. You may consider the workarounds that are provided at the following URL: http://blogs.msdn.com/sharepoint/archive/2007/10/19/known-issue-office-2007-on-windows-vista-prompts-for-user-credentials-when-opening-documents-in-a-sharepoint-2007-site.aspx Installation Download the Alfresco office add-ins (ZIP file) from the source forge web site, by visiting the following URL: http://sourceforge.net/project/showfiles.php?group_id=143373&package_id=237030 An individual installer (for Microsoft Word, Excel, and Power Point), as well as a combined installer, is available for download. Select an appropriate add-into download. Unzip the ZIP file and run the Setup.exe file contained within it. The set-up program will download the components that are needed, from the Microsoft web site. Once the set-up is complete, you can open the Office tool and use the add-in. For example, for MS Word 2003, you will notice a new button named Alfresco. For MS Word 2007, you will notice the add-in, as shown in the following screenshot: Configuration Click on the Alfresco button to open the add-in window. You need to configure the add-in, by clicking on the link provided at the bottom of the add-in window. Provide the URL details for the web client, WebDAV, and CIFS, as shown in the upcoming screenshot. No matter how you access the repository, you will still have to go through Alfresco's security rules. Provide the Userid and password for the purpose of authentication. The access to the Alfresco repository will be based on the authorization of the user. Click on the Save Settings button to go the main screen. If you have more than one Alfresco server to connect to, then you might have to manually change the settings as needed. Currently, there is no facility for storing the settings for more than one Alfresco server. Features of MS Word add-in The Alfresco add-in allows you to carry out the following activities directly from Microsoft Word. Refer to the following screenshot for more details: My Alfresco: Displays the My Alfresco dashlets Browse Spaces: Browses the entire repository for spaces and files. Search: Searches the repository for keywords. View Details: Views the details of the selected document. Workflow: Starts workflow for the active document. Tags: Allows you to add tags to the document. Transform to PDF: Transforms the selected MS Word document into PDF. Insert into Word: Inserts the selected document into Microsoft Word for editing. Save to Alfresco: Saves the current document to the current space. If the document has not been given a filename yet, then a pop-up panel will prompt you for one. Editing a file in Word To edit a file in Microsoft Word, double-click on the file name. The file is opened directly for editing. The MS Word file is locked for others, while it is being edited by you, as shown in the upcoming screenshot. You can perform all of the Alfresco repository activities, such as adding new tags and initiating a workflow approval process. Saving the file in Microsoft Word will directly save it in the Alfresco repository. If auto version is enabled, then it will be versioned automatically. When you close the file in MS Word, or exit from MS Word, the file will be unlocked in the repository. Recovering deleted content When you delete an item (either content or space) in Alfresco, the item is not deleted from the server, but is moved to a temporary store called Archive Space Store. This gives you a chance to recover items that were deleted. Deleted items will be kept in the temporary store forever, until you decide to either recover or purge them. These features are available to administrators through the Manage Deleted Items action. To test these features, log in as an administrator, create a couple of dummy files in any space, and then delete them. Click on the User Profile Icon  option, located above the menu item, and then click on the Manage Deleted Items button. The Manage Deleted Items pane appears, as shown in the following screenshot: You can list all of the deleted content by clicking on the Show All button, as highlighted in the preceding screenshot. You can also search for deleted items by name, by content, by date, or by the person who deleted it, by using the search options provided. Select the item that you previously deleted, and then click on the Recover Listed Items icon, as shown in the preceding screenshot. You will notice that the item is recovered to the original space. When an item is recovered, it is removed from the archive space store and moved to the original space from which it was deleted. Purged items are deleted forever and cannot be recovered. Because the deleted items will otherwise be in the temporary store forever, it is a good practice to purge them periodically. It is also recommended that you take regular backups of your data.  

PHP-CLI vs PHP-CGI Most Linux distributions include both versions of PHP when installed, especially if you are using a modern distribution such as CentOS or Mandriva. When writing AGI scripts with PHP, it is imperative that you use PHP-CLI, and not PHP-CGI. Why is this so important? The main issue is that PHP-CLI and PHP-CGI handle their STDIN (standard input) slightly differently, which makes the reading of channel variables via PHP-CGI slightly more problematic. The php.ini configuration file The PHP interpreter includes a configuration file that defines a set of defaults for the interpreter. For your scripts to work in an efficient manner, the following must be set—either via the php.ini file, or by your PHP script: ob_implicit_flush(false); set_time_limit(5); error_log = filename;error_reporting(0); The above code snippet performs the following: Directive Description ob_implicit_flush(false); Sets your PHP output buffering to false, in order to make sure that output from your AGI script to Asterisk is not buffered, and takes longer to execute set_time_limit(5); Sets a time limit on your AGI scripts to verify that they don't extend beyond a reasonable time of execution; there is no rule of thumb relating to the actual value; it is highly dependant on your implementation Depending on your system and applications, your maximum time limit may be set to any value; however, we suggest that you verify your scripts, and are able to work with a maximum limit of 30 seconds. error_log=filename; Excellent for debugging purposes; always creates a log file error_reporting(E_NONE); Does not report errors to the error_log; changes the value to enable different logging parameters; check the PHP website for additional information about this AGI script permissions All AGI scripts must be located in the directory /var/lib/asterisk/agi-bin, which is Asterisk's default directory for AGI scripts. All AGI scripts should have the execute permission, and should be owned by the user running Asterisk. If you are unfamiliar with these, consult with your system administrator for additional information. The structure of a PHP based AGI script Every PHP based AGI script takes the following form: #!/usr/bin/php -q <? $stdin = fopen(‘php://stdin’, ‘r’); $stdout = fopen(‘php://stdout’, ‘w’); $stdlog = fopen(‘my_agi.log’, ‘w’); /* Operational Code starts here */ .. .. ..?> Upon execution, Asterisk transmits a set of information to our AGI script via STDIN. Handling of that input is best performed in the following manner: #!/usr/bin/php -q <? $stdin = fopen(‘php://stdin’, ‘r’); $stdout = fopen(‘php://stdout’, ‘w’); $stdlog = fopen(‘my_agi.log’, ‘w’); /* Handling execution input from Asterisk */ while (!feof($stdin)) { $temp = fgets($stdin); $temp = str_replace("n","",$temp); $s = explode(":",$temp); $agivar[$s[0]] = trim($s[1]); if $temp == "") { break; } } /* Operational Code starts here */ .. .. ..?> Once we have handled our inbound information from the Asterisk server, we can start our actual operational flow. Communication between Asterisk and AGI The communication between Asterisk and an AGI script is performed via STDIN and STDOUT (standard output). Let's examine the following diagram: In the above diagram, ASC refers to our AGI script, while AST refers to Asterisk itself. As you can see from the diagram above, the entire flow is fairly simple. It is just a set of simple I/O queries and responses that are carried through the STDIN/STDOUT data streams. Let's now examine a slightly more complicated example: The above figure shows an example that includes two new elements in our AGI logic—access to a database, and to information provided via a web service. For example, the above image illustrates something that may be used as a connection between the telephony world and a dating service. This leads to an immediate conclusion that just as AGI is capable of connecting to almost any type of information source, depending solely on the implementation of the AGI script and not on Asterisk, Asterisk is capable of interfacing with almost any type of information source via out-of-band facilities. Enough of talking! Let's write our first AGI script.

What we will learn in this article? In this article, we will cover the service module and highlight how it fits in with the sales and opportunities management functionality. The key features, from taking a service call to contracting management, will be explained. In order to establish a practical platform for this, a case study will be expanded to utilize the service module. As a part of this section, a complete workflow will be configured from setting the right parameters in the admin section to connecting the information for service personnel. We will learn about : Key terms - The common terminology related to service management will be covered. There is nothing major waiting for you here. We will simply learn what the terms entail with regards to the SAP system. Service module core functions – In this section, the available functions and features will be put into perspective—what is available and how much we can expect from it. For example, you will learn what service operations mean. Case study and your own project – The available features of the service module will then be implemented for the case study. By doing so, knowledge will be provided to implement the service module in your own business. We will review some guidelines which will enable you to translate the case study implementation into a set of activities for your own project. Key terms Let's start with the key terms related to service and contract management in SAP Business ONE. By looking at the key terms, you will get an understanding of what can be accomplished with this module Service contract templates In the admin section, we can define the service contract templates that can later be used as a basis for actual contracts. Please note the template character. All of the parameters we define here will automatically populate the relevant details in the contract once a template is selected. The following screenshot shows that a contract template can be created not only on a per-customer basis, but also for item groups, and a specific item based on serial numbers. In addition, please note the Reminder setting. You can set a reminder which will provide an alert prior to the expiry of the contract. This way, you can be sure that you contact all customers and allow them to renew their contracts. Serial number contract The most common usage may be the Serial Number contract type. Each product will have a specific contractual service eligibility based on the serial number. Consequently, if a customer purchases an item that is managed by a serial number, a warranty contract template can be associated. This will create a customer equipment card. Customer contract However, please note that this concept does not need to be used only for items and serial numbers. As you can see in the previous screenshot, we can create contract templates for customers and whole item groups. For the case study, I will use this concept to create a service contract for key customers. We can then use the service functionality in SAP to make sure these customers get priority treatment. You see, we can use the service functionality in this creative way to improve our service quality. Item group contract Just as we may decide to use the service module to guarantee a specific response time to customers, we can make sure that a specific product line is managed. For example, if you have a new specifi c product line that requires technical expertise for implementation, then a service contract may be offered to customers. Therefore, all customers who purchase an item that belongs to this group will be eligible to purchase a contract and receive the relevant expert support. Customer equipment card The customer equipment card applies to the contracts that are managed by a serial number. Since the serial number contract applies a unique contract situation for each item, you will need to have the relevant information to be able to categorize a service call. For example, you need to know the serial number to identify the customer and the relevant warranty that remains for the specific serial number. In addition, if a customer calls you, you"ll want to be able to look up all of the serial numbers for this customer. This can be done using the customer equipment card. Please note that a customer equipment card is automatically created if a customer purchases an item that is managed by a serial number. You can assign a service contract when this happens on the level of sales order. Service calls Service calls are incoming service requests from business partners. The following screenshot shows that service calls can have many sources. For example, service calls may come via emails, phone calls, web requests, or any other defined Origin. I am highlighting this because, in essence, you can use the service module for any activity where you want to apply a specifi c response time management. Queues As mentioned above, the service module can be used to manage any kind of service-related activity. Queues allow your personnel to be associated with named groups. In the following screenshot, I have created two queues. The first queue is for 1st Level and the second queue for Resolution and Sales. Consequently, I assign personnel who can best accomplish the relevant tasks to each queue as follows: Knowledge base As you work on service calls, you can build a knowledge base that documents how problems were resolved. For example, if the problem resolution department resolved a problem, it will be documented as a part of the service call. If the service call is for a serialized item, then this knowledge is available to the first-level support the next time a problem is reported for the same item type. Therefore, this can take the workload off of the specialized personnel as they can avoid repetitive tasks. In addition, new employees can benefit from the knowledge already acquired for resolved service calls.

Asterisk has a wonderful, built-in ability to record calls. No additional software is required to make this happen. When Asterisk records a call, both sides of the call are recorded and written out to a file for playback on a computer. Call recording is often performed in call centers to ensure call quality, or to keep calls for later review, should the need arise. Asterisk provides the ability to record all of the calls, or to selectively record calls. In this article, we will look the following:   General recording options Recording calls to extensions Recording calls to queues Recording calls to conferences Maintaining call recordings Before enabling call recording for your PBX, make sure that you are aware of the legalities surrounding call recordings and privacy laws. Call recordings are prohibited in certain places, unless the caller is told that the call will be recorded. For example, in the state of California all of the parties on the call must consent to the call being recorded before it begins. Playing back a message stating that the call is being recorded prior to the call being answered is considered a valid form of consent. Recording formats FreePBX allows calls to be recorded in the following formats: WAV WAV49 ULAW ALAW SLN GSM Each format has its own ratio of file size to recording quality, and certain formats will not play on all of the computers. A comparison between all of the  available formats is as follows:

(For more resources on Plone, see here.) Graphic design tools Any serious skinner needs a graphic design tool with certain capabilities in order to take the design files and assemble them into a finished web site. In particular, layers and the ability to slice pieces of a design and export those pieces are essential. Layers allow a themer to hide pieces not needed in a finished CSS theme, such as text that will eventually become real HTML on a page. Slices, meanwhile, are the pieces of an overall design that are exported during the layer manipulation process. They are the images the end user eventually sees on the rendered page. This is different from cropping, which actually alters the size of the canvas; slices are just pieces of the overall design, cut with precision, exported, and then manipulated with CSS. The most commonly used graphic design tools used for web design are Adobe® Photoshop®, Adobe® Fireworks® (formerly Macromedia) tool, and open source tools such as GIMP. It is not generally recommended to use tools such as Adobe® Illustrator®, Corel Draw and other vector-based packages. Web designs primarily use raster-based media, meaning that raster images are based on pixels and thus scale with loss of clarity. Conversely, vector-based images can be scaled infinitely without degrading, but are typically not appropriate for web design. Adobe Photoshop The most popular tool for processing image files is Adobe Photoshop. The files generated for designs are PSD, or Photoshop Document files. Adobe Photoshop meets the basic requirements of being able to manipulate the vector and raster images, layers, and slices, and offers a lot of additional functionality. The ability to control anti-aliasing and the quality and size of an exported image is essential in web design, and Adobe Photoshop (also, Adobe Fireworks) is quite powerful in this respect. A quick look at the Layers panel illustrates how sections can be grouped together, moved, or be shown or hidden via the "eyeball" icon. This show/hide functionality is very important. One situation where this becomes valuable is when you have a PSD file that indicates graphical buttons with text over them. For accessibility reasons, you may want to render the text as real HTML-rendered text, and not as an image. You need to be able to export the buttons in both their on and off states in order to get a proper rollover effect, and you need to hide the graphical text in order to do this. One site that illustrates this concept is http://greenforall.org. Using Adobe Photoshop, the layers where the text appears on the top navigation were hidden, and just the background on/off images were imported. On the finished web site, the top menu used the background images and real rendered text. The other core functionality that Adobe Photoshop offers is the ability to slice images and export them. The Copper River Watershed Project web site (http://www.copperriver.org) illustrates how slices might be used. The original Adobe Photoshop document is here: If you look closely, you can see a few key slices: the "Go" button next to the search field has been sliced, as has the Tour Our Watershed map and the gradation on the top navigation, which will be tiled horizontally. Below the orange navigation is a long slice that spans from the left-hand shadow over to the right-hand shadow. This image can be used to tile the length of the page. Additionally, the entire Information For... box has been sliced; in this case, for the final implementation, the text overlaying this slice was hidden and replaced with rendered text. If you look at the finished web site, you can see how these slices were applied. Photoshop provides a great deal of power, but in general, you may only use about 20% of the power it offers. You can visit http://adobe.com to see the tutorials on how to use the Adobe Photoshop effectively. Additionally, you may want to investigate Photoshop Elements; it doesn't allow you to slice images for the Web, but for the current price of $139.99, it's still a great tool for many web design activities: http://www.adobe.com/products/photoshopelwin. Adobe Fireworks At the time Macromedia was purchased by Adobe in 2005, the interface was a little clumsy at times, but it did have a basic implementation of layers and slices. Over the past few years, based on the demos available, it appears that the interface has seen some great improvements, though it does not have the same power or market share as Adobe Photoshop has. However, at nearly $400 less than Adobe Photoshop, it's a great option. According to the Adobe web site, "Adobe Fireworks CS4 software is used to rapidly prototype web sites and application interfaces and to create and optimize images for the Web more quickly and accurately. It is ideal for web designers, web developers, and visual designers." It differs from Photoshop in that "Adobe Photoshop software is the industry standard for digital imaging, with a broad array of features and functionality used by photographers, graphic designers, web designers, and many other creative professionals. Fireworks is a much more focused tool, with the features for prototyping vectors and bitmaps for the web and application interfaces." The real selling point here, though, is integration with Adobe Photoshop, as a design may be shared between multiple people, each using different graphical programs. The ability to manipulate the vector and raster images is also important. Additionally, like Adobe Photoshop, Adobe Fireworks provides the ability to work with layers and slices, and preserves many of the settings in an Adobe Photoshop PSD file. It's not as good at compositing and photo manipulation as Photoshop, but is a lot stronger with text, shapes, and final optimization. Selective JPEG optimization is also very handy, and allows you to heavily compress the portions of a JPEG while keeping text legible. Additionally, it's great for generating image maps (not often used in Plone), rollovers, and other common tricks. Finally, it allows you to view your work with either Windows or Mac gamma. Gamma correction basically refers to the ability to correct for differences in how computers (and especially computer monitors) interpret color values. There are two factors here: the ability to predict what an image, say a photograph, will look like on another monitor and the ability to match the colors from different sources on a single page—Adobe Fireworks excels at both. While Adobe Fireworks is not as feature-rich as Adobe Photoshop, it is still an extremely competent tool for slicing and exporting design elements at implementation time, not to mention more affordable. GIMP GIMP, also known as the GNU Image Manipulation Program, can be downloaded for free from http://www.gimp.org. It is a freely distributed program for such tasks as photo retouching, image composition and image authoring, and is covered by the GNU GPL license. According to the GIMP's web site, it can be used as a simple paint program, an expert quality photo retouching program, an online batch processing system, a mass production image renderer, an image format converter, and more. From the perspective of how it compares to the key aspects of Adobe Photoshop® and Adobe Fireworks®, it has full support of layers and channels, plug-ins that allow for the easy addition of new file formats (that is, it can read Adobe Photoshop or Adobe Fireworks files), and best of all, it is open source. You can visit http://www.gimp.org/docs to download the user manual for the current release. GIMP also lists several user groups and resources at http://www.gimp.org/links that may be helpful. Even so, the latest releases are still quite recent, so development is still happening For a free solution to the image processing needs, GIMP is an excellent choice, but weak in terms of the user interface and layer compatibility with Adobe Photoshop. Browser add-ons and important notes Now that you have sense of the tools that are available for manipulating design files and exporting the necessary images for building your web site, let's look at how browsers affect the web site building process, either through add-on tools or through sheer bugginess. It's also worth mentioning that users should reference the A-List of popular browsers to see which browsers are still considered to be supported by web developers: http://developer.yahoo.com/yui/articles/gbs/index.html. This can help to ease the quality assurance load during web site testing. Many of these A-List browsers come with browser-specific tools that allow you to inspect your web site to descry the CSS (Cascading Style Sheets) ID and class selectors, manipulate your CSS on-the-fly, optimize your site, explore color options, and more. We'll look at the available options for three major browsers: Internet Explorer, Firefox, and Safari, but you should always be conscious of general browser penetration statistics so that you know which browsers are still in popular use: http://en.wikipedia.org/wiki/Usage_share_of_web_browsers. Now, let's get back to our key browsers. Internet Explorer From a themer's perspective, Internet Explorer is the most finicky browser against which to implement, as older versions of Internet Explorer followed the W3C's (World Wide Web Consortium's) standards differently than many other popular browsers. According to http://positioniseverything.net, a leading collector of browser fixes, "All browsers have CSS bugs, and IE leads the pack in this area, but that is not the end of the story. Microsoft has seen fit to engineer their browser to deliberately violate the standards in several critical ways. It might just be a misguided attempt to 'make it simple' for newbie coders, or it might be a cynical ploy to crush the competition, but in any case it creates huge headaches for those of us who desire to employ CSS positioning on our pages." While this may be true, many fixes for Internet Explorer have been identified, and thankfully, IE6, one of the more problematic browsers in recent years, is finally becoming obsolete. It was replaced by IE7, which was a vast improvement, but still did not implement the W3C conventions for CSS faithfully. As of this writing, Internet Explorer 8 was released and showing signs of having finally made strides toward real compliance to W3C standards. What this equates to is that web developers tend do their initial browser testing in browsers that are more compliant; that means doing most upfront testing in Firebug and Safari, and then rounding out the testing at the end against IE6, IE7, and IE8. Where possible, it's also important to test against other major browsers and handheld media. For testing against Internet Explorer, IE provides a tool called the Web Developer Toolbar for debugging. It is available for both IE6 and IE7 as an add-on and can be downloaded here: http://www.microsoft.com/downloads/details.aspx?FamilyId=E59C3964-672D-4511-BB3E-2D5E1DB91038&displaylang=en. Web Developer Toolbar will no longer be the tool of choice for IE8, however, instead use the developer tools included with IE8. To use the developer tools in IE8, press Shift+F12 or click the "Developer Tools" icon in the command bar to begin using the tool. For IE6 and IE7, Web Developer Toolbar provides several features for exploring and understanding web pages. These features enable you to: Explore and modify the document object model (DOM) of a web page. Locate and select the specific elements on a web page. Selectively disable the Internet Explorer settings. View HTML object class names, IDs, and details such as link paths, tab index values, and access keys. Outline tables, table cells, images, or selected tags. Validate HTML, CSS, WAI, and RSS web feed links. Display image dimensions, file sizes, path information, and alternate (ALT) text. Immediately resize the browser window to a new resolution. Selectively clear the browser cache and saved cookies. Choose from all objects or those associated with a given domain. Display a fully-featured design ruler to help accurately align and measure objects on your pages. Find the style rules used to set specific style values on an element. Right clicking on a style rule will allow you to trace the rules to a specific CSS file, if one is found. View the formatted and syntax colored source of HTML and CSS. The Developer Toolbar can be popped up within the Internet Explorer browser window or opened as a separate window. If you are using a PC to test your sites, VMware, parallels, or a Windows emulator, you should download the Toolbar from http://go.microsoft.com/fwlink/?LinkId=125120, install it, and restart IE. You can then click the Developer Toolbar icon in the command bar to display or hide the Developer Toolbar. Alternately, you can open the View menu and then use the Explorer Bar menu. In Internet Explorer 7, open the Tools menu and then use Toolbars/Explorer Bars to display or hide the Developer Toolbar. There are a few caveats here: The Developer Toolbar icon may not be visible by default. If you do not see it after restarting Internet Explorer, click the right-facing arrows at the end of the IE7 command bar to view all the available Toolbar buttons. Some menu items are unavailable (grayed out) when running Internet Explorer in Protected Mode on Windows Vista. To use those options, temporarily turn off Protected Mode or right-click the Internet Explorer icon in the Programs menu and choose Run as administrator. In IE6 or in IE7 with tabbed browsing off, using the validation links will navigate the current window to the validation page. To launch the validation links in a new window, open the Tools menu, click Internet Options, and uncheck Reuse windows for launching shortcuts in the Advanced tab, or use IE7 with tabbed browsing enabled. Generally, you can use this tool by expanding the left side of the panel displayed to navigate through your site's structure. It displays CSS IDs and classes in a hierarchical fashion. On the right-hand side, it displays the properties assigned to each of those IDs or classes. You can modify those by using the + icon in the center Attributes section to add a new property and using that to add to or alter the existing CSS. As stated before, the left-hand pane allows you to expand and walk through the structure of your web site. When you refresh, unfortunately, the entire tree closes. To continue troubleshooting a specific element on the page, you must drill down to it again or use the "selector" tool. It's somewhat clumsy, but it works and is invaluable when debugging web pages in Internet Explorer.  

An overview Views are at the heart of Django and hold most of your application logic. They are nothing more than Python functions that take an HTTP request as input and return an HTTP response or error. A mechanism called the dispatcher identifies an incoming URL against a set of URL patterns and their associated view functions. When a match is found, the associated view is called and the request gets handled. Since many views follow a common strategy of loading an object or list, loading a template, rendering the template, and returning a response, Django offers a way of doing this without writing a view function. These generic views are called from the URL dispatcher and go right to the template. Creating the application Before we start looking at views and URLs, let's create a sample application to experiment with. Since most books and examples use blog models as their demos, let's keep things fresh by making our demo a press release application for a company website. The press release object will have a title, body, published date, and author name. Create the data model In the root directory of your project (in the directory projects/mycompany), create the press application by using the startapp command: $ python manage.py startapp press This will create a press folder in your site. Edit the mycompany/press/models.py file: from django.db import modelsclass PressRelease(models.Model): title = models.CharField(max_length=100) body = models.TextField() pub_date = models.DateTimeField() author = models.CharField(max_length=100) def __unicode__(self): return self.title Create the admin file To take advantage of the automatic admin interface that Django gives us, we need to create a file called an admin file. Create a file called admin.py in the mycompany/press directory, adding these lines: from django.contrib import adminfrom mycompany.press.models import PressReleaseadmin.site.register(PressRelease) If you've used Django before version 1.0, this step is new. The admin configuration directives were taken out of the model and put into their own files starting in version 1.0. Add the press and admin applications to your INSTALLED_APPS variable in the settings.py file: INSTALLED_APPS = ( 'django.contrib.auth', 'django.contrib.admin', 'django.contrib.contenttypes', 'djan?go.contrib.sessions', 'django.contrib.sites', 'mycompany.press',) In the root directory of your project, run the syncdb command to add the new models to the database: $ python manage.py syncdb Because we have Django's authentication system listed as one of our installed applications, the initial syncdb process will ask us if we want to create a superuser. Go ahead and create a superuser account; you will be using it later to access the admin site. Configure the URLs Finally, edit the mycompany/urls.py file: from django.conf.urls.defaults import *from django.contrib import adminadmin.autodiscover()urlpatterns = patterns('', (r'^admin/(.*)', admin.site.root),) Add data in the admin application By adding django.contrib.admin to our INSTALLED_APPS setting and creating a URL mapping for it, we can access the admin site by browsing to http://localhost:8000/admin/. Go into the admin app and add two or three press releases so that we have some sample data to work with: Mapping URLs to views When Django accepts an incoming request, one of the first things it does is that it looks at the URL and tries to match it against a group of URL patterns. In order to identify patterns, Django uses regular expressions to see if the URLs follow a known format. Consider these URLs: http://localhost:8000/press/detail/1/ http://localhost:8000/press/detail/2/ These URLs appear to follow a pattern that they start with press/detail/ and end with a number that represents the ID of a press release. (Recall that we don't work with the domain name portion of the URL. Django takes care of this automatically for us and just sends us everything that follows the domain name.) With this pattern, we can add a new line to our mycompany/urls.py file: from django.conf.urls.defaults import *from django.contrib import adminadmin.autodiscover()urlpatterns = patterns('', (r'^admin/(.*)', admin.site.root), (r'^press/detail/d+/$', 'mycompany.press.views.detail'),) If you're not familiar with Python's regular expressions, this new line may look a bit wonky. This is the most important part: r'^press/detail/d+/$' It reads like this: "A string that starts with press/detail/ and ends with one or more digits followed by a slash". The second segment of the new line is the view function that will get called when an incoming URL matches this pattern. In this case, it will be a function called detail in the mycompany/press/views.py file. There's only one problem with this pattern—it recognizes that a number will be at the end of the URL, but doesn't do anything to pass that number to the view when it's called. We can use a Python regular expression group to capture that number: urlpatterns = patterns('', (r'^admin/', include('django.contrib.admin.urls')), (r'^press/detail/(?P<pid>d+)/$', 'mycompany.press.views.detail'),) This grouping syntax looks really funky, but it's easy to understand once you've seen it a few times. (?P ) is the Python syntax for a named group, which allows the regular expression to save the piece that matched, and put a label on it so that we can call it later. The <pid> part is where we assign the label of pid to the ID of the press release that was sent with the URL. In the case of this URL, the named group pid will be equal to 2: http://localhost:8000/press/detail/2/ Any named groups that we get from a URL are passed as arguments to our view function. In this example, our detail function in press/views.py will have a method signature like this: def detail(request, pid): p = PressRelease.object.get(id=pid) .. There are two keyword arguments to the detail function, request and pid. (Django automatically passes the keyword request, which we'll explore a little later.) Because we used a named group in the URL configuration to capture the press release ID, it's passed to our detail function as pid. You can use multiple named groups in your URL patterns to capture multiple pieces of information and pass them to your functions. Note: URL configurations and patterns are usually referred to as URLConf. Handling unmatched URL patterns URLs are matched up with view functions when they match patterns, but what happens when a match isn't found? This URL wouldn't match the patterns we created because it doesn't end in a number: http://localhost:8000/press/detail/abc/ In this case, the URL dispatcher wouldn't match against our pattern and would keep trying other patterns until a match is found. If no match is found, a 404 error is raised. If you have debug set to true (DEBUG=True) in your settings file, you'll see an error message like this: Splitting up the URL configurations We created the URL configurations for the press application in the mycompany/urls.py file. While this is perfectly acceptable, sticking all the configurations into the main urls.py file can get unwieldy for large projects with many applications. It also isn't very modular if we want to share applications with others or use applications that other people distribute. Instead of writing the press release configuration in our main mycompany/urls.py file, let's create a new file at mycompany/press/urls.py: from django.conf.urls.defaults import *urlpatterns = patterns('', (r'^detail/(?P<pid>d+)/$', 'press.views.detail'),) This looks very similar to what we already have, but note that we've dropped press from the beginning of the regular expression. This line will match URLs that start with detail. Open your mycompany/urls.py file and edit the highlighted line: from django.conf.urls.defaults import *from django.contrib import adminadmin.autodiscover()urlpatterns = patterns('', (r'^admin/(.*)', admin.site.root), (r'^press/', include('mycompany.press.urls')),) We've changed the regular expression portion to match URLs that start with press/. If one is found, Django will hop over to the press/urls.py file to try to match the rest of the URL (without the press/ prefix). With this setup, we are telling Django that any URLs that start with press will be handled in a separate urls.py file in the press directory. Creating views Now that we're matching a URL to a view and passing it information, we can look at how a view is structured. Views have two rules you must follow: The view must accept the request object as its first argument. The view must return an HTTP response or an exception. Beyond this, just remember that a view is a standard Python function and you can do just about anything in it that you can do in a Python program. Accepting the request object Our first rule for views states that a view must accept the request object as its first argument. What is this request object? Django automatically creates the request object when a page is requested. It contains data about the incoming HTTP request such as the requestor's IP address, user agent, request method, cookies, GET parameters, POST parameters, and so on. Everything you should need to know about an incoming request will be found in this object. When you build your view functions, always specify request as the first keyword argument: def detail(request): # Python code here If you forget to add request as the first parameter, you'll know quickly because your view will fail to load with some kind of error message about the arguments (the exact error depends on what other keyword arguments you might be using). Responding with an HTTP response The second rule for views is that a view must return an HTTP response or an exception. Let's start by talking about what an HTTP response is. In order for a browser to understand how to render a web page, it looks at some special hidden information called headers, which is sent by the server along with the content or document being requested. These headers tell the browser information such as what kind of web server is sending the response, which version of the HTTP protocol is being used, how big the content is, and what kind of content is being sent. Luckily, we don't have to worry about most of this because the web server and Django take care of it for us. All we have to do is make sure we send the response out of our view using the HttpResponse method. In your mycompany/press/views.py file, add the following lines: from django.http import HttpResponsedef detail(request, pid): return HttpResponse('This is just a test.') Point your browser to http://localhost:8000/press/detail/1/. Here's what it should look like: Obviously, our views are going to be more complicated than this one, but it illustrates how simple they can be. Responding with an exception The second part of our rule said that the view can respond with an exception instead of an HTTP response. When Django encounters an error during the processing of a view, we usually want to return a friendly error message to the user to let them know something went wrong (as opposed to just sending back a blank screen). Usually, these error messages are in the form of 404 or 500 Error pages. 404 errors are also known as page not found errors. Anyone who has spent time surfing the Web has undoubtedly encountered a 404 Error page when clicking an old link that is no longer valid. In traditional HTML publishing, 404 errors popped up when the user requested a filename that wasn't found on the server (that's where the "page" in "page not found" comes from). With Django, we don't have URLs that represent filenames on the server, but we still return a 404 error when the user is looking for a resource that does not exist. Django makes it easy to return a 404 page by returning the error using the HttpResponseNotFound function: from django.http import HttpResponseNotFounddef detail(request, pid): return HttpResponseNotFound('Page Not Found') Similarly, requests that cause errors on the server are usually referred to as 500 errors. (500 is the standard HTTP response code for a server error.) Django also makes it easy to serve a 500 error: from django.http import HttpResponseServerErrordef detail(request, pid): return HttpResponseServerError('An Error Has Occurred.') Putting the views together Now that we know how a view works and what it needs to do, let's write the real view to work with our sample application. Building the basic view In your mycompany/press/views.py file, replace any contents with the following lines: from django.http import HttpResponsefrom django.http import HttpResponseNotFoundfrom mycompany.press.models import PressReleasedef detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' try: p = PressRelease.objects.get(id=pid) return HttpResponse(p.title) except PressRelease.DoesNotExist: return HttpResponseNotFound('Press Release Not Found') If you'd like to test it out, point your browser to http://localhost:8000/press/detail/1/. You should see the title of your press release. Change the number at the end of the press release to an ID that doesn't exist (such as 99) and you should get a Page Not Found error. This view doesn't return a very pretty output, but it follows the rule that the view must serve an HTTP response or an error/exception. The try/except error handling to make sure the press release exists is kind of ugly. Luckily, Django gives us a more elegant way of handling it. Cleaning up the error handling Instead of putting a try/except block around the object lookup, Django has a get_object_or_404 method that will automatically raise an error if the object is not found. Change the highlighted lines in your mycompany/press/views.py file: from django.http import HttpResponsefrom django.shortcuts import get_object_or_404from mycompany.press.models import PressReleasedef detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=pid) return HttpResponse(p.title) That's a much cleaner way of doing things! Note: If you're getting a list instead of an object, Django has a get_list_or_404 method that you can use. We'll see this in a few pages. Adding the template files The last thing we need to do is add a way to load up the response with the output of a rendered template. We're going to load a template file, replace placeholders in that file with our data (called "rendering" the template), and then return the contents of the template as a string as an HTTP response. We create a templates directory at mycompany/templates, and configured the settings.py file to tell Django where to find it: TEMPLATE_DIRS = ( '/projects/mycompany/templates/',) Verify that you have configured your project this way before continuing. With this setting in place, we can load templates relative to this path. Create a directory under the mycompany/templates directory called press. (It's common practice to use subdirectories to group template files by the application they are associated with.) Create a new file at mycompany/templates/press/detail.html and add these lines: <html><head><title>{{ press.title }}</title></head><body><h1>{{ press.title }}</h1><p>Author: {{ press.author }}<br/>Date: {{ press.pub_date }}<br/></p><p>{{ press.body }}</p></body></html> This simple template file has placeholders for our title, author, pub_date, and body fields. When the template is rendered, these placeholders will be replaced with their respective values. Now that we have a template, we can tell the view to use it. Adding the template to the view In our mycompany/press/views.py file, let's add a few lines to load our template. Replace the contents of your file with these lines: from django.http import HttpResponsefrom django.shortcuts import get_object_or_404from django.template import loader, Contextfrom mycompany.press.models import PressReleasedef detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=1) t = loader.get_template('press/detail.html') c = Context({'press': p}) rendered_template = t.render(c) return HttpResponse(rendered_template) In the function, we're retrieving the press/detail.html template file and creating a special data object called Context. So for now, just understand that it passes data to the template so that it can be rendered. The context object in this example passes our press release object to the template in a variable called press. Our template gets rendered into a string called rendered_template that is sent back to the browser via HttpResponse the same way we sent back simple lines of text in previous examples. The rendered_template variable was used for clarity. You can omit it and just return the response like this: def detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=1) t = loader.get_template('press/detail.html') c = Context({'press': p}) return HttpResponse(t.render(c)) Point your browser to the URL http://localhost:8000/detail/1/. You should see something like this depending on what you entered earlier into the admin site as sample data: Creating the list view and template In addition to displaying the detail for a specific press release, we'll also need a way to display a list of press releases. The steps to add this will be very similar to what we just did to add our detail view. In your mycompany/press/views.py file, add the highlighted lines: from django.http import HttpResponsefrom django.shortcuts import get_object_or_404from django.shortcuts import get_list_or_404from django.template import loader, Contextfrom mycompany.press.models import PressReleasedef detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=1) t = loader.get_template('press/detail.html') c = Context({'press': p}) return HttpResponse(t.render(c))def press_list(request): ''' Returns a list of press releases ''' pl = get_list_or_404(PressRelease) t = loader.get_template('press/list.html') c = Context({'press_list': pl}) return HttpResponse(t.render(c)) In your mycompany/press/urls.py file, add the highlighted line: from django.conf.urls.defaults import *urlpatterns = patterns('', (r'detail/(?P<pid>d+)/$','mycompany.press.views.detail'), (r'list/$', 'mycompany.press.views.press_list'),) Any incoming request starting with press/ will be sent to our press/urls.py file. If the remaining part of the URL is list/, it will be handled by the press_list function in our press/views.py file. If the remaining part is detail/<number> (such as detail/1 or detail/2), it will be handled by the detail function. Finally, create a new file at mycompany/templates/press/list.html: <html><head><title>Press Releases</title></head><body><h1>Press Releases</h1><ul>{% for press in press_list %}<li><a href="/press/detail/{{ press.id }}/">{{ press.title }}</a></li>{% endfor %}</ul></body></html> Point your browser to the URL http://localhost:8000/press/list/. You should see something like this, depending on what you entered earlier into the admin site: Using generic views to shorten development time What we've done so far in this article is pretty standard for web application development: We created a view to load an object by its ID. We created a view to load a list of objects. We retrieved our object using the data sent in from the URL or retrieved a list of objects. We loaded a template file. We rendered the template. We returned an HTTP response. Because these actions are so common, Django has a way to cut out the whole step of writing a view, called generic views. Generic views are called from the URL configuration file, which allows you to go right from the URL pattern to your template. Generic views come in a few types: Simple List/detail Date-based Create/update/delete We won't be covering the date-based or create/update/delete generic views. But after reading this article, you'll be well-prepared to read about them in the online documentation. Simple generic views The two simple generic views that handle loading of a template don't require any data lookup (going directly to a template) and redirecting from one URL to another. Loading a template directly If you just need to load and render a template when a URL is requested, you can use the direct_to_template generic view. For example, let's build a robots exclusion file (aka a robots.txt file) that search engine spiders will request at http://localhost:8000/robots.txt. (Search engines wouldn't index pages on a localhost domain, but pretend for this example that they would.) Since the file is rarely changed after being created, you may not want the overhead of a database lookup to serve it, so you just want to render a template when the URL is requested. Create a new file at mycompany/templates/robots.txt and add these lines: User-agent: *Disallow: /admin This very simple example will prevent spiders from trying to index your admin path (visit robotstxt.org for more info on how exclusion files work). In your mycompany/urls.py file, add the highlighted lines: from django.conf.urls.defaults import *from django.contrib import adminadmin.autodiscover()urlpatterns = patterns('', (r'^admin/(.*)', admin.site.root), (r'^press/', include('mycompany.press.urls')), (r'^robots.txt$', 'django.views.generic.simple.direct_to_template', 'template': 'robots.txt'}), ) Point your browser to the URL http://localhost:8000/robots.txt/. You'll get a response that looks like this:

Activating the Administration Interface The administration interface comes as a Django application. To activate it, we will follow a simple procedure that is similar to how we enabled the user authentication system. The admininistration application is located in the django.contrib.admin package. So the first step is adding the path of this package to the INSTALLED_APPS variable. Open settings.py, locate INSTALLED_APPS and edit it as follows: INSTALLED_APPS = ( 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'django.contrib.admin', 'django.contrib.comments', 'django_bookmarks.bookmarks',) Next, run the following command to create the necessary tables for the administration application: $ python manage.py syncdb Now we need to make the administration interface accessible from within our site by adding URL entries for it. The administration application defines many views, so manually adding a separate entry for each view can become a tedious task. Therefore, Django provides a shortcut for this. The administration interface defines all of its URL entries in a module located at django.contrib.admin.urls, and we can include these entries in our project under a particular path by using a function called include(). Open urls.py and add the following URL entry to it: urlpatterns = ( # Admin interface (r'^admin/', include('django.contrib.admin.urls')),) This looks different from how we usually define URL entries. We are basically telling Django to retrieve all of the URL entries in the django.contrib.admin.urls module, and to include them in our application under the path ^admin/. This will make the views of the administration interface accessible from within our project. One last thing remains before we see the administration page in action. We need to tell Django what models can be managed in the administration interface. This is done by defining a class called Admin inside each model. Open bookmarks/models.py and add the highlighted section to the Link model: class Link(models.Model): url = models.URLField(unique=True) def __str__(self): return self.url class Admin: pass The Admin class defined inside the model effectively tells Django to enable the Link model in the administration interface. The keyword pass means that the class is empty. Later, we will use this class to customize the administration page, so it won't remain empty. Do the same to the Bookmark, Tag and SharedBookmark models; append an empty class called Admin to each of them. The User model is provided by Django and therefore we don't have control over it. Fortunately however, it already contains an Admin class so it's available in the administration interface by default. Next, launch the development server and direct your browser to http://127.0.0.1:8000/admin/. You will be greeted by a login page. Remember we need to create a superuser account after writing the database model. This is the account that you have to use in order to log in: Next, you will see a list of the models that are available to the administration interface. As discussed earlier, only models with a class named Admin inside them will appear on this page: If you click on a model name, you will get a list of the objects that are stored in the database under this model. You can use this page to view or edit a particular object, or to add a new one. The figure below shows the listing page for the Link model. The edit form is generated according to the fields that exist in the model. The Link form, for example, contains a single text field called Url. You can use this form to view and change the URL of a Link object. In addition, the form performs proper validation of fields before saving the object. So if you try to save a Link object with an invalid URL, you will receive an error message asking you to correct the field. The figure below shows a validation error when trying to save an invalid link: Fields are mapped to form widgets according to their type. Date fields are edited using a calendar widget for example, whereas foreign key fields are edited using a list widget, and so on. The figure below shows a calendar widget from the user edit page. Django uses it for date and time fields: As you may have noticed, the administration interface represents models by using the string returned by the __str__ method. It was indeed a good idea to replace the generic strings returned by the default __str__ method with more helpful ones. This greatly helps when working with the administration page, as well as with debugging. Experiment with the administration pages; try to create, edit and delete objects. Notice how changes made in the administration interface are immediately reflected on the live site. Also, the administration interface keeps track of the actions that you make, and lets you review the history of changes for each object. This section has covered most of what you need to know in order to use the administration interface provided by Django. This feature is actually one of the main advantages of using Django; you get a fully featured administration interface from writing only a few lines of code! Next, we will see how to tweak and customize the administration pages. And as a bonus, we will learn more about the permissions system offered by Django.