How-To Tutorials

Introduction to Business Rules Management Let us start by understanding some key concepts around business rules. What are Business Rules? Business rules can be defined as the key decisions and policies of the business. Rules are virtually everywhere in an organization; an example is the rule in a bank to deny a loan for a customer if his or her annual income is less than $15,000. We can generally categorize business rules under the following categories: Business Policies: These are rules associated with general business policies of a company, for example, loan approval policies, escalation policies, and so on. Constraints: These are the rules which business has to keep in mind, and work within the scope of while going about their operations. Rules associated with regulatory requirements will fall under this category. Computation: These are the rules associated with decisions involving any calculations, for example, discounting rules, premium adjustments, and so on. Reasoning capabilities: These are the rules that apply logic and inference course of actions based on multiple criteria. For example, rules associated with the up-sell or cross-sell of products and services to customers based on their profile. Allocation Rules: There are some rules that are applicable in terms of determining the course of action for the process, based on information from the previous tasks. They also include rules that manage the receiving, assignment, routing, and tracking of work. Business Rules Anatomy To understand the anatomy of a business rule, we can divide a business rule primarily into the following four blocks: Definitions of Terms: This helps in providing a vocabulary for expressing the rules. Defining a term acts as the category for the rules. For example, customer, car, claims, and so on define the entities for the business. Facts: These are used to relate terms in definitions with each other. For example, a customer may apply for a claim. Constraints: These are the constraints, limitations, or controls on how an organization wants to use and update the data. For example, for opening an account, a customer's passport details or social security details are required. Inference: This basically applies to logical assertions such as 'if X, then Y' to a fact, and infers new facts. For example, if we have a single account validation rule (if an applicant is a defaulter, then the applicant is high-risk), and we know that Harry (the applicant) has defaulted earlier on his payments for other bank services, we can infer that Harry is a high-risk customer. Automating Business Rules As we discuss the externalization and automation of business rules, it's important to understand the distinction between implicit and explicit rules. An implicit rule can be viewed as a rule that is a part of a larger context within the system. It's like multiple rules that are implemented in traditional applications to implement decision logic, for example, assessing the risk level for a loan. Its implementation is usually part of the application it is being developed for, and is never considered beyond the scope of the application, perhaps to be re-used. So Typically, in the IT world, these implicit rules are embedded within the complex application code and spread across multiple systems, making it extremely difficult to introduce changes quickly, and without creating a domino effect across systems. Some of these issues can be resolved by implementing a Business Rules Management System (BRMS) in collaboration with the BPM system in place. This allows the decision logic, which is being used by the process during its execution, to be driven by a central repository where all the rules are stored and managed. This repository provides a way to abstract the decision logic from the applications, and helps in managing this logic centrally, allowing for better management and flexibility for change and re-use. Hence, these rules are explicit in nature. For the loan approval example, business rules such as these would traditionally be embedded in application code, and might appear in an application as follows: public boolean checkAnnualIncome(Customer customer){boolean declineLoan = false;int income = customer.getincome();if( income < 10000 ){declineLoan = true;}return declineLoan;} The above example shows that this rule is obviously difficult for the business users to understand. In today's world, with the need for an organization to be agile, (considering our previous example) the business has to wait for weeks before a small change can be implemented by IT. What is required is the ability of the business users to define and control their own rules, and to be able to get the changes out in the market faster. Business Rules Management and related technology tries to solve this problem. Automating Business Rules for Business Issues Automation of business rules via BRMS is ideal for use, where the following issues are being faced by an organization: Dynamism and Volatility: Companies need to repeatedly change business policies, procedures, and products to meet the market needs. In this case, the rules change very dynamically, and having a BRMS can help in implementing these changes faster, and reducing the time to market and cost of implementation. Time to Market: In this case, the organization might want a particular set of changes to be released quickly due to market pressure, or to gain a competitive advantage. So, Even though the rules are not changed very often, a delay in their implementation could lead to a serious business loss. In this case, the organization needs to have the ability to get these changes in quickly, without roadblocks, which can be addressed by a BRMS. Regulatory Compliance: Failure to comply with regulatory requirements such as Anti-Money Laundering (AML) laws can result in millions of dollars in fines, and legal issues for the organizations. To solve these issues, institutions can combine business rules with SOA to create an effective strategy for enforcing compliance. Business rules technology helps in implementing these rules quickly, and helps them to be kept up–to-date across an enterprise. Business Participation: There could be rules which might be better off being controlled and owned by the business users. In this case, a BRMS can expose certain rules to be managed and edited by selected business users, providing an easy to use interface. Rules related to product configuration, customer eligibility, discounts and so on, are some examples where business users can manage the rules, and change them as required by changing scenarios. Complexity: Some scenarios, such as complex product and service pricing, require extremely complex dependencies between several rules to implement the scenario logic. These kinds of rules are best suited for implementation inside a BRMS rather than a procedural language, as is being done traditionally. Telecom Fraud Management, for example, is an area where rules management is being used along with BAM to identify potential frauds. There are similar applications in credit card and banking industries. Consistency: Rules managed centrally provides a more consistent way of managing certain policies requiring re-use and consistency across the enterprise. This is especially true in cases where inconsistency was an issue due to multiple applications, databases, and different lines of businesses. Business Rules Management, BPM, and SOA Business Rules Management, BPM, and SOA share a synergistic relationship, especially, when used together to provide agility to an organization. The term 'Agility' can be defined as "the ability of an enterprise to sense and predict change in their environment and respond quickly, efficiently, and effectively to that change". Agility, requires the organization to be flexible enough in introducing change and in modifying their current operations, to achieve higher levels of performance or output. A process-driven approach to SOA allows business users to introduce changes to the process for faster execution, and with less cost. This value is amplified by using a Business Rules platform alongside process orchestration. If we look at the BPM reference architecture again, rules functionality features in various layers of the architecture, in the initial rules discovery phase, during process mapping, and in its orchestration in the SOA environment. Business Rules-related technologies have been in the market for a number of years now. However, with the acceptance of BPM and SOA as enablers for increasing an organization's agility, today's enterprises are increasingly looking at using rules management to externalize their rules. Business rules management helps automate decisions and apply policies within processes. Automation of these decisions requires determining the meaning of a given situation, and applying a business policy in response to this. Business rules platforms provide tools to define this 'reasoning' logic for use by either developers or business analysts, and business stakeholders. Organizations are looking at Business Rules Management to deploy rules related to policy decisions, work allocation, compliance and control, business exception management, and even data validation. For example, a major financial services company uses business rules to apply privacy and anti-fraud policies to all of its transactions. Even more, these Business Rules are being considered as an asset for an organization that should be managed centrally and re-used across departments and systems, instead of being hard-coded into an application. So, it is important to ensure that business rules have a place in your SOA. Carefully defining and exposing your rules as services will enable all of the applications and services within your architecture to have simple access to a common rules repository. From an SOA perspective, before beginning a business rules implementation, you should: Incorporate a business rules platform into your SOA: This would be a service-enabled repository of your business rules, where instead of data you would maintain and execute rulesets using a business rules engine. Create standards and best practices for developing business rules: To maximize benefits from your rules implementation, you should focus on developing common standards and best practices for discovery, design, development, and interfacing of your rules. Some of the best practices for writing and designing business rules are: Declarative: Business rules should be declared, and not stated as procedures as in coding. How a rule will be enforced should not be part of a rule definition. For example, "If the customer is a premium customer, offer him further 5% discount." Precise: It's easier for business rules definitions to be misinterpreted due to the use of natural language syntax by business. One business rule should be open to only one interpretation, and would need rephrasing if it was found to be ambiguous. Consistency and non-redundancy: Business rules should be consistent and not conflict other rules. Similarly, you should look out for business rules that are redundant. Business Focused and Owned: Business rules should be declared using the business vocabulary so that they can understood by relevant business stakeholders. Avoid using technical jargons in business rules. Also business rules are best left under the ownership of the business, community, as that is the source for the rules. Key Considerations for Selecting a BRMS The following are some key considerations when selecting a BRMS to work with BPM and SOA: Standards-based Integration capability: The ability to integrate with the SOA landscape using a service layer. Business User Interface: The ability to provide the capability for business users to access and modify business rules through a user-friendly interface. Rule Language: The ability to provide support for natural languages for easily expressing a complex set of rules. Performance: The ability to provide support for high-volume transactions for mission-critical applications, which is normally measured in terms of the number of rules processed per second. Rules Monitoring and Reporting: The ability to feature support for rules debugging, rules reporting, and real time monitoring of rules. Rules Repository: The ability to provide a centralized repository for storing all rule-specific artifacts. The repository should also support change management by storing different versions of rules, and providing audit capabilities. Key components of a BRMS—A Brief Look into Oracle Business Rules Typically, a BRMS will comprise four main components: Business UI: This is a user interface component for writing and editing business rules. Typically, it will be a web-based interface for business users to log in and access existing business rules, create new ones, and so on. Rules Development Environment: Developers will be working in this environment to convert business rules defined by business users into code that can be implemented in the business rules engine. This will be also an environment where the service layer for the rules will be defined and implemented for integration with other applications and SOA components. Rules Repository: This will be a centralized repository where all rules-related information will be stored. Rules Execution Engine: This is the heart of the rules management system and will be responsible for executing the business rules in the run time environment. In SOA terms, this component will receive request for rules processing from the business process orchestration environment, based on which, it will run appropriate rules and provide decision information that will be sent back to the orchestration layer. Oracle also provides a suite of components under its Oracle Business Rules product to support rules management and execution, which are as follows: Oracle Rule Author: Rule Author provides a web-based graphical authoring environment that enables the easy creation of business rules via a web browser. The application developer uses Rule Author to define a data model and an initial set of rules. The business analyst uses Rule Author either to work with the initial set of rules, or to modify and customize the initial set of rules according to business needs. Using Rule Author, a business analyst can create and customize rules with little or no assistance from a programmer. Rules Engine: This is the heart of the rules system and executes and manages rules in a proper and efficient manner. This allows inference-based rule execution, based on the very popular Rete algorithm. The Rete algorithm is an efficient pattern-matching algorithm used for rules and facts, and stores partially-matched results in a single network of nodes in current working memory, allowing the rules engine to avoid unnecessary rechecking when facts are deleted, added, or modified. Oracle's rules engine provides a data-driven forward-changing system. This means that the facts will determine which rules can be triggered. When a particular rule is triggered, based on pattern matching within a set of facts, the rule may further add new facts. The new facts are again run against the rules as an iterative process untill it reaches an end state. This allows rules to be interlinked and triggered in a cycle, also referred to as an inference cycle.The rules engine also provides a web service interface with its SOA environment using 'Decision Services', which is available in a JDeveloper environment during the coding of business processes in BPEL. This can also be used to make a web service call to rules running in the rules engine. It also exposes a Rules API, which is based on JSR 94, a runtime specification for rules engines to integrate business rules application with other applications in an organization. Rule Repository: A rule repository is the database that stores business rules. The Oracle rules repository allows rules to be grouped as rulesets, and make it part of the rules dictionary in a central repository. These dictionaries can be versioned for better governance. Oracle's rules repository supports a WebDAV (Web Distributed Authoring and Versioning) repository and a file repository. Rules SDK: This allows users to develop and integrate the Rules Repository in to a custom authoring environment. This component also allows the development of a customized UI for business users to access and update the Rules repository, if required.

Knowledge requirements A candidate appearing for the CISSP exam should have knowledge in the following areas that relate to access control: Control access by applying concepts, methodologies, and techniques Identify, evaluate, and respond to access control attacks such as Brute force attack, dictionary, spoofing, denial of service, etc. Design, coordinate, and evaluate penetration test(s) Design, coordinate, and evaluate vulnerability test(s) The approach In accordance with the knowledge expected in the CISSP exam, this domain is broadly grouped under five sections as shown in the following diagram: Section 1: The Access Control domain consists of many concepts, methodologies, and some specific techniques that are used as best practices. This section coverssome of the basic concepts, access control models, and a few examples of access control techniques. Section 2: Authentication processes are critical for controlling access to facilities and systems. This section looks into important concepts that establish the relationship between access control mechanisms and authentication processes. Section 3: A system or facility becomes compromised primarily through unauthorized access either through the front door or the back door. We'll see some of the common and popular attacks on access control mechanisms, and also learn about the prevalent countermeasures to such attacks. Section 4: An IT system consists of an operating system software, applications, and embedded software in the devices to name a few. Vulnerabilities in such software are nothing but holes or errors. In this section we see some of the common vulnerabilities in IT systems, vulnerability assessment techniques, and vulnerability management principles. Section 5: Vulnerabilities are exploitable, in the sense that the IT systems can be compromised and unauthorized access can be gained by exploiting the vulnerabilities. Penetration testing or ethical hacking is an activity that tests the exploitability of vulnerabilities for gaining unauthorized access to an IT system. Today, we'll quickly review some of the important concepts in the Sections 1, 2,and 3. Access control concepts, methodologies, and techniques Controlling access to the information systems and the information processing facilities by means of administrative, physical, and technical safeguards is the primary goal of access control domain. Following topics provide insight into someof the important access control related concepts, methodologies, and techniques. Basic concepts One of the primary concepts in access control is to understand the subject and the object. A subject may be a person, a process, or a technology component that either seeks access or controls the access. For example, an employee trying to access his business email account is a subject. Similarly, the system that verifies the credentials such as username and password is also termed as a subject. An object can be a file, data, physical equipment, or premises which need controlled access. For example, the email stored in the mailbox is an object that a subject is trying to access. Controlling access to an object by a subject is the core requirement of an access control process and its associated mechanisms. In a nutshell, a subject either seeks or controls access to an object. An access control mechanism can be classified broadly into the following two types: If access to an object is controlled based on certain contextual parameters, such as location, time, sequence of responses, access history, and so on, then it is known as a context-dependent access control. In this type of control, the value of the asset being accessed is not a primary consideration. Providing the username and password combination followed by a challenge and response mechanism such as CAPTCHA, filtering the access based on MAC adresses in wireless connections, or a firewall filtering the data based on packet analysis are all examples of context-dependent access control mechanisms. Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) is a challenge-response test to ensure that the input to an access control system is supplied by humans and not by machines. This mechanism is predominantly used by web sites to prevent Web Robots(WebBots) to access the controlled section of the web site by brute force methods The following is an example of CAPTCHA: If the access is provided based on the attributes or content of an object,then it is known as a content-dependent access control. In this type of control, the value and attributes of the content that is being accessed determines the control requirements. For example, hiding or showing menus in an application, views in databases, and access to confidential information are all content-dependent.

Building the Profile The Content Profile module creates a new content type called Profile when it is enabled. By default, this content type is set to be used as a profile. We need to complete a few additional steps to make our profile fully functional. Edit the default settings for the Profile content type Configure the base Content Profile settings Add any required fields to the Profile content type Add any taxonomy terms to the Profile content type Assign rights to create and edit the Profile content type Edit the Settings of the Profile Content Type As mentioned above, when the Content Profile module is enabled, it creates a new content type named Profile. To use this new node type effectively, we need to change the default settings. To do this, click on the Administer | Site building | Content types link, or navigate to admin/content/types. Click the Edit link for the Profile content type. The Automatic Nodetitles module—enabled earlier in the first part of  this article—adds a new fieldset labeled Automatic title generation at the top of the administrative screens where we edit content types. As shown in the preceding screenshot, we have two options. For the first option, we want to select Automatically generate the title and hide the title field. For the second option—Pattern for the title—we should enter [author-name]'s profile. [author-name] is a token; when the node is created, the token will be replaced by the username of the person creating the node. So, if a user named Jill created the profile node, the title would be Jill's profile. The Token module allows us to use a wide range of tokens in addition to [author-name]. To see the full list of available tokens, expand the Replacement patterns fieldset as indicated in the preceding screenshot by Item 1. The settings listed here also need to be adjusted: In the Submission form settings section, delete the Body field label. We do not want this node type to have a body field; we will add all needed fields using CCK In the Workflow settings section, set the Default options to Published, and Attachments to Disabled In the Comment settings section, set the Default comment settings to Disabled After you have made the necessary adjustments, click the Save content type button to submit the form and save your changes. Configure the Base Content Profile Settings To configure the base Content Profile settings, click on the Administer  Site building | Content types link, or navigate to admin/content/types. Click the Edit link for the Profile content type. Then, click the Content Profile tab. The base settings allow us to configure how the node profile will be displayed on the user profile page. As shown in the preceding screenshot, in the User page display style section we have four options: Don't display this content profile on the user account page—only select this option if you will be overriding the core user profile page via the theming layer. This is an advanced theming technique; refer to the handbook page on overriding user profiles at http://drupal.org/node/35728. Display it as link to the profile content—select this option if you only want to link to the full profile node from the user profile page. Display the full content—this option displays the full node on the user profile page. Display the content's teaser—this option displays the teaser view on the profile page. As discussed later in this section, this option provides us some flexibility not found in the other options. For our example, choose this option. The final two options—Include an edit link to the display and Show a link to the content profile creation page, if there is no profile—should both be selected, as they improve usability. The Weight can be left at 0. When these settings have been adjusted as needed, click the Submit button to save the changes. Add Fields to the Profile Content Type Now that we have edited the defaults of the Profile node type, and adjusted the base settings of the Content Profile, we are ready to add fields and taxonomy terms to our profile. The CCK fields and Taxonomies will provide structure to our user profiles. For this example, we want to extend our profile by adding two fields, and one vocabulary. The fields we will add will both be text fields; one for a Brief bio, and the second for a Full bio. We will also add a Vocabulary to the Profile content type called Interests. Adding this vocabulary is covered in the next section of this article. Add the Brief Bio Field To add the text fields, go to the Content Types administration page by clicking the Administer | Content Management | Content Types link, or by navigating to admin/content/types. Click the manage fields link for the profile content type. In the Add section, we want to add a New field. Enter the following values: Label: Brief bio Field name: brief_bio Field type: text Widget type: text area (multiple rows) Click the Save button; this brings up the admin screen where you can configure the field. As shown in the preceding screenshot, the form to configure the text field has two sections: Profile settings and Global settings. Adjusting the Profile Settings In the Profile settings, we have two options; enter the values specified below: Rows: 3 Help text: Enter your brief bio. 500 characters maximum For this example, we do not need to set any Default value. Adjusting the Global Settings In the Global settings, we have four options; enter the values specified below: Required: No; leave unchecked Number of values: 1 Text processing: Plain text Maximum length: 500 For this example, we do not need to set any Allowed values. Once the field has been configured as needed, click the Save field settings button to save your changes. Adding the Full Bio Field Adding the Full Bio is nearly identical to adding the Brief bio. When adding the field, use the following values: Label: Full bio Field name: full_bio Field type: text Widget type: text area (multiple rows) Click the Save button; this brings up the admin screen where you can configure the field. In the Profile settings, enter: Rows: 5 Help text: Enter your full, extended biography. In the Global settings, we enter: Required: No; leave unchecked Number of values: 1 Text processing: Filtered text (user selects input format) Maximum length: none, leave blank Once the field has been configured as needed, click the Save field settings button to save your changes. Adjusting the Field Display As we discussed above when we configured the base options for Content Profiles, we want to show the node teaser on the user profile page. To take advantage of this option, we need to configure how we display our fields. To do this, go to the Content Types administration page by clicking the Administer | Content Management | Content Types link, or by navigating to admin/content/types. Click the edit link for the profile content type, and then, click the Display fields tab. As seen in the preceding screenshot, you can control how fields are displayed in the Teaser view and in the Full node view. In the settings shown in the preceding screenshot, we have set the Brief bio to show on the Teaser view (that is, on the user profile page), and the Full bio to display on the Full node view (that is, when the entire profile is being viewed). Our settings display a truncated overview on the user profile page, with a link to the more detailed full node view. Add Taxonomy Terms to the Profile Content Type As described above, we want to add an Interests vocabulary. To add new vocabularies, click on the Administer | Content management | Taxonomy| link, or navigate to admin/content/taxonomy. Click the Add vocabulary tab. Adding the Interest Vocabulary For Interests, enter the following values: Vocabulary name: Interests Description: none, leave blank Help text: Describe your interests. Separate each interest with a comma Content types: select Profile; leave others unchecked Settings: select Tags; leave others unchecked Weight: -6 Click the Save button to create the new vocabulary. Assign Rights to Profile Nodes Click on the Administer  User Management | Roles| link, or navigate to admin/user/roles. Select the role(s) that you would like to be able to create node-based profiles. Generally, users should be given the rights to create profile content, and edit own profile content. This will allow users to create their own profiles, and update them as needed, but also protects users from accidentally deleting their profile. Only site administrators or especially trusted users should be given the rights to edit any profile content or delete any profile content.

Hibernate allows transparent persistence, which means the application is absolutely isolated from the underlying database storage format. Three players in the Hibernate scene implement this feature: Hibernate dialect, Hibernate types, and HQL. The Hibernate dialect allows us to use a range of different databases, supporting different, proprietary variants of SQL and column types. In addition, HQL allows us to query persisted objects, regardless of their relational persisted form in the database. Hibernate types are a representation of databases SQL types, provide an abstraction of the underlying database types, and prevent the application from getting involved with the actual database column types. They allow us to develop the application without worrying about the target database and the column types that the database supports. Instead, we get involved with mapping Java types to Hibernate types. The database dialect, as part of Hibernate, is responsible for transforming Java types to SQL types, based on the target database. This gives us the flexibility to change the database to one that may support different column types or SQL without changing the application code. Built-in types Hibernate includes a rich and powerful range of built-in types. These types satisfy most needs of a typical application, providing a bridge between basic Java types and common SQL types. Java types mapped with these types range from basic, simple types, such as long and int, to large and complex types, such as Blob and Clob. The following table categorizes Hibernate built-in types with corresponding Java and SQL types: Java Type Hibernate Type Name SQL Type Primitives Boolean or boolean boolean BIT true_false CHAR(1)('T'or'F') yes_no CHAR(1)('Y'or'N') Byte or byte byte TINYINT char or Character character CHAR double or Double double DOUBLE float or float float FLOAT int or Integer integer INTEGER long or Long long BIGINT short or Short short SMALLINT String java.lang.String string VARCHAR character CHAR(1) text CLOB Arbitrary Precision Numeric java.math.BigDecimal big_decimal NUMERIC Byte Array byte[] or Byte[] binary VARBINARY   Time and Date java.util.Date date DATE time TIME timestamp TIMESTAMP java.util.Calendar calendar TIMESTAMP calendar_date DATE java.sql.Date date DATE java.sql.Time time TIME java.sql.Timestamp timestamp TIMESTAMP Localization java.util.Locale locale VARCHAR java.util.TimeZone timezone java.util.Currency currency Class Names java.lang.Class class VARCHAR Any Serializable Object java.io.Serializable Serializable VARBINARY JDBC Large Objects java.sql.Blob blob BLOB java.sql.Clob clob CLOB

Model Devices When we talk about Zenoss, two related but different words often come up, monitoring and modeling. Monitoring refers to the availability of the device and answers the question, "Is the device accessible?" Modeling defines a relationship between devices and identifies the components available on a device, such as services, interfaces, and file systems. Zenoss models devices via SNMP, SSH, port scan, and telnet and gathers information via collector plug-ins. Each class has a default set of collector plug-ins that tells Zenoss how to model the devices assigned to the class. We can add or remove collector plug-ins at the device level for individual changes or at the class level for all the devices in the class. The collector plug-in names reflect the monitoring protocol they are used for. All the SNMP collectors contain "snmp" in the name. The SSH and telnet plug-in names contain "cmd," and the port scan plug-in contains "portscan" in the name. We'll step through modeling examples for SNMP, SSH, and port scan; however, we'll skip telnet because it's similar to SSH. SNMP Zenoss defaults to SNMP monitoring, and the monitored device needs to have SNMP installed and configured to work properly. Zenoss supports SNMP v1, v2c, and v3. The example commands used in this section to troubleshoot SNMP specify v1. Test SNMP If we're unsure of our SNMP setup, we can test it by running the snmpwalk command to retrieve the values of the MIB tree on the monitored device. We'll demonstrate both working and broken SNMP configurations on the MillRace network. From the Device List, select the device named Coyote. From the Device Status page menu, choose Run Commands > snmpwalk. A new window opens and we see the results of the snmpwalk command as shown in the following screenshot. Now we select the device Bobcat from the Device List view. Run the snmpwalk command from the Device Status page. This time, we receive a Timeout error, which indicates that we have a problem with SNMP on the device Bobcat as shown in the following screenshot. Assuming that SNMP is properly configured on the device and that the monitored device accepts traffic on port 161, we may need to update the device's community string. To update the community: Select the device from the Device List view. From the Device Status page menu, select More > zProperties. Find the Community field and enter the correct value. Save the changes. After updating the SNMP community string in the zProperties, we run the snmpwalk command again to see if we have fixed the problem. If we continue to encounter problems getting Zenoss to model a device with SNMP, we can try to narrow down the problem by running the following snmpwalk command from the monitored devices shell prompt: snmpwalk -v1 -c public localhost system Replace public with the correct community string. If the command is successful when using localhost, edit the snmpd configuration file. As root, edit /etc/default/snmpd or /etc/default/snmp and remove 127.0.0.1 from the following line: SNMPDPORTS = '-Lsd -Lf /dev/null -u snmp -I -smux -p /var/run/snmpd.pid 127.0.0.1' After editing the /etc/default/snmpd file, restart the snmpd service as root. For example: /etc/init.d/snmpd stop/etc/init.d/snmpd start Retest the snmpwalk command to confirm that SNMP is working correctly.Windows users can run wbemtest from the command line to test SNMP. Windows Considerations In order to collect information from WMI,regarding the Windows SNMP installation we need to configure the zProperties for the Windows device. Navigate to the Windows device and open the zProperties page by selecting the More > zProperties from the page menu. Scroll to the bottom of the page and make the following changes: Set zWinEventLog to true. Enter the Windows user's password in the zWinPassword field. Enter the user name with administrative rights in the zWinUser field in the following formats: .user for local user accounts DOMAINuser for domain user accounts Set zWMIMonitorIgnore to false. Save the changes, and Zenoss is ready to model the information on the Windows device. We can force a model by selecting Manage > Model Device from thepage menu. SNMP Collector Plug-ins The Collector Plug-ins assigned to the device determines how Zenoss models the device. Let's take a look at our example device Coyote and see what collectors are currently assigned. From the Device Status page for Coyote, select More > Collector Plug-ins from the page menu. A page showing the assigned collector plugi-ns displays in the left column of the page with an Add Fields link on the right. When we click on the Add Fields link, a column of unassigned plug-ins appears and the link name changes to Hide Fields as shown in the following screenshot. The plug-in names are intuitive in that the name suggests the type of information we expect to be modeling. For example, zenoss.snmp.IpServiceMap returns a list of active IP services on the device, such as HTTP. The Dell specif?i c plugi-ns retrieve more detailed information from Dell devices using OpenManage, and the HPplugi-ns provide more information about devices using Insight Management agents. To remove a plug-in from the assigned plug-in list, click on the "x" next to the plug-in name. To assign a plug-in, drag the plug-in name from available list to the assigned list. To see how our devices are affected, let's remove the zenoss.snmp.IpServiceMap and add zenoss.cmd.df. After we make the changes to the plug-ins for Coyote, scroll to the bottom of the page and click Save. Model Device Zenoss automatically models each device in our inventory every six hours, but we can manually force Zenoss to model the device. From the Device Status page, select Manage > Model Device from the page menu. Zenoss displays the results of the zenmodeler command in the window as shown in the following screenshot. Zenoss first determines which plugi-ns are available and then collects information based on those plug-ins. Notice that no cmd plug-ins are found, which means that the zenoss.cmd.df plug-in we added to Coyote will not be collected. After Zenoss models the device, we can review the device overview page to see what component types Zenoss discovered. IpService should not be listed. If we go back to the Collector Plug-ins page for Coyote, we can add the zenoss.snmp.IpService plug-in and then model the device again. Now, IpServices is displayed in the Component Type list as shown in the following screenshot. The Component Type list gets updated as part of the modeling process and so does the OS fields in the Device Information table (the greyed-out fields in the screen shot). If we enter values in these fields during the Add Device step, the values would be overwritten with the SNMP values. Our example made changes to the device level, which means that if we view the collector plug-ins for the /Server/Linux device class, the original plug-ins are specified. To view the plug-ins for the class: Select Devices from the navigation panel. Select Server from the sub-devices list. Select Linux from the sub-devices list. From the /Devices/Server/Linux page menu, select More > CollectorPlug-ins. Devices automatically inherit any changes we make to the class collector plug-ins the next time Zenoss models the devices. SSH Modeling If the monitored device does not support SNMP, or if we need to monitor a device behind a firewall, SSH provides an alternative to SNMP. Unlike SNMP, SSH needs the Zenoss Plug-ins installed on each monitored device and platform support is limited to Linux, Darwin, and FreeBSD. We also need to make sure that the monitored device has an SSH server installed so that the Zenoss system can log in and retrieve information. OpenSSH from openssh.com offers a good cross-platform SSH solution. The level of modeling provided by the Zenoss Plug-ins varies between platforms. For this reason, we may not achieve the same level of detail as we do with SNMP, but SSH modeling provides more detail than a port scan. To help us setup our SSH monitoring, Zenoss provides the /Server/Cmd class which is already configured with the command plug-ins we need to monitor via SSH. SSH Collector Plug-ins From the navigation panel, select Devices. Navigate to the /Server/Cmd class and click on the zProperties tab. Find the zCollectorPlug-ins field and click on the Edit link. A list of the assigned collector plug-ins is displayed as shown in the following screenshot. The important thing to note with the command collector plug-ins is the new level of specificity in the name. The zenoss.cmd.uname and zenoss.cmd.df plug-ins are common to all architectures, while the plug-ins with "linux" in the name work with Linux systems. Mac OS X platforms use the plug-ins with "darwin" in the name. If we did not have any any OS X systems to monitor, then we could remove allthe Darwin-based plug-ins from the /Server/Cmd class or, if we know that wedon't want to monitor the memory usage for any of our devices, we can removethat plug-in. We'll leave the collector plug-ins as they are for the /Server/Cmd class and change our test device Coyote to use SSH instead of SNMP. Zenoss Plug-ins Zenoss will monitor and retrieve some data using the SSH modeler even if we do not install the Zenoss plug-ins, but the device model will be incomplete. For example, file systems will be detected along with the size of each drive., but the usage statistics will not be reported. Zenoss also generates warning events if it cannot find the zenplugin.py command on the monitored system. The monitored system needs a Python environment installed. This can beinstalled using your distribution's package manager. If you have setuptoolsinstalled, you can install the Zenoss-Plug-ins package from the Cheese Shop (http://pypi.python.org/pypi/) with the following command as root: easy_install Zenoss-Plugins We can also build the Zenoss Plug-ins package from source: Download the Zenoss Plug-ins package from http://www.zenoss.com/download/. Extract the plug-in file. From the plug-in source directory, run the following commands as root: python setup.py build python setup.py install The setuptools procedure installs zenplugin.py to /usr/bin, which is important because we need to configure the device zProperties to look for the plug-ins in the correct location. To ensure that the plug-in file is working correctly, run the following command on the monitored device, which is Coyote in our example: zenplugin.py –list-plugins The command outputs the detected platform and the supported plug-ins as shown in the following screenshot.

Do you want to use paid incoming links? Paying for incoming links can be a tricky business if you do it the wrong way. Google doesn't like web sites that use this link building technique and their representative master anti-spam spokesman, Matt Cutts is very clear on this subject. Buy links and get penalized… sell links and get penalized as well The major penalty is a very likely drop in Page Rank. Although Page Rank is becoming less important as compared to your rankings on the search engine result pages, people still see it as a quality making if you do have a high Page Rank. Of course using AdWords to do a "Pay Per Click" campaign is also a form of paid links. If you want to use the sponsored link options to get your site started, that is fine, but the ultimate goal of this article is to get higher rankings in the organic results of the search engines. Studies support the idea of using sponsored links to bring in more traffic from the organic searchers even after the campaign has stopped. It depends on how hard you need the traffic to your site for business, or if you want to go for organic results. Helping people helps you with link building If you have a topic that you are passionate about and you build a web site about it, then this option is one for you. Find a forum that matches the topic of your web site and start helping other people with your knowledge. On most forums there is a possibility to have your own "Signature", where you can have one or more lines of text with a link that people can click on. For instance, the site http://forums.digitalpoint.com has a lot of requests for information on Joomla! where you can help people to solve their problems. After a number of replies to questions, you can put in your own signature such as:   The links you put in there will not only bring traffic from your posts, but they also count as incoming links for Google. Not all forums have the same rules—for example, some of them have a rule that you can put a link to your site, but it should be the URL only without your main keywords in the link. So, be sure to go to the best forums you can find on your topic and start helping others with your knowledge. In the meantime, work on your incoming links as well. Commenting done the right way Another option you have is to look for blogs about your web site's topic. You will already probably know the most useful ones in your field of expertise. Go to those blogs and read some of the posts they have published. If you are lucky, there will be some kind of widget that shows you how many readers they have on that blog for their RSS Feed or email system. Large numbers are a good sign as that means a lot of people will read the blog and it probably has a good ranking in Google. Read the posts that are relevant to your topic and if you can, write a comment which shows that you know more about the topic. Also, if possible, make a new suggestion or correct an error in the article. Don't write comments such as "I really liked this post", "Thank you for this information", or even "I really like your blog". If you write comments such as those you won't get any interaction with the blogger in question and you don't add value to the discussion. Such comments will get deleted or labeled as spam. When I get comment links such as these, I remove them as they add null to zero information for other visitors and they are clearly there just for link building. It won't work that way, and if you are outsourcing or want to outsource this kind of link building, here is a warning, make sure you state in your contract with these people that blog and comment spamming is not allowed! If you don't add that clause, they may start commenting in your name, linking to your site (well, you paid them to do that…) with the same remarks over and over again. What happens next is that bloggers will ban you from commenting on their blogs, and in the worst case scenario you will loose a lot of credibility in your community. People are sometimes better informed than you think and a mistake like the one mentioned above will cost you more than money alone. So, if you start commenting, ask yourself: Do I have something of value to add to the conversation? Will people read that comment? How effective will this blog be in sending me traffic? Keep those in mind, with more emphasis on the first point, and you will do fine. Finding places to comment As I said before, commenting is a great way to create your own incoming links. But how do you find more relevant blogs to read and comment on? First of all, do a search for blogs about your web site's topic. You can use http://blogsearch.google.com/ to find the most recent blog posts and see if the blogs it finds fit your web site's topic.   Technorati is of course the best place to look for blogs.   Go ahead and use the option search the blogosphere.... From the results of this initial search, you can filter based on several options. In the first selection list you will find options such as Search Posts, Search Blogs, Search Photos, and Seach Videos. The second selection list allows you to filter based on entire post or just tags. The third option is the one you really need to set and there you can choose to filter on a lot of authority.   This option means a lot of people are linking to that web site/blog and it will probably get lots of traffic and do well in the search engines. Those blogs are the ones you want your voice to be heard on and remember if you are going to comment, make sure it is a useful one. What you need to do after finding the blog, is to really check out the site. In some cases there might just be one post about your web site's topic on that blog. And you really want it to be on topic all the way!   Two other blog search services you can use are: http://www.icerocket.com http://www.blogpulse.com Both are set up to bring to you the most recent results like Google does but they have something extra. You can learn about trends as Icerocket has a trend tool and Blogpulse has its trend search option. Using those trend tools will give you more insight on which terms are "hot" at the moment and growing. If you combine that with the blogs you just found, for your keywords, you could have a winning team.

In this article by Kae Verens, we will look at: How to install and use the DataTables plugin How to load data pages on request from the server Searching and ordering the data From time to time, you will want to show data in your website and allow the data to be sorted and searched. It always impresses me that whenever I need to do anything with jQuery, there are usually plugins available, which are exactly or close to what I need. The DataTables plugin allows sorting, filtering, and pagination on your data. Here's an example screen from the project we will build in this article. The data is from a database of cities of the world, filtered to find out if there is any place called nowhere in the world: Get your copy of DataTables from http://www.datatables.net/, and extract it into the directory datatables, which is in the same directory as the jquery.min.js file. What the DataTables plugin does is take a large table, paginate it, and allow the columns to be ordered, and the cells to be filtered. Setting up DataTables Setting up DataTables involves setting up a table so that it has distinct < thead > and < tbody > sections, and then simply running dataTable() on it. As a reminder, tables in HTML have a header and a body. The HTML elements < thead > and < tbody > are optional according to the specifications, but the DataTables plugin requires that you put them in, so that it knows what to work with. These elements may not be familiar to you, as they are usually not necessary when you are writing your web pages and most people leave them out, but DataTables needs to know what area of the table to turn into a navigation bar, and which area will contain the data, so you need to include them. Client-side code The first example in this article is purely a client-side one. We will provide the data in the same page that is demonstrating the table. Copy the following code into a file in a new demo directory and name it tables.html: <html> <head> <script src="../jquery.min.js"></script> <script src="../datatables/media/js/jquery.dataTables.js"> </script> <style type="text/css"> @import "../datatables/media/css/demo_table.css";</style> <script> $(document).ready(function(){ $('#the_table').dataTable(); }); </script> </head> <body> <div style="width:500px"> <table id="the_table"> <thead> <tr> <th>Artist / Band</th><th>Album</th><th>Song</th> </tr> </thead> <tbody> <tr><td>Muse</td> <td>Absolution</td> <td>Sing for Absolution</td> </tr> <tr><td>Primus</td> <td>Sailing The Seas Of Cheese</td> <td>Tommy the Cat</td> </tr> <tr><td>Nine Inch Nails</td> <td>Pretty Hate Machine</td> <td>Something I Can Never Have</td> </tr> <tr><td>Horslips</td> <td>The Táin</td> <td>Dearg Doom</td> </tr> <tr><td>Muse</td> <td>Absolution</td> <td>Hysteria</td> </tr> <tr><td>Alice In Chains</td> <td>Dirt</td> <td>Rain When I Die</td> </tr> <!-- PLACE MORE SONGS HERE --> </tbody> </table> </div> </body> </html> When this is viewed in the browser, we immediately have a working data table: Note that the rows are in alphabetical order according to Artist/Band. DataTables automatically sorts your data initially based on the first column. The HTML provided has a < div > wrapper around the table, set to a fixed width. The reason for this is that the Search box at the top and the pagination buttons at the bottom are floated to the right, outside the HTML table. The < div > wrapper is provided to try to keep them at the same width as the table. There are 14 entries in the HTML, but only 10 of them are shown here. Clicking the arrow on the right side at the bottom-right pagination area loads up the next page: And finally, we also have the ability to sort by column and search all data: In this screenshot, we have the data filtered by the word horslips, and have ordered Song in descending order by clicking the header twice. With just this example, you can probably manage quite a few of your lower-bandwidth information tables. By this, I mean that you could run the DataTables plugin on complete tables of a few hundred rows. Beyond that, the bandwidth and memory usage would start affecting your reader's experience. In that case, it's time to go on to the next section and learn how to serve the data on demand using jQuery and Ajax. As an example of usage, a user list might reasonably be printed entirely to the page and then converted using the DataTable plugin because, for smaller sites, the user list might only be a few tens of rows and thus, serving it over Ajax may be overkill. It is more likely, though, that the kind of information that you would really want this applied to is part of a much larger data set, which is where the rest of the article comes in! Getting data from the server The rest of the article will build up a sample application, which is a search application for cities of the world. This example will need a database, and a large data set. I chose a list of city names and their spelling variants as my data set. You can get a list of this type online by searching. The exact point at which you decide a data set is large enough to require it to be converted to serve over Ajax, instead of being printed fully to the HTML source, depends on a few factors, which are mostly subjective. A quick test is: if you only ever need to read a few pages of the data, yet there are many pages in the source and the HTML is slow to load, then it's time to convert. The database I'm using in the example is MySQL (http://www.mysql.com/). It is trivial to convert the example to use any other database, such as PostgreSQL or SQLite. For your use, here is a short list of large data sets: http://wordlist.sourceforge.net/—Links to collections of words. http://www.gutenberg.org/wiki/Gutenberg:Offline_Catalogs—A list of books placed online by Project Gutenburg. http://www.world-gazetteer.com/wg.php?men=stdl—A list of all the cities in the world, including populations. The reason I chose a city name list is that I wanted to provide a realistic large example of when you would use this. In your own applications, you might also use the DataTables plugin to manage large lists of products, objects such as pages or images, and anything else that can be listed in tabular form and might be very large. The city list I found has over two million variants in it, so it is an extreme example of how to set up a searchable table. It's also a perfect example of why the Ajax capabilities of the DataTables project are important. Just to see the result, I exported all the entries into an HTML table, and the file size was 179 MB. Obviously, too large for a web page. So, let's find out how to break the information into chunks and load it only as needed. Client-side code On the client side, we do not need to provide placeholder data. Simply print out the table, leaving the < tbody > section blank, and let DataTables retrieve the data from the server. We're starting a new project here, so create a new directory in your demos section and save the following into it as tables.html: <html> <head> <script src="../jquery.min.js"></script> <script src="../datatables/media/js/jquery.dataTables.js"> </script> <style type="text/css"> @import "../datatables/media/css/demo_table.css"; table{width:100%} </style> <script> $(document).ready(function(){ $('#the_table').dataTable({ 'sAjaxSource':'get_data.php' }); }); </script> </head> <body> <div style="width:500px"> <table id="the_table"> <thead> <tr> <th>Country</th> <th>City</th> <th>Latitude</th> <th>Longitude</th> </tr> </thead> <tbody> </tbody> </table> </div> </body> </html> In this example, we've added a parameter to the .dataTable call, sAjaxSource, which is the URL of the script that will provide the data (the file will be named get_data.php). Server-side code On the server side, we will start off by providing the first ten rows from the database. DataTables expects the data to be returned as a two-dimensional array named aaData. In my own database, I've created a table like this: CREATE TABLE `cities` ( `ccode` char(2) DEFAULT NULL, `city` varchar(87) DEFAULT NULL, `longitude` float DEFAULT NULL, `latitude` float DEFAULT NULL, KEY `city` (`city`(5)) ) ENGINE=MyISAM DEFAULT CHARSET=utf8 Most of the searching will be done on city names, so I've indexed city. Initially, let's just extract the first page of information. Create a file called get_data.php and save it in the same directory as tables.html: <?php // { initialise variables $amt=10; $start=0; // } // { connect to database function dbRow($sql){ $q=mysql_query($sql); $r=mysql_fetch_array($q); return $r; } function dbAll($sql){ $q=mysql_query($sql); while($r=mysql_fetch_array($q))$rs[]=$r; return $rs; } mysql_connect('localhost','username','password'); mysql_select_db('phpandjquery'); // } // { count existing records $r=dbRow('select count(ccode) as c from cities'); $total_records=$r['c']; // } // { start displaying records echo '{"iTotalRecords":'.$total_records.', "iTotalDisplayRecords":'.$total_records.', "aaData":['; $rs=dbAll("select ccode,city,longitude,latitude from cities order by ccode,city limit $start,$amt"); $f=0; foreach($rs as $r){ if($f++) echo ','; echo '["',$r['ccode'],'", "',addslashes($r['city']),'", "',$r['longitude'],'", "',$r['latitude'],'"]'; } echo ']}'; // } In a nutshell, what happens is that the script counts how many cities are there in total, and then returns that count along with the first ten entries to the client browser using JSON as the transport.

Activity 3: Investigating texts using Quiz Aim: Using quiz to investigate texts Moodle modules: Quiz Extra programs: None Ease of setup: *** As noted elsewhere, Quiz can be a useful module for practicing different language skills. This is primarily because we can build in helpful feedback and because we can allow students to spend as much time as they want practicing. There are various ways that Quiz can help students listen. Here are some examples: Listening and matching: students listen for gist information and match answers to general questions about the text. Ordering task for arranging events in a sequence. Multiple-choice for information transfer, identifying speakers' attitudes, and identifying numbers. Gap-fill tasks: Students listen to a song, poem, or other text, and fill in the missing words. It's worth thinking carefully about what sorts of words you want to blank out. Do you want to focus on grammar words (prepositions, pronouns, and conjunctions, etc.), words that are difficult to spell, or keywords (words that convey the main meaning of the text)? To exemplify each of these examples, we'll make one quiz with four different question types. You could choose to have quizzes with any number of different question types. We'll take as our listening text a story which we recorded ourselves. We could record it in a recording program like Audacity. The story is about a rather special trip to the zoo. Here is a possible transcript abridged from http://www.onlyfunnystories.com/ZooJob.asp: One day an out of work mime artist is visiting the zoo and attempts to earn some money as a street performer monkey. As soon as he starts to draw a crowd, a zoo keeper grabs him and drags him into his office. The zoo keeper explains to the mime artist that the zoo's most popular attraction, a gorilla, has died suddenly and the keeper fears that attendance at the zoo will fall off. He offers the mime artist a job to dress up as the gorilla until they can get another one. The mime artist accepts. So the next morning the mime artist puts on the gorilla suit and enters the cage before the crowd comes. He discovers that it's a great job. He can sleep all he wants, play and make fun of people and he draws bigger crowds than he ever did as a mime. However, eventually the crowds tire of him and he tires of just swinging on trees. He begins to notice that the people are paying more attention to the lion in the cage next to his. Not wanting to lose the attention of his audience, he climbs to the top of his cage, crawls across a partition, and dangles from the top to the lion's cage. Of course, this makes the lion furious, but the crowd loves it. At the end of the day the zoo keeper comes and gives the mime artist a raise for being such a good attraction. Well, this goes on for some time, the mime keeps taunting the lion, the crowds grow larger, and his salary keeps going up. Then one terrible day when he is dangling over the furious lion he slips and falls. The mime artist is terrified. The lion gathers itself and prepares to pounce. The mime artist is so scared that he begins to run round and round the cage with the lion close behind. Finally, the mime artist starts screaming and yelling, "Help me, help me!", but the lion is quick and pounces. The mime artist soon finds himself flat on his back looking up at the angry lion and the lion says, "Shut up you idiot! Do you want to get us both fired?" The questions start with general gist questions (matching). Then comes an ordering question, which requires slightly more attention to detail. The last two are multiple-choice and gap-fill questions, which get students to focus on detailed aspects of the listening text. Here's how to do it The following sections refer you to the activities and point out any major differences. Setting up the quiz Listening and matching question Use NanoGong to create sound clips which replace pictures and texts. Here are some examples of the matching questions you could set up. These are general questions which help students get the gist of the story. Question Answer How many animals are there in the story?. Three Where does this take place? The zoo Where does the zoo keeper find the mime artist? On the street How many animals are there in the cages? Two This is what your matching question might look like: Here are a few more matching questions you could consider: Match recordings to pictures. Students could hear a description of an image (painting, photo) and identify the description. The easiest way to do this would be to take some photos of similar scenes. Match individual words to sounds. Students hear the recording and decide which words they are hearing. Recording Choice A. "I hear you're coming"   B."It's over here" hear/here   hear/here Ordering question In this variation students listen to a story and then order events in sequence. We need to make sure that the sequence is not guessable without hearing the story. Here are the stages from our story that you could include in the question: The zookeeper grabs the mime artist. The zookeeper offers the mime artist a job. The gorilla lies on top of the neighboring cage. The lion tries to attack the gorilla. The lion tells the gorilla off. This is what the ordering question would look like: Multiple-choice question Multiple-choice questions are a good way of getting students to investigate texts in more detail. Here are some possible questions we could include in this activity. Question 1 According to the story, why does the mime artist accept a job as a gorilla? Answer 1 His work on the street isn't going well. Answer 2 The zookeeper has an urgent need for a gorilla. Answer 3 He always wanted to work as a gorilla in a zoo. Answer 4 The last gorilla quit the job.

The basis for all of these topics is the object-oriented interface. Object-oriented versus MATLAB styles We have seen  a lot of examples, and in all of them we used the matplotlib.pyplot module to create and manipulate the plots, but this is not the only way to make use of the Matplotlib plotting power. There are three ways to use Matplotlib: pyplot: The module used so far in this article pylab:  A module to merge Matplotlib and NumPy together in an environment closer to MATLAB Object-oriented way: The Pythonic way to interface with Matplotlib Let's first elaborate a bit about the pyplot module: pyplot provides a MATLAB-style, procedural, state-machine interface to the underlying object-oriented library in Matplotlib. A state machine is a system with a global status, where each operation performed on the system changes its status. matplotlib.pyplot is stateful because the underlying engine keeps track of the current figure and plotting area information, and plotting functions change that information. To make it clearer, we did not use any object references during our plotting we just issued a pyplot command, and the changes appeared in the figure. At a higher level, matplotlib.pyplot is a collection of commands and functions that make Matplotlib behave like MATLAB (for plotting). This is really useful when doing interactive sessions, because we can issue a command and see the result immediately, but it has several drawbacks when we need something more such as low-level customization or application embedding. If we remember, Matplotlib started as an alternative to MATLAB, where we have at hand both numerical and plotting functions. A similar interface exists for Matplotlib, and its name is pylab. pylab (do you see the similarity in the names?) is a companion module, installed next to matplotlib that merges matplotlib.pyplot (for plotting) and numpy (for mathematical functions) modules in a single namespace to  provide an environment as near to MATLAB as possible, so that the transition would be easy. We and the authors of Matplotlib discourage the use of pylab, other than for proof-of-concept snippets. While being rather simple to use, it teaches developers the wrong way to use Matplotlib. The third way to use Matplotlib is through the object-oriented interface (OO, from now on). This is the most powerful way to write Matplotlib code because it allows for complete control of the result however it is also the most complex. This is the Pythonic way to use Matplotlib, and it's highly encouraged when programming with Matplotlib rather than working interactively. We will use it a lot from now on as it's needed to go down deep into Matplotlib. Please allow us to highlight again the preferred style that the author of this article, and the authors of Matplotlib want to enforce: a bit of pyplot will be used, in particular for convenience functions, and the remaining plotting code is either done with the OO style or with pyplot, with numpy explicitly imported and used for numerical functions. In this preferred style, the initial imports are: import matplotlib.pyplot as pltimport numpy as np In this way, we know exactly which module the function we use comes from (due to the module prefix), and it's exactly what we've always done in the code so far. Now, let's present the same piece of code expressed in the three possible forms which we just described. First, we present it in the style, pyplot only: In [1]: import matplotlib.pyplot as pltIn [2]: import numpy as npIn [3]: x = np.arange(0, 10, 0.1)In [4]: y = np.random.randn(len(x))In [5]: plt.plot(x, y)Out[5]: [<matplotlib.lines.Line2D object at 0x1fad810>]In [6]: plt.title('random numbers')In [7]: plt.show() The preceding code snippet results in: Now, let's see how we can do the same thing using the pylab interface: $ ipython -pylab... In [1]: x = arange(0, 10, 0.1)In [2]: y = randn(len(x)) In [3]: plot(x, y)Out[3]: [<matplotlib.lines.Line2D object at 0x4284dd0>] In [4]: title('random numbers')In [5]: show() Note that: ipython -pylab is not the same as running ipython and then: from pylab import * This is because ipython's-pylab switch, in addition to importing everything from pylab, also enables a specific ipython threading mode so that both the interactive interpreter and the plot window can be active at the same time. Finally, lets make the same chart by using OO style, but with some pyplot convenience functions: In [1]: import matplotlib.pyplot as pltIn [2]: import numpy as np In [3]: x = np.arange(0, 10, 0.1)In [4]: y = np.random.randn(len(x))In [5]: fig = plt.figure()In [6]: ax = fig.add_subplot(111)In [7]: l, = plt.plot(x, y)In [8]: t = ax.set_title('random numbers')In [9]: plt.show() The pylab code is the simplest, and ,pyplot is in the middle, while the OO is the most complex or verbose. As the Python Zen teaches us, "Explicit is better than implicit" and "Simple is better than complex" and those statements are particularly true for this example: for simple interactive sessions, pylab or ,pyplot are the perfect choice because they hide a lot of complexity, but if we need something more advanced, then the OO API makes clearer where things are coming from, and what's going on. This expressiveness will be appreciated when we will embed Matplotlib inside GUI applications. From now on, we will start presenting our code using the OO interface mixed with some pyplot functions. A brief introduction to Matplotlib objects Before we can go on in a productive way, we need to briefly introduce which Matplotlib objects compose a figure. Let's see from the higher levels to the lower ones how objects are nested: Object Description FigureCanvas Container class for the Figure instance Figure Container for one or more Axes instances Axes The rectangular areas to hold the basic elements, such as lines, text, and so on     Our first (simple) example of OO Matplotlib In the previous pieces of code, we had transformed this: ...In [5]: plt.plot(x, y)Out[5]: [<matplotlib.lines.Line2D object at 0x1fad810>]... into: ...In [7]: l, = plt.plot(x, y)... The new code uses an explicit reference, allowing a lot more customizations. As we can see in the first piece of code, the plot() function returns a list of Line2D instances, one for each line (in this case, there is only one), so in the second code, l is a reference to the line object, so every operation allowed on Line2D can be done using l. For example, we can set the line color with: l.set_color('red') Instead of using the keyword argument to plot(), so the line information can be changed after the plot() call. Subplots In the previous section, we have seen a couple of important functions without introducing them. Let's have a look at them now: fig = plt.figure(): This function returns a Figure, where we can add one or more Axes instances. ax = fig.add_subplot(111): This function returns an Axes instance, where we can plot (as done so far), and this is also the reason why we call the variable referring to that instance ax (from Axes). This is a common way to add an Axes to a Figure, but add_subplot() does a bit more: it adds a subplot. So far we have only seen a Figure with one Axes instance, so only one area where we can draw, but Matplotlib allows more than one. add_subplot() takes three parameters: fig.add_subplot(numrows, numcols, fignum) where: numrows  represents the number of rows of subplots to prepare numcols  represents the number of columns of subplots to prepare fignum  varies from 1 to numrows*numcols and specifies the current subplot (the one used now) Basically, we describe a matrix of numrows*numcols subplots that we want into the Figure; please note that fignum is 1 at the upper-left corner of the Figure and it's equal to numrows*numcols at the bottom-right corner. The following table should provide a visual explanation of this:   numrows=2, numcols=2, fignum=1 numrows=2, numcols=2, fignum=2 numrows=2, numcols=2, fignum=3 numrows=2, numcols=2, fignum=4

The big picture: Who are users? Users are people who have registered their details with you and are allocated access to certain resources and information, depending on their role within the scope of your website. They can be administrators and content editors/contributors or customers who purchase goods and services from you. This is different to a casual visitor who lands up at the frontend of your site because he/she has your website address or hopefully has found you through a search engine. You may be able to turn these casual visitors into registered users if you have something to offer them. Say you want to provide special content to only those who are genuinely interested in your services or products. Encouraging them to register allows you to collect contact information (it's best to ask only for the most relevant details, as people generally don't want to give out more than they need to) and keep in touch. Hopefully, you can convert it into an ongoing relationship with sales and benefits for your business. Generating interest in your products and services is important here and suggesting some level of exclusivity can make your customers feel privileged in terms of being privy to information not readily available to just anyone. Put simply though, users are your website visitors, content contributors, and administrators. Depending on their role, they are essentially divided into two broad groups with smaller sub-categories within them. Frontend users Frontend users do not have access to the administration interface and can only access material and information through the frontend. They can be: Registered users, authors, editors, and publishers who have privileges to edit and update information. Guests or casual visitors to your site. These visitors come to your site anonymously and unregistered. People who register their details in order to transact with you. Frontend user definitions When a user is registered with you, they are allocated to a group, as per the settings applied within the Global Configuration. They can be any one of the following: Registered Users are visitors to your site who have registered themselves in order to view certain content or transact with you. Authors can submit new content articles to the site with approval, but can't edit existing articles. A publisher or someone higher must approve these submissions. Editors can submit and edit new content articles. A publisher or someone higher must also approve these entries. Publishers  can submit new content articles, edit existing articles, and publish the articles. None of these user groups have access to the administration interface, and can only edit or add material from the frontend. Administration users Administration users can edit and update the content of your site by logging into the administration control panel and are those who: Have Administrator Manager or Super Administrator access. Each of these roles has specific access. For example, the Manager profile does not have access to the User Manager section. Have various levels of access within the administration control panel, the highest level being Super Administrator. Editing the frontend Login Form From the frontend of your website, the Login Form allows users to access content that is potentially specialized and only visible to them, or to transact with you if you're running an e-commerce site. You can also customize your Login Form by adding text and a link to create new accounts. Lost usernames and passwords The Forgot your password and Forgot your username links are important not only for users to fi nd their password or username again, but also to help you to manage users. Rather than unnecessarily creating a new account if they have lost their login details, having an e-mail prompt sent to reset their details is a more efficient approach. Clicking the link for either will generate a request to enter an e-mail address. A confi rmation e-mail will be sent with a verification token or string of characters which allows the user to enter and reset their password. Alternatively, their username will be emailed to them.      

Embedding a progress bar in a status bar This topic explains how to embed a progress bar in a panel's status bar, a scenario found in countless user interfaces: How to do it Create a click handler that will simulate a long-running activity and update the progress bar: Ext.onReady(function() { var loadFn = function(btn, statusBar) { btn = Ext.getCmp(btn); btn.disable(); Ext.fly('statusTxt').update('Saving...'); pBar.wait({ interval: 200, duration: 5000, increment: 15, fn: function() { btn.enable(); Ext.fly('statusTxt').update('Done'); } });}; Create an instance of the progress bar: var pBar = new Ext.ProgressBar({ id: 'pBar', width: 100}); Create a host panel and embed the progress bar in the bbar of the panel. Also, add a button that will start the progress bar updates: var pnl = new Ext.Panel({ title: 'Status bar with progress bar', renderTo: 'pnl1', width: 400, height: 200, bodyStyle: 'padding:10px;', items: [{ xtype: 'button', id: 'btn', text: 'Save', width:'75', handler: loadFn.createCallback('btn', 'sBar') }], bbar: { id: 'sBar', items: [{ xtype: 'tbtext', text: '',id:'statusTxt' },'->', pBar] }}); How it works The first step consists of creating loadFn, a function that simulates a long-running operation, so that we can see the progress bar animation when the button is clicked. The heart of loadFn is a call to ProgressBar.wait(…), which initiates the progress bar in an auto-update mode. And this is how the status bar is embedded in the bbar of the panel: bbar: { id: 'sBar', items: [{ xtype: 'tbtext', text: '',id:'statusTxt' },'->', pBar] Observe how the progress bar is sent to the rightmost location in the status bar with the help of a Toolbar.Fill instance, declared with '->'. Creating a custom look for the status bar items Customizing the look of toolbar items is relatively simple. In this recipe, you will learn how to create toolbar items with a sunken look that can be found in many desktop applications: How to do it Create the styles that will provide the custom look of the status bar text items: .custom-status-text-panel{ border-top:1px solid #99BBE8; border-right:1px solid #fff; border-bottom:1px solid #fff; border-left:1px solid #99BBE8; padding:1px 2px 2px 1px;} Create a host panel: Ext.onReady(function() { var pnl = new Ext.Panel({ title: 'Status bar with sunken text items', renderTo: 'pnl1', width: 400, height: 200, bodyStyle: 'padding:10px;', Define the panel's bbar with the text items: bbar: { id: 'sBar', items: [ { id: 'cachedCount', xtype:'tbtext', text: 'Cached: 15' }, ' ', { id: 'uploadedCount', xtype: 'tbtext', text: 'Uploaded: 7' }, ' ', { id: 'invalidCount', xtype: 'tbtext', text: 'Invalid: 2' } ]}, Now, add a handler for the afterrender event and use it to modify the styles of the text items: listeners: { 'afterrender': { fn: function() { Ext.fly(Ext.getCmp('cachedCount').getEl()).parent(). addClass('custom-status-text-panel'); Ext.fly(Ext.getCmp('uploadedCount').getEl()).parent(). addClass('custom-status-text-panel'); Ext.fly(Ext.getCmp('invalidCount').getEl()).parent(). addClass('custom-status-text-panel'); }, delay:500 }} How it works The actual look of the items is defined by the style in the custom-status-text-panel CSS class. After the host panel and toolbar are created and rendered, the look of the items is changed by applying the style to each of the TD elements that contain the items. For example: Ext.fly(Ext.getCmp('uploadedCount').getEl()).parent(). addClass('custom-status-text-panel'); See also... The previous recipe, Embedding a progress bar in a status bar, explains how a progress bar can be embedded in a panel's status bar Using a progress bar to indicate that your application is busy In this topic, you will learn how to use a progress bar to indicate that your application is busy performing an operation. The next screenshot shows a progress bar built using this recipe: How to do it Define the progress bar: Ext.onReady(function() { Ext.QuickTips.init(); var pBar = new Ext.ProgressBar({ id: 'pBar', width: 300, renderTo: 'pBarDiv'}); Add a handler for the update event and use it to update the wait message: pBar.on('update', function(val) { //Handle this event if you need to // execute code at each progress interval. Ext.fly('pBarText').dom.innerHTML += '.';}); Create a click handler for the button that will simulate a long-running activity: var btn = Ext.get('btn');btn.on('click', function() { Ext.fly('pBarText').update('Please wait'); btn.dom.disabled = true; pBar.wait({ interval: 200, duration: 5000, increment: 15, fn: function() { btn.dom.disabled = false; Ext.fly('pBarText').update('Done'); } });}); Add the button to the page: <button id="btn">Start long-running operation</button> How it works After creating the progress bar, the handler for its update event is created. While I use this handler simply to update the text message, you can use it to execute some other code every time that a progress interval occurs. The click handler for the button calls the progress bar's wait(…) function, which causes the progress bar to auto-update at the configured interval and reset itself after the configured duration: pBar.wait({ interval: 200, duration: 5000, increment: 15, fn: function() { btn.dom.disabled = false; Ext.fly('pBarText').update('Done'); }}); There's more The progress bar can also be configured to run indefinitely by not passing the duration config option. Clearing the progress bar in this scenario requires a call to the reset() function. See also... The next recipe, Using a progress bar to report progress updates, illustrates how a progress bar can be set up to notify the user that progress is being made in the execution of an operation The Changing the look of a progress bar recipe (covered later in this article) shows you how easy it is to change the look of the progress bar using custom styles Summary This article consisted recipes that examined the commonly-used menu items, as well as the different ways of setting up toolbars and progress bars in your applications. [ 1 | 2 ] If you have read this article you may be interested to view :   Making Progress with Menus and Toolbars using Ext JS 3.0: Part 1 Load, Validate, and Submit Forms using Ext JS 3.0: Part 1 Load, Validate, and Submit Forms using Ext JS 3.0: Part 2 Load, Validate, and Submit Forms using Ext JS 3.0: Part 3

Plotting dates Sooner or later, we all have had the need to plot some information over time, be it for the bank account balance each month, the total web site accesses for each day of the year, or one of many other reasons. Matplotlib has a plotting function ad hoc for dates, plot_date() that considers data on X, Y, or both axes, as dates, labeling the axis accordingly. As usual, we now present an example, and we will discuss it later: In [1]: import matplotlib as mplIn [2]: import matplotlib.pyplot as pltIn [3]: import numpy as npIn [4]: import datetime as dtIn [5]: dates = [dt.datetime.today() + dt.timedelta(days=i) ...: for i in range(10)]In [6]: values = np.random.rand(len(dates))In [7]: plt.plot_date(mpl.dates.date2num(dates), values, linestyle='-');In [8]: plt.show() First, a note about linestyle keyword argument: without it, there's no line connecting the markers that are displayed alone. We  created  the dates array using timedelta(), a datetime function that helps us define a date interval—10 days in this case. Note how we had to convert our date values using the date2num() function. This is because Matplotlib represents dates as float values corresponding to the number of days since 0001-01-01 UTC. Also note how the X-axis labels, the ones that have data values, are badly rendered. Matplotlib provides ways to address the previous two points—date formatting and conversion, and axes formatting. Date formatting Commonly, in Python programs, dates are represented as datetime objects, so we have to first convert other data values into datetime objects, sometimes by using the dateutil companion module, for example: import datetimedate = datetime.datetime(2009, 03, 28, 11, 34, 59, 12345) or import dateutil.parserdatestrings = ['2008-07-18 14:36:53.494013','2008-07-20 14:37:01.508990', '2008-07-28 14:49:26.183256']dates = [dateutil.parser.parse(s) for s in datestrings] Once we have the datetime objects, in order to let Matplotlib use them, we have to convert them into floating point numbers that represent the number of days since 0001-01-01 00:00:00 UTC. To do that, Matplotlib itself provides several helper functions contained in the matplotlib.dates module: date2num():  This function converts one or a sequence of datetime objects to float values representing days since 0001-01-01 00:00:00 UTC (the fractional parts represent hours, minutes, and seconds) num2date():  This function converts one or a sequence of float values representing days since 0001-01-01 00:00:00 UTC to datetime objects (or a sequence, if the input is a sequence) drange(dstart, dend, delta): This function returns a date range (a sequence) of float values in Matplotlib date format; dstart and dend are datetime objects while delta is a datetime.timedelta instance Usually, what we will end up doing is converting a sequence of datetime objects into a Matplotlib representation, such as: dates = list of datetime objectsmpl_dates = matplotlib.dates.date2num(dates) drange() can be useful in situations like this one: import matplotlib as mplfrom matplotlib import datesimport datetime as dtdate1 = dt.datetime(2008, 9, 23)date2 = dt.datetime(2009, 4, 12)delta = dt.timedelta(days=10)dates = mpl.dates.drange(date1, date2, delta) where dates will be a sequence of floats starting from date1 and ending at date2 with a delta timestamp between each item of the list. Axes formatting with axes tick locators and formatters As we have already seen, the X labels on the first image are not that nice looking. We would expect Matplotlib to allow a better way to label the axis, and indeed, there is. The solution is to change the two parts that form the axis   ticks—locators and formatters. Locators control the tick's position, while formatters control the formatting of labels. Both have a major and minor mode: the major locator and formatter are active by default and are the ones we commonly see, while minor mode can be turned on by passing a relative locator or formatter function (because minors are turned off by default by assigning NullLocator and NullFormatter to them). While this is a general tuning operation and can be applied to all Matplotlib plots, there are some specific locators and formatters for date plotting, provided by matplotlib.dates: MinuteLocator, HourLocator,DayLocator, WeekdayLocator,MonthLocator, YearLocator are all the  locators available that place a tick at the time specified by the name, for example, DayLocator will draw a tick at each day. Of course, a minimum knowledge of the date interval that we are about to draw is needed to select the best locator. DateFormatter is the tick formatter that uses strftime() to format strings.   The default locator and formatter are matplotlib.ticker.AutoDateLocator and matplotlib.ticker.AutoDateFormatter, respectively. Both are set by the plot_date() function when called. So, if you wish to set a different locator and/or formatter, then we suggest to do that after the plot_date() call in order to avoid the plot_date() function resetting them to the default values. Let's group all this up in an example: In [1]: import matplotlib as mplIn [2]: import matplotlib.pyplot as pltIn [3]: import numpy as npIn [4]: import datetime as dtIn [5]: fig = plt.figure()In [6]: ax2 = fig.add_subplot(212)In [7]: date2_1 = dt.datetime(2008, 9, 23)In [8]: date2_2 = dt.datetime(2008, 10, 3)In [9]: delta2 = dt.timedelta(days=1)In [10]: dates2 = mpl.dates.drange(date2_1, date2_2, delta2)In [11]: y2 = np.random.rand(len(dates2))In [12]: ax2.plot_date(dates2, y2, linestyle='-');In [13]: dateFmt = mpl.dates.DateFormatter('%Y-%m-%d')In [14]: ax2.xaxis.set_major_formatter(dateFmt)In [15]: daysLoc = mpl.dates.DayLocator()In [16]: hoursLoc = mpl.dates.HourLocator(interval=6)In [17]: ax2.xaxis.set_major_locator(daysLoc)In [18]: ax2.xaxis.set_minor_locator(hoursLoc)In [19]: fig.autofmt_xdate(bottom=0.18) # adjust for date labels displayIn [20]: fig.subplots_adjust(left=0.18)In [21]: ax1 = fig.add_subplot(211)In [22]: date1_1 = dt.datetime(2008, 9, 23)In [23]: date1_2 = dt.datetime(2009, 2, 16)In [24]: delta1 = dt.timedelta(days=10)In [25]: dates1 = mpl.dates.drange(date1_1, date1_2, delta1)In [26]: y1 = np.random.rand(len(dates1))In [27]: ax1.plot_date(dates1, y1, linestyle='-');In [28]: monthsLoc = mpl.dates.MonthLocator()In [29]: weeksLoc = mpl.dates.WeekdayLocator()In [30]: ax1.xaxis.set_major_locator(monthsLoc)In [31]: ax1.xaxis.set_minor_locator(weeksLoc)In [32]: monthsFmt = mpl.dates.DateFormatter('%b')In [33]: ax1.xaxis.set_major_formatter(monthsFmt)In [34]: plt.show() The result of executing the previous code snippet is as shown: We drew the subplots in reverse order to avoid some minor overlapping problems. fig.autofmt_xdate() is used to nicely format date tick labels. In particular, this function rotates the labels (by using rotation keyword argument, with a default value of 30°) and gives them  more room (by using bottom keyword argument, with a default value of 0.2). We can achieve the same result, at least for the additional spacing, with: fig = plt.figure()fig.subplots_adjust(bottom=0.2)ax = fig.add_subplot(111) This can also be done by creating the Axes instance directly with: ax = fig.add_axes([left, bottom, width, height]) while specifying the explicit dimensions. The subplots_adjust() function allows us to control the spacing around the subplots by using the following keyword arguments: bottom, top, left, right: Controls the spacing at the bottom, top, left, and right of the subplot(s)     wspace, hspace: Controls the horizontal and vertical spacing between subplots We can also control the spacing by using these parameters in the Matplotlib configuration file: figure.subplot.<position> = <value> Custom formatters and locators Even if it's not strictly related to date plotting, tick formatters allow for custom formatters too: ...import matplotlib.ticker as ticker...def format_func(x, pos): return <a transformation on x>...formatter = ticker.FuncFormatter(format_func)ax.xaxis.set_major_formatter(formatter)... The  function format_func will be called for each label to draw, passing its value and position on the axis. With those two arguments, we can apply a transformation (for example, divide x by 10) and then return a value that will be used to actually draw the tick label. Here's a general note on NullLocator: it can be used to remove axis ticks by simply issuing: ax.xaxis.set_major_locator(matplotlib.ticker.NullLocator()) Text properties, fonts, and LaTeX Matplotlib has excellent text support, including mathematical expressions, TrueType font support for raster and vector outputs, newline separated text with arbitrary rotations, and Unicode. We have total control over every text property (font size, font weight, text location, color, and so on) with sensible defaults set in the rc configuration file. Specifically for those interested in mathematical or scientific figures, Matplotlib implements a large number of TeX math symbols and commands to support mathematical expressions anywhere in the figure. We already saw some text functions, but the following list contains all the functions which can be used to insert text with the pyplot interface, presented along with the corresponding API method and a description: Pyplot function API method Description text() mpl.axes.Axes.text() Adds text at an arbitrary location to the Axes xlabel() mpl.axes.Axes.set_xlabel() Adds an axis label to the X-axis ylabel() mpl.axes.Axes.set_ylabel() Adds an axis label to the Y-axis title() mpl.axes.Axes.set_title() Adds a title to the Axes figtext() mpl.figure.Figure.text() Adds text at an arbitrary location to the Figure suptitle() mpl.figure.Figure.suptitle() Adds a centered title to the Figure annotate() mpl.axes.Axes.annotate() Adds an annotation with an optional arrow to the Axes     All of these commands return a matplotlib.text.Text instance. We can customize the text properties by passing keyword arguments to the functions or by using matplotlib.artist.setp(): t = plt.xlabel('some text', fontsize=16, color='green') We can do it as: t = plt.xlabel('some text')plt.setp(t, fontsize=16, color='green') Handling objects allows for several new possibilities; such as setting the same property to all the objects in a specific group. Matplotlib has several convenience functions to return the objects of a plot. Let's take the example of the tick labels: ax.get_xticklabels() This line of code returns a sequence of object instances (the labels for the X-axis ticks) that we can tune: for t in ax.get_xticklabels(): t.set_fontsize(5.) or else, still using setp(): setp(ax.get_xticklabels(), fontsize=5.) It can take a sequence of objects, and apply the same property to all of them. To recap, all of the properties such as color, fontsize, position, rotation, and so on, can be set either: At function call using keyword arguments Using setp() referencing the Text instance Using the modification function Fonts Where there is text, there are also fonts to draw it. Matplotlib allows for several font customizations. The most complete documentation on this is currently available in the Matplotlib configuration file, /etc/matplotlibrc. We are now reporting that information here. There are six font properties available for modification. Property name Values and description font.family It has five values: serif (example, Times) sans-serif (example, Helvetica) cursive (example, Zapf-Chancery) fantasy (example, Western) monospace (example, Courier) Each of these font families has a default list of font names in decreasing order of priority associated with them (next table). In addition to these generic font names, font.family may also be an explicit name of a font available on the system. font.style Three values: normal (or roman), italic, or oblique. The oblique style will be used for italic, if it is not present. font.variant Two values: normal or small-caps. For TrueType fonts, which are scalable fonts, small-caps is equivalent to using a font size of smaller, or about 83% of the current font size. font.weight Effectively has 13 values-normal, bold, bolder, lighter, 100, 200, 300, ..., 900. normal is the same as 400, and bold is 700. bolder and lighter are relative values with respect to the current weight. font.stretch 11 values-ultra-condensed, extra-condensed, condensed, semi-condensed, normal, semi-expanded, expanded, extra-expanded, ultra-expanded, wider, and narrower. This property is not currently implemented. It works if the font supports it, but only few do. font.size The default font size for text, given in points. 12pt is the standard value.

There are many reasons why you would want to display a calendar. You can use it to display upcoming events, to keep a diary, or to show a timetable. Recently, for example, I combined a calendar with an online store for a client to book meetings and receive payments more intuitively. Google calendar is probably what springs to mind when people think of calendars online. There is a very good plugin called jquery-week-calendar that shows a week with events in a fashion similar to Google's calendar. Its homepage is at http://www.redredred.com.au/projects/jquery-week-calendar/. To get the latest copy of the plugin, go to http://code.google.com/p/jquery-week-calendar/downloads/list and get the highest-numbered file. The examples in this article are done with version 1.2.0. Download the library and extract it so that there is a directory named jquery-weekcalendar-1.2.0 in the root of your demo directory. Displaying the calendar As usual, the HTML for the simplest configuration is very simple. Save this as calendar.html: <html> <head> <script src="../jquery.min.js"></script> <script src="../jquery-ui.min.js"></script> <script src="../jquery-weekcalendar-1.2.0/jquery.weekcalendar.js"> </script> <script src="calendar.js"></script> <link rel="stylesheet" type="text/css" href="../jquery-ui.css" /> <link rel="stylesheet" type="text/css" href="../jquery-weekcalendar-1.2.0/jquery.weekcalendar.css"/> </head> <body> <div id="calendar_wrapper" style="height:500px"></div> </body> </html> We will keep all of our JavaScript in an external file called calendar.js, which will initially contain just this: $(document).ready(function() { $('#calendar_wrapper').weekCalendar({ 'height':function($calendar){ return $('#calendar_wrapper')[0].offsetHeight; } }); }); This is fairly straightforward. The script will apply the widget to the #calendar_wrapper element, and the widget's height will be set to that of the wrapper element. Even with this tiny bit of code, we already have a good-looking calendar, and when you drag your mouse cursor around it, you'll see that events are created as you lift the mouse up: It looks good, but it doesn't do anything yet. The events are temporary, and will vanish as soon as you change the week or reload the page. In order to make them permanent, we need to send details of the events to the server and save them there. Creating an event What we need to do is to have the client save the event on the server when it is created. In this article, we'll use PHP sessions to save the data for the sake of simplicity. Sessions are chunks of data, which are kept on the server side and are related to the cookie or PHPSESSID parameter that the client uses to access that session. We will use sessions in these examples because they do not need as much setup as databases. For your own projects, you should adapt the PHP side in order to connect to a database instead. If you are using this article to create a full application, you will obviously want to use something more permanent than sessions, in which case the PHP code should be adapted such that all references to sessions are replaced with database references instead. This is beyond the scope of this book, but as you are a PHP developer, you probably do this everyday anyway! When the event has been created, we want a modal dialog to appear and ask for more details. In this test case, we'll add a text area for further details, which allows for more data than would appear in the small visible area in the calendar itself. A modal dialog is a "pop up" that appears and blocks all other actions on the page until it has been taken care of. It's useful in cases where the answer to a question must be known before a script can carry on with its work. Now, let's create an event and add it to our calendar. Client-side code In the calendar.js file, add an eventNew event to the weekCalendar call: $(document).ready(function() { $('#calendar_wrapper').weekCalendar({ 'height':function($calendar){ return $('#calendar_wrapper')[0].offsetHeight; }, 'eventNew':function(calEvent, $event) { calendar_new_entry(calEvent,$event); } }); }); When an event is created, the calendar_new_entry function will be called with details of the new event in the calEvent parameter. Now, add the function calendar_new_entry: function calendar_new_entry(calEvent,$event){ var ds=calEvent.start, df=calEvent.end; $('<div id="calendar_new_entry_form" title="New Calendar Entry"> event name<br /> <input value="new event" id="calendar_new_entry_form_title" /> <br /> body text<br /> <textarea style="width:400px;height:200px" id="calendar_new_entry_form_body">event description </textarea> </div>').appendTo($('body')); $("#calendar_new_entry_form").dialog({ bgiframe: true, autoOpen: false, height: 440, width: 450, modal: true, buttons: { 'Save': function() { var $this=$(this); $.getJSON('./calendar.php?action=save&id=0&start=' +ds.getTime()/1000+'&end='+df.getTime()/1000, { 'body':$('#calendar_new_entry_form_body').val(), 'title':$('#calendar_new_entry_form_title').val() }, function(ret){ $this.dialog('close'); $('#calendar_wrapper').weekCalendar('refresh'); $("#calendar_new_entry_form").remove(); } ); }, Cancel: function() { $event.remove(); $(this).dialog('close'); $("#calendar_new_entry_form").remove(); } }, close: function() { $('#calendar').weekCalendar('removeUnsavedEvents'); $("#calendar_new_entry_form").remove(); } }); $("#calendar_new_entry_form").dialog('open'); } What's happening here is that a form is created and added to the body (the second line of the function), then the third line of the function creates a modal window from that form and adds some buttons to it. Our modal dialog should look like this: The Save button, when pressed, calls the server-side file calendar.php with the parameters needed to save the event, including the start and end, and the title and body. When the result returns, the calendar is refreshed with the new event's data included. When any of the buttons are clicked, we close the dialog and remove it from the page completely. Note how we are sending time information to the server (shown highlighted in the code we just saw). JavaScript time functions usually measure in milliseconds, but we want to send it to PHP, which generally measures time in seconds. So, we convert the value on the client so that the PHP can use the received data as it is, without needing to do anything to it. Every little helps! Server-side code On the server side, we want to take the new event and save it. Remember that we're doing it in sessions in this example, but you should feel free to adapt this to any other model that you wish. Create a file called calendar.php and save it with this source in it: <?php session_start(); if(!isset($_SESSION['calendar'])){ $_SESSION['calendar']=array( 'ids'=>0, ); } if(isset($_REQUEST['action'])){ switch($_REQUEST['action']){ case 'save': // { $start_date=(int)$_REQUEST['start']; $data=array( 'title'=>(isset($_REQUEST['title'])?$_REQUEST['title']:''), 'body' =>(isset($_REQUEST['body'])?$_REQUEST['body']:''), 'start'=>date('c',$start_date), 'end' =>date('c',(int)$_REQUEST['end']) ); $id=(int)$_REQUEST['id']; if($id && isset($_SESSION['calendar'][$id])){ $_SESSION['calendar'][$id]=$data; } else{ $id= ++$_SESSION['calendar']['ids']; $_SESSION['calendar'][$id]=$data; } echo 1; exit; // } } } ?> In the server-side code of this project, all the requested actions are handled by a switch statement. This is done for demonstration purposes—whenever we add a new action, we simply add a new switch case. If you are using this for your own purposes, you may wish to rewrite it using functions instead of large switch cases. The date function is used to convert the start and end parameters into ISO 8601 date format. That's the format jquery-week-calendar prefers, so we'll try to keep everything in that format. Visually, nothing appears to happen, but the data is actually being saved. To see what's being saved, create a new file named test.php, and use the var_dump function in it to examine the session data (view it in your browser): <?php session_start(); var_dump($_SESSION); ?> Here's an example from my test machine:

eZ Webin For this article it is assumed that the eZ Webin package is installed as a frontend for our site. This package is very flexible and is usually used as a starting point for developing a new site. By default, it includes: A flexible layout Some useful custom content classes (blog, event, forum, article, and so on) Web 2.0 features, such as a tag cloud and comment functions Custom template operators In our project, we will extend and override the eZ Webin template in order to create the Packtmedia Magazine site and add some features needed for the project. We will see this step-by-step as we understand better how eZ Publish works. Overriding the standard page layout The page layout is the main template and defines the style of the entire site. To create a page layout template, we need to create a file named pagelayout.tpl and place it inside the templates folder of our design extension. As we said, we will work with eZ Webin. This extension doesn't use the standard page layout but overrides the standard page layout with its own custom behavior. We need to do the same overriding from the eZ Webin pagelayout.tpl. To override the template, we have to copy it in our design's extension folder placed in extension/packtmedia/design/magazine/templates/. Now open a shell and execute this: # cd /var/www/packtmediaproject/extension# cp /ezwebin/design/ezwebin/templates/pagelayout.tpl /packtmedia/design/magazine/templates/ We will use this new pagelayout.tpl file to implement the wireframe that we developed in the previous sections. Section for our project eZ Publish includes features for creating a particular view in order to add content objects inside specified sections. For example, if we take a look at our wireframe, we need to assign a different layout for rendering the Issue archive folder and its subfolders. To do this, we have to create a new section in the administration panel and associate it to the entire Issue archive subtree. After that, we can use the fetch functions to select the correct view for that section. Creating a new section To create a new section, we have to open our browser and from the site's backend, select the Setup tab from the top menu. We then need to navigate to the Sections link in the left-hand menu, and then click on the New section button. Next, we will create a new section called Archive and select the default Content structure value in the select menu. Now, a new Archive link will appear in the Sections list. We have to click on the + button to the left of the Archive link, and then select the Issue archive node, by selecting the relevant checkbox. After we have saved, click on the Select button. All of the Issue archive subfolders will be placed inside the Archive section. We have to remember the ID of this section, which we'll use to create the override rules. In this case, the section ID number is 6, as seen in the first screenshot in the Creating a new section section. Setting up the section permission access By default, eZ Publish creates private sections that only an administrator can access. To make a section public, we need to give read permission to anonymous users. To set up the rules, we have to go back to Setup tab on the top menu, and then click on the Role and policies link on the left-hand menu. Here, we have to click on the Edit button on the right-hand side of the Anonymous link, and then click on the New policy button. Next, select the content option in the Module field, and then click on the Grant access to one function button. Select the read option in the Function field, and then click on the Grant limited access button. Next, select the Anonymous option for the Section field. Click on the OK button, and then click on the OK button on the Edit <Anonymous> Role page. Now, the anonymous user can access the Archive section. In the next paragraph, we will use this section to create custom override rules. Customizing the page layout After we copy the pagelayout.tpl template into the new path, we have to work on it in order to create the three columns inside the content layout of the eZ Webin template. To do this, first of all, we have to remove the leftmost sidebar, along with the secondary navigation menu, inside the Archive section that we have created. Open the pagelayout.tpl file that you have copied into your favorite IDE, and take a look at the code. At line 62 we will find the following code: {if and( is_set( $content_info.class_identifier ), ezini('MenuSettings', 'HideLeftMenuClasses', 'menu.ini' )|contains($content_info.class_identifier ) )}{set $pagestyle = 'nosidemenu noextrainfo'} Here, eZ Webin hides the side menu if the content class belongs to the array returned by the ezini operator. We now need to extend the IF sentence and add a control to the section ID, by using the following code: {if or(and( is_set( $content_info.class_identifier ), ezini('MenuSettings', 'HideLeftMenuClasses', 'menu.ini' )|contains($content_info.class_identifier ) ), $module_result.section_id|eq(6))}{set $pagestyle = 'nosidemenu noextrainfo'} As we can see, this code will now check to see if the browsed section has an ID equal to 6 (that is, the archive section ID that we previously created) and if it has, will hide the unnecessary sidebar. CSS editing Luckily, the entire template code of eZ Webin is strongly semantic and all of the elements have their own IDs and classes. Thanks to this, we can change a lot of things by simply working on the CSS. By default, the CMS uses six CSSes. These are: core.css: this is the global stylesheet where all of the standard tag styles for eZ Publish are defined; usually, this file is overridden by all of the others webstyletoolbar.css: this stylesheet is imported for the frontend web toolbar that is used for editing the content pagelayout.css: this is where all of the default styles of the global pagelayout are defined content.css: this is where all the default styles of the content classes are defined site-colors.css: this file is used to override the pagelayout.css to skin a site differently classes-colors.css: this file is used to override the default styles defined by the content.css file To edit the CSS, we have to copy the original eZ Webin stylesheet from the /var/www/packtmediaproject/extension/ezwebin/design/ezwebin/stylesheets folder to our design directory and then to execute the following commands: # cd /var/www/packtmediaproject/extension/# cp -rf ezwebin/design/ezwebin/stylesheets/* packtmedia/design/magazine/stylesheets/ Now, every time that we want to change the stylesheet, we have to remember to edit the CSS files in the design/magazine/stylesheets/ directory of our extension. Creating a new style package In eZ Publish, as we did for extension, it's possible to create a portable style package, so we can share and reuse our custom style in other sites. We can do this by navigating to the backend admin site and uploading the new stylesheet that we want to use. First, we have to create our CSS files by using our favorite CSS editor; we have to remember that they will override the default styles, so we only need to add the lines that we want to change. After we create the new stylesheet files, we have to open the browser, click on the Setup tab, and then click on the Package link in the left-hand sidebar. The system will ask us where we want to create our new package. We will select the local repository and click on the Create new package button. eZ Publish will then ask us which kind of package we want to create. We have to select the Site style wizard, and then click on the Create new package button. We can now choose a thumbnail for the style that we are uploading, or continue without it. After selecting the thumbnail, the wizard will ask us to choose the CSS file that we previously created. Select it, and then click on the Next button. With the wizard, we will also upload one or more images, for example a new logo file, or other images related to the CSS. To not upload files, we simply have to click on the Next button without selecting a file in the form. We have to remember that all of the images that we upload will be saved in a subfolder named images, which will be placed in the same directory as the stylesheet. This will be useful when we need to set the relative path of the images used inside the CSS. We can now add the package information and export it to our PC (if required). The new style package will automatically be installed in the eZ Publish package folder. It will be accessible from the Design tab, via the sidebar's Look and Feel link. If we select the package and clear the cache automatically, it will be applied to the frontend. Summary In this article, we learned the basics of the templating system of eZ Publish. We worked on template's function and operator, and also learned how to extend the default WYSIWYG editor of eZ Publish. Moreover, we created the site wireframe and learned how the design overriding feature works. We also created a new stylesheet package, and applied it to our extension.

eZ Publish templating In the first part of this article, we will introduce the basics of the eZ Publish templating system, which will help us to better understand the rest of the article Templating eZ Publish has its own templating system based on the decoupling of layout and content. This will help us to assign a custom layout to any content object in different sections. Moreover, just as other templating platforms, such as Smarty (http://www.smarty.net), eZ Publish has its own markup to help developers with control structure operations, subtemplating, and on-the-fly content editing. It also exposes a particular function to fetch and filter content from a database. The official eZ Publish website has a constant, up-to-date reference with the entire templating markup. We suggest you to use the following link every time that you need to know more details about the available arguments:http://ez.no/doc/ez_publish/technical_manual/4_0/templates/ The templating markup All of the eZ Publish templating code should be placed between curly brackets. When the CMS will parse our template file and find the curly brackets, it will start executing the related code. Escaping the curly bracketsIf we need to use curly brackets, for example to write a javascript function inside our template, we need to use the {literal} operator. {literal}<script type="text/javascript">function alertMe() { window.alert('Harkonen approaching!');}</script>{/literal} Control structure operators We can divide these function into two main families: Conditional (IF-THEN-ELSE) Looping (FOR-FOREACH-WHILE) Whereas the first one should be used to change the template behavior according to some predefined condition, the other one will help us to seek and manage array and content structures. Conditional control Conditional control is sometimes useful for changing the output when some data is received by the system. For example, we would need a different CSS class for a particular value, or to change the <div> class, if the current month is the same as the one displayed, as shown below: {def $current_month=currentdate()|datetime(custom, '%F')}{if $node.name|eq($current_month) }<span class="this-month">{else}<span class="default-month">{/if}{undef $current_month} In the first line, we define a $current_month variable that has a value of the name of the month (for example, October), retrieved by the datetime() operator. Then we use the IF conditional control to choose the correct class. In the last line, we delete the variable previously created, by releasing it from system memory. Loop control As stated above, the loop control structure can be used to iterate through an array. We can, for example, create an unordered list (<ul>) from an array of items. <ul>{foreach $items as $item} <li>{node_view_gui content_node=$item view=line}</li>{/foreach}</ul> This will be rendered as: <ul> <li>1st item</li> <li>2nd item</li> <li>3rd item</li> ...</ul> As you can see, the FOREACH structure is similar to the PHP structure. In this example, the most interesting line is the definition of the list object. This we can literally read as: render the content node (node_view_gui) from a specific node (content_node=$issue) using the line view template (view=line). Fetch functions With the fetch functions, we can retrieve all of the information about a content object for a module. The fetch functions can also be used to create custom queries to retrieve only the information we need, and not everything. eZ Publish exposes many fetch functions, which can be read about on the documentation site at http://ez.no/doc/ez_publish/technical_manual/4_0/reference/template_fetch_functions The most important, and most used, fetch functions are those regarding the content, sections, and user modules. For example, we can fetch the root content object by using the following code in our template: {$object = fetch('content', 'object', hash('id', '1'))} We can then use the $object variable to display the object inside the HTML code. Generic template functions and operators The CMS gives us a lot of functions and operators, all of them described in the reference manual of the eZ System documentation site. As a thumb rule, we should remember that to execute a particular function, we have to use the following syntax: {function_name parameter1=value1 ... parameterN=valueN } All parameters are separated by spaces and can be specified in no particular order. If we want to manage the operators, we have to remember that they accept the parameters passed in a specific order, separated by a comma. Moreover, an operator should handle a parameter passed to it with a pipe (|). {$piped_parameter|my_operator( parameter1, ..., parameterN ) } Every time we see a pipe after a variable, we have to remember that we are passing a value to an operator. We used the datetime() operator in the previous example for the conditional control functionality. As a reference to API functions and operators, you can use the official variable documentation that is constantly updated on the eZ System site:http://ez.no/doc/ez_publish/technical_manual/4_0/reference/template_operatorshttp://ez.no/doc/ez_publish/technical_manual/4_0/reference/template_functions Layout variables By default, the page layout template can access some of the variables passed by the CMS. These variables, named Layout variables, can be used to render system and user information, or to change the output. These variables are automatically configured by eZ Publish when it analyzes and executes the code related to a view. One of the most important variables is $module_result, which contains the results generated by the module and the view that is being executed. A module is an HTTP interface that interacts with eZ Publish. A module consists of a set of views that contain the code to be executed. For example, if we call the following URL, the system executes the login view code of the user module:http://www.example.com/index.php/user/login. As an API reference, you can use the official variable documentation that is constantly updated on the eZ System site:http://ez.no/doc/ez_publish/technical_manual/4_0/templates/the_pagelayout/variables_in_pagelayout Overriding a template eZ Publish offers a set of standard templates that are useful, but they cannot cover all the possible design needs. To solve this issue, the CMF provides a fallback system that allows us to load different templates based on specific rules. This system is usually referred to as overriding, and allows us to change the template for each module's view by overriding the default template when the user is in a particular context. Embedding HTML inside the WYSIWYG XML editor, pt.2 We have to override a standard behavior of eZ Publish to create a generic HTML block inside the WYSIWYG XML editor. We use a content style named html for the online editor and we will work on it for the frontend to render it correctly. First, we have to create a file named literal.tpl and place it in the design folder of our extension. The following code will do exactly what we need: # mkdir -p /var/www/packtmediaproject/extension/packtmedia/design/magazine/templates/datatype/view/ezxmltags/# cd /var/www/packtmediaproject/extension/packtmedia/design/magazine/templates/datatype/view/ezxmltags/# touch literal.tpl Next, we will open the literal.tpl file in our preferred IDE. Now we will add the code that will, by default, render everything surrounded by a <pre> tag and the raw HTML code, if the class is html: {if ne( $classification, 'html' )} <pre {if ne( $classification|trim, '' )} class="{$classification|wash}"{/if}>{$content|wash( xhtml )}</pre>{else} {$content}{/if} This code will check to see if the $classification variable is different from the "html" string in order to add the <pre> tag and then, again, it will add a class attribute to the <pre> tag if the $classification variable is not null. To use it, we only need to reset the cache from the shell prompt by using the following command: cd /var/www/packmediaproject/php bin/php/ezcache.php --clear-all --purge The ezcache.php file is a PHP shell script that can be used to clear and manage the eZ Publish cache. This file has many parameters, which can be viewed by using the --help parameter. Creating a new design Before starting work on the eZ Webin template code, we need to create a wireframe in order to decide on the layout structure. We will use this structure to override the standard layout files. A wireframe is a basic visual guide that is used in web design to suggest the structure of a website and the relationships between its pages. Wireframe editorsThere are a lot of commercial and free wireframe editors. To create our site's wireframes, we will use the Firefox plugin called Pencil(http://www.evolus.vn/Pencil/).We have chosen Pencil because it is open source and works on every platform that runs the Firefox browser.If you need something more complete, you should take a look at Balsamiq (http://www.balsamiq.com/) or at OmniGraffle (http://www.omnigroup.com/applications/OmniGraffle/) if you have an Apple computer. Our site will have at least six different page layouts: The homepage The issue page, where we will display the cover and the articles list The issue archive page, by month and by years The staff profile page, where we will display the latest articles that the editor has written, along with his profile The article and the forum pages, with the default layout based on the eZ Webin design Now we will illustrate the first four layouts because we will work on them, overriding their standard eZ Webin layout. The homepage Starting from the homepage, we can see that the site will have, in the top-left corner, a logo for the magazine and a place-holder for a banner. Under these, we will have the main navigation menu and the main content area. We have chosen a three-column layout in order to easily manage the content that we want to show. In the homepage, the first column will show the latest news and the middle column will show the information and cover of the latest issue. The last column will have two boxes—one with the most important article from the latest issue and the other with the forum thread. Issue page The issue page will show some information of a specific magazine issue. In this page, the middle box of the homepage will shift towards the left, and in the right column there will be the highlighted article for the issue. At the bottom of the page, we will find all of the other articles. The issue archive We have to remember that our magazine is released monthly, so we need an archive page where we can collect all of the past issues. The issue archive page, which can be reached by clicking on the main navigation menu, will again show some information from the latest issue. (We need to sell our articles!) The rightmost column of the template will show all of the covers for the current or selected year. At the bottom of the page, we will create a box with links to the past issues grouped by years and months. The staff profile page The staff profile page will display information from a staff profile, such as his avatar, biography, and the latest articles that he has written. The staff profile page will have three columns. The first column will show information regarding the editor's profile, the middle column will show all of the articles the editor has written (paged five by five) and the third will be used for banners or other images. >> Continue Reading: Creating a Design with eZ Publish 4 Templating System: Part 2