How-To Tutorials

SAC at a Glance Point your Browser to the URL of your Scalix server, following this syntax: http:///sac. A pop-up window with the Administration Console Login is opened. If you are using Firefox or another browser with pop-up suppression, perhaps the configuration will need some corrections. Allow the Scalix server to open popups. In Firefox, you can easily configure this by clicking in the yellow bar on top of the displayed page. Other browsers may require editing the preferences. Otherwise, Scalix will provide a web page for you with a link, which opens the Admin Console in the same browser window. Logging In On Scalix 11, the Scalix Administration Login looks like this: Enter the Administrator's name in the field Login ID, exactly as configured during installation. Activate the reminder that you are connected via http and not through https by clicking on option field Not using a secure https connection. Once we have configured https for Scalix, the login dialog will not provide this option anymore. However, enabling https is not that easy, and therefore not standard in Scalix, except for the installations on Red Hat Enterprise. Click on the button Login to start the Administration console. A First Look Around The Scalix Administration Console is a Web application provided by a Tomcat application server. The only requirement for it is a modern browser supporting JavaScript. Firefox and Internet Explorer do fine, Konqueror may work soon. The Admin Console window is split in three parts: A menu with icons called Toolbar A list view on the lower left named Contents Pane and The main window on the right, called Display Pane The icons in the menu bar let you choose the administration task you want to accomplish, the content pane lists the possible entries that can be edited, and the options and parameters of a selected entry are presented in the display pane. By clicking on one of the icons on the Toolbar, you can access the different sections of the Scalix Administration Console. The first three sections are about users, groups, and resources, and will be used in daily administration for adding, deleting or modifying these objects. The section Plugins offers a management GUI for your own or third-party Scalix plug-ins. The Server Info icon leads to a concise list of running services, where the administrator can set the log level of these services and browse through the services' log files. The Settings Icon allows you to set preferences for the server and new users. A concise online help is available, and the icons Refresh and Logout complete the menu bar's icons. Navigating in the Admin Console A nice gadget in SAC is the little icon on the top left of the main window. Surrounded by four arrows, this icon displays the icon of the current section and enables the administrator to navigate in a quick and easy manner through the administration console. Clicking the up or down arrows will select and activate the next entry upwards or downwards in the list view to the left, and the left/right arrows navigate you back and forth in a browser-like fashion. Users, Groups, Resources... Now click on the Users icon in order to switch to the user management dialog. Click on the entry of the only user present at this time, sxadmin. For every user, there are six tabs where the user information is stored. The tab General holds the most important information: Username, Display Name, and Email address. This information is all that is necessary to add an user and use the new account. The other tabs contain contact information, group memberships, and administrative delegations. The mailbox quota, that is the amount of storage that the user's account may sum up to, is configured in the Mail dialog. On the Advanced tab, the administrator can add a role to the user, decide whether this user is a Standard or a Premium User, and give him a different authentication ID. Changing Passwords There are other features in the Admin Console that you will be using frequently once you are master of some Scalix users. One of them is probably the button Change Password on the lower right corner leading directly to the password dialog. This button is present in every user's configuration dialog.

MySQL Workbench is a visual database design tool recently released by MySQL AB. The tool is specifically for designing MySQL database. What you build in MySQL Workbench is called physical data model. A physical data model is a data model for a specific RDBMS product; the model in this article will have some MySQL unique specifications. We can generate (forward-engineer) the database objects from its physical model, which in addition to tables and their columns, can also include other objects such as view. MySQL Workbench has many functions and features; this article by Djoni Darmawikarta shows some of them by way of an example. We’ll build a physical data model for an order system where an order can be a sale order or a purchase order; and then, forward-engineer our model into an MySQL database. The physical model of our example in EER diagram will look like in the following MySQL Workbench screenshot. Creating ORDER Schema Let’s first create a schema where we want to store our order physical model. Click the + button (circled in red). Change the new schema’s default name to ORDER. Notice that when you’re typing in the schema name, its tab name on the Physical Schemata also changes accordingly—a nice feature. The order schema is added to the Catalog (I circled the order schema and its objects in red). Close the schema window. Confirm to rename the schema when prompted. Creating Order Tables We’ll now create three tables that model the order: ORDER table and its two subtype tables: SALES_ORDER and PURCHASE_ORDER, in the ORDER schema. First of all, make sure you select the ORDER schema tab, so that the tables we’ll create will be in this schema. We’ll create our tables as EER diagram (EER = Enhanced Entity Relationship). So, double-click the Add Diagram button. Select (click) the Table icon, and then move your mouse onto the EER Diagram canvas and click on the location you want to place the first table. Repeat for the other two tables. You can move around the tables by dragging and dropping. Next, we’ll work on table1, which we’ll do so using the Workbench’s table editor. We start the table editor by right-clicking the table1 and selecting Edit Table. Next, we’ll work on table1, which we’ll do so using the Workbench’s table editor. We start the table editor by right-clicking the table1 and selecting Edit Table. Rename the table by typing in ORDER over table1. We’ll next add its columns, so select the Columns tab. Replace idORDER column name with ORDER_NO. Select INT as the data type from the drop-down list. We’d like this ORDER_NO column to be valued incrementally by MySQL database, so we specify it as AI column (Auto Increment). AI is a specific feature of MySQL database. You can also specify other physical attributes of the table, such as its Collation; as well as other advanced options, such as its trigger and partioning (the Trigger and Partioning tabs). Notice that on the diagram our table1 has changed to ORDER, and it has its first column, ORDER_NO. In the Catalog you can also see the three tables. The black dots on the right of the tables indicate that they’ve been included in an diagram.  

Considering the different approaches Though there are different approaches that can be taken to serve content in multiple formats, the best solution will be specific to your circumstances and implementation. Almost any approach you take will have maintenance overhead. You'll have multiple places to update when things change. As copies of your template files proliferate, a simple text change can become a large task. Some of the cases we'll look at don't require much consideration. Serving a printable version of a page, for example, is straightforward and easily accomplished. Putting a pumpkin in your site header at Halloween or using a heart background around Valentine's Day can make your site seem timely and relevant, especially if you are in a seasonal business. Other techniques, such as serving different templates to different browsers, devices, or user-agents might create serious debate among content authors. Since serving content to mobile devices is becoming a new standard of doing business, we'll make it the focus of this article. Serving mobile devices The Mobile Web will remind some old timers (like me!) of the early days of web design where we'd create different sites for Netscape and Internet Explorer. Hopefully, we take lessons from those days as we go forward and don't repeat our mistakes. Though we're not as apt to serve wholly different templates to different desktop browsers as we once were, the mobile device arena creates special challenges that require careful attention. One way to serve both desktop and mobile devices is a one-size-fits-all approach. Through carefully structured and semantically correct XHTML markup and CSS selectors identified to be applied to handheld output, you can do a reasonable job of making your content fit a variety of contexts and devices. However, this method has a couple of serious shortcomings. First, it does not take into account the limitations of devices for rich media presentation with Flash, JavaScript, DHTML, and AJAX as they are largely unsupported on all but the highest-end devices. If your site depends on any of these technologies, your users can get frustrated when trying to experience it on a mobile device. Also, it doesn't address the varying levels of CSS support by different mobile devices. What looks perfect on one device might look passable on another and completely unusable on a third because only some of the CSS rules were applied properly. It also does not take into account the potentially high bandwidth costs for large markup files and CSS for users who pay by the amount of data transferred. For example, putting display: none on an image doesn't stop a mobile device from downloading the file. It only prevents it from being shown. Finally, this approach doesn't tailor the experience to the user's circumstances. Users tend to be goal-oriented and have specific actions in mind when using the mobile web, and content designers should recognize that simply recreating the desktop experience on a smaller screen might not solve their needs. Limiting the information to what a mobile user is looking for and designing a simplified navigation can provide a better user experience. Adapting content You know your users best, and it is up to you to decide the best way to serve them. You may decide to pass on the one-size-fits-all approach and serve a separate mobile experience through content adaptation. The W3C's Mobile Web Initiative best practices guidelines suggest giving users the flexibility and freedom to choose their experience, and provide links between the desktop and mobile templates so that they can navigate between the two. It is generally not recommended to automatically redirect users on mobile devices to a mobile site unless you give them a way to access the full site. The dark side to this kind of content adaptation is that you will have a second set of template files to keep updated when you make site changes. It can also cause your visitors to search through different bookmarks to find the content they have saved. Before we get into multiple sites, let's start with some examples of showing alternative templates on our current site. Setting up our example Since we want to customize the output of our detail page based on the presence of a variable in the URL, we're going to use a view function instead of a generic view. Let us consider a press release application for a company website. The press release object will have a title, body, published date, and author name.In the root directory of your project (in the directory projects/mycompany), create the press application by using the startapp command: $ python manage.py startapp press This will create a press folder in your site. Edit the mycompany/press/models.py file: from django.db import models class PressRelease(models.Model): title = models.CharField(max_length=100) body = models.TextField() pub_date = models.DateTimeField() author = models.CharField(max_length=100) def __unicode__(self): return self.title Create a file called admin.py in the mycompany/press directory, adding these lines: from django.contrib import adminfrom mycompany.press.models import PressRelease admin.site.register(PressRelease) Add the press and admin applications to your INSTALLED_APPS variable in the settings.py file: INSTALLED_APPS = ( 'django.contrib.auth', 'django.contrib.admin', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'mycompany.press',) In the root directory of your project, run the syncdb command to add the new models to the database: $ python manage.py syncdb We will be prompted to create a superuser, go ahead and create it. We can access the admin site by browsing to http://localhost:8000/admin/ and add data. Create your mycompany/press/urls.py file as shown: urlpatterns = patterns('', (r'detail/(?P<pid>d+)/$', 'mycompany.press.views.detail'), (r'list/$','django.views.generic.list_detail.object_list', press_list_dict), (r'latest/$','mycompany.press.views.latest'), (r'$','django.views.generic.simple.redirect_to', {'url': '/press/list/'})) In your mycompany/press/views.py file, your detail view should look like this: from django.http import HttpResponsefrom django.shortcuts import get_object_or_404from django.template import loader, Contextfrom mycompany.press.models import PressRelease def detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=pid) t = loader.get_template('press/detail.html') c = Context({'press': p}) return HttpResponse(t.render(c)) Let's jazz up our template a little more for the press release detail by adding some CSS to it. In mycompany/templates/press/detail.html, edit the file to look like this: <html><head><title>{{ press.title }}</title><style type="text/css">body { text-align: center;}#container { margin: 0 auto; width: 70%; text-align: left;}.header { background-color: #000; color: #fff;}</style></head><body><div id="container"><div class="header"><h1>MyCompany Press Releases</h1></div><div><h2>{{ press.title }}</h2><p>Author: {{ press.author }}<br/>Date: {{ press.pub_date }}<br/></p><p>{{ press.body }}</p></div></body></html> Start your development server and point your browser to the URL http://localhost:8000/press/detail/1/. You should see something like this, depending on what data you entered before when you created your press release: If your press release detail page is serving correctly, you're ready to continue. Remember that generic views can save us development time, but sometimes you'll need to use a regular view because you're doing something in a way that requires a view function customized to the task at hand. The exercise we're about to do is one of those circumstances, and after going through the exercise, you'll have a better idea of when to use one type of view over another. Serving printable pages One of the easiest approaches we will look at is serving an alternative version of a page based on the presence of a variable in the URL (aka a URL parameter). To serve a printable version of an article, for example, we can add ?printable to the end of the URL. To make it work, we'll add an extra step in our view to check the URL for this variable. If it exists, we'll load up a printer-friendly template file. If it doesn't exist, we'll load the normal template file. Start by adding the highlighted lines to the detail function in the mycompany/press/views.py file: def detail(request, pid): ''' Accepts a press release ID and returns the detail page ''' p = get_object_or_404(PressRelease, id=pid) if request.GET.has_key('printable'): template_file = 'press/detail_printable.html' else: template_file = 'press/detail.html' t = loader.get_template(template_file) c = Context({'press': p}) return HttpResponse(t.render(c)) We're looking at the request.GET object to see if a query string parameter of printable was present in the current request. If it was, we load the press/detail_printable.html file. If not, we load the press/detail.html file. We've also changed the loader.get_template function to look for the template_file variable. To test our changes, we'll need to create a simple version of our template that only has minimal formatting. Create a new file called detail_printable.html in the mycompany/templates/press/ directory and add these lines into it: <html><head><title>{{ press.title }}</title></head><body><h1>{{ press.title }}</h1><p>Author: {{ press.author }}<br/>Date: {{ press.pub_date }}<br/></p><p>{{ press.body }}</p></body></html> Now that we have both regular and printable templates, let's test our view.Point your browser to the URL http://localhost:8000/press/detail/1/, and you should see our original template as it was before. Change the URL to http://localhost:8000/press/detail/1/?printable and you should see our new printable template: Creating site themes Depending on the audience and focus of your site, you may want to temporarily change the look of your site for a season or holiday such as Halloween or Valentine's Day. This is easily accomplished by leveraging the power of the TEMPLATE_DIRS configuration setting. The TEMPLATE_DIRS variable in the settings.py file allows you to specify the location of the templates for your site. Also TEMPLATE_DIRS allows you to specify multiple locations for your template files. When you specify multiple paths for your template files, Django will look for a requested template file in the first path, and if it doesn't find it, it will keep searching through the remaining paths until the file is located. We can use this to our advantage by adding an override directory as the first element of the TEMPLATE_DIRS value. When we want to override a template with a special themed one, we'll add the file to the override directory. The next time the template loader tries to load the template, it will find it in the override directory and serve it. For example, let's say we want to override our press release page from the previous example. Recall that the view loaded the template like this (from mycompany/press/views.py): template_file = 'press/detail.html't = loader.get_template(template_file) When the template engine loads the press/detail.html template file, it gets itfrom the mycompany/templates/ directory as specified in the mycompany/settings.py file: TEMPLATE_DIRS = ( '/projects/mycompany/templates/',) If we add an additional directory to our TEMPLATE_DIRS setting, Django will look in the new directory first: TEMPLATE_DIRS = ( '/projects/mycompany/templates/override/’, '/projects/mycompany/templates/',) Now when the template is loaded, it will first check for the file /projects/mycompany/templates/override/press/detail.html. If that file doesn't exist, it will go on to the next directory and look for the file in /projects/mycompany/templates/press/detail.html. If you're using Windows, use the Windows-style file path c:/projects/mycompany/templates/ for these examples. Therein lies the beauty. If we want to override our press release template, we simply drop an alternative version with the same file name into the override directory. When we're done using it, we just remove it from the override directory and the original version will be served (or rename the file in the override directory to something other than detail.html). If you're concerned about the performance overhead of having a nearly empty override directory that is constantly checked for the existence of template files, we should consider caching techniques as a potential solution for this. Testing the template overrides Let's create a template override to test the concept we just learned. In your mycompany/settings.py file, edit the TEMPLATE_DIRS setting to look like this: TEMPLATE_DIRS = ( '/projects/mycompany/templates/override/', '/projects/mycompany/templates/',) Create a directory called override at mycompany/templates/ and another directory underneath that called press. You should now have these directories: /projects/mycompany/templates/override//projects/mycompany/templates/override/press/ Create a new file called detail.html in mycompany/templates/override/press/ and add these lines to the file: <html><head><title>{{ press.title }}</title></head><body><h1>Happy Holidays</h1><h2>{{ press.title }}</h2><p>Author: {{ press.author }}<br/>Date: {{ press.pub_date }}<br/></p><p>{{ press.body }}</p></body></html> You'll probably notice that this is just our printable detail template with an extra "Happy Holidays" line added to the top of it. Point your browser to the URL http://localhost:8000/press/detail/1/ and you should see something like this: By creating a new press release detail template and dropping it in the override directory, we caused Django to automatically pick up the new template and serve it without us having to change the view. To change it back, you can simply remove the file from the override directory (or rename it). One other thing to notice is that if you add ?printable to the end of the URL, it still serves the printable version of the file we created earlier. Delete the mycompany/templates/override/ directory and any files in it as we won't need them again.

The code used in this article can be downloaded from here. Plugin composition and operation     Like a module, in its simplest form, a plugin can consist of only two files, a PHP file with the actual code for the plugin, and an XML manifest that tells Joomla! what to do with the plugin. Despite this apparent simplicity, plugins are very powerful, and more difficult to understand than modules and components. Plugins are designed to run at certain times during the execution of our site, and they perform actions that can only be done at these times. For example, in our sample site we want to hide some of our content from guests, and only show it to paid subscribers. This action can only be performed when we are actually preparing the content to be displayed, because we need to wait until we identify if the viewer is a guest or subscriber, and then make the changes to the content dynamically. In a different example, checking if a subscriber's subscription is valid is something that only needs to be done when they try to login, and not on every page load. Plugin types Plugins are divided into eight types, as follows: Authentication Content Editors Editors-XTD Search System User XML-RPC Authentication Authentication plugins are designed to allow the site to check the user's authentication against a variety of sources. The default is to check the user's authentication against a username and password stored in the Joomla! database, which, as of Joomla! 1.5, will be the username and password fields in the #__user table (#__ is the table prefix we chose when setting up Joomla!). However, any source with a public API can be used to verify someone's authentication details. Common uses are LDAP, OpenID, a Google account, a subscription, community component, and more. On our site, for example, we are already using an authentication plugin to verify the subscriptions of users when they attempt to login. Content Possibly the most commonly used of all plugins, content plugins allow content items to be modified or have additional features added to them. We could, for example, use content plugins to cloak email addresses, embed audio or video into our pages, or do text replacements. We can even embed components and modules into our pages via plugins. We will later look at a content plugin that we will use to hide and show content depending on a user's subscription. Editors Editors plugins add WYSIWYG editors that we can use when editing our content. We installed JCE on our site earlier, which is the most popular Joomla! editor plugin as of this publication according to Joomla.org. Editors-XTD Editors-XTD (extended) plugins allow us to add additional buttons to the editors. The Image, Read more, and Pagebreak buttons on the default Joomla! WYSIWYG editor, for example, are actually plugins. Search Search plugins allow us to search through the data from different components. By default, Joomla! comes with plugins that search through content articles and the Contacts and Weblinks components. These can be expanded upon by creating or installing search plugins for other extensions. System System plugins are arguably the most powerful and most flexible types of plugins for Joomla!, as they can execute at several different pre-defined points during the execution of a Joomla! page plugin. They can be used to perform a vast array of functions, such as loading extra scripts or CSS into the header of a web page, redirecting people away from pages, logging statistics, and more. User User plugins allow us to perform actions at different times with respect to users. Such times include logging in and out, and also when saving changes to a user's profile. User plugins are often used to create a "bridge" between Joomla! and other web applications (such as the phpBB forum or the osCommerce e-commerce platform.). XML-RPC XML-RPC plugins are for communicating between our Joomla! site and other external applications, such as a desktop application or a different web site. Plugin events As a Joomla! site loads a page, it steps through a series of events as part of that process. The events it steps through are determined by the type of page it is loading. Plugins are always tied to one or more of these events, and are executed during those events as required. When loading a page of content, for example, we would step through a mix of the system and some of the content events. When loading the same page for editing, we will step through the system events, different content events, and also possibly editor events. The events triggered in Joomla! are: Authentication onAuthenticate Content onPrepareContent onAfterDisplayTitle onBeforeDisplayContent onBeforeContentSave onAfterContentSave Editors onInit onGetContent onSetContent onSave onDisplay onGetInsertMethod Editors XTD (Extended) onDisplay Search onSearch onSearchAreas System onAfterInitialise onAfterRoute onAfterDispatch onAfterRender User onLoginUsexr onLoginFailure onLogoutUser onLogoutFailure onBeforeStoreUser onAfterStoreUser onBeforeDeleteUser onAfterDeleteUser XML-RPC onGetWebServices Most of these events are easy to understand from their name, but just in case, more information can be found on the Joomla! documentation wiki at http://docs.joomla.org/CategoryPlugins. Some events are only activated at specific times, such as onAuthenticate, which is only activated when someone logs into their account. Others are activated on every page load. Content events are activated on all content pages and only on content pages, not on pages with components other than com_content. Content plugins are also only executed on the main body content itself and don't have access to the template or other module data. So a text replacement content plugin, for example, wouldn't change any text in modules or the template, only in the main content itself. It is actually possible for modules and components to manually activate plugin events with clever programming, but this is not the default Joomla! behavior. It is usually done when a developer wants to apply content plugin restrictions/changes to a module. Plugin order Aside from the events and types, there is a third important factor to consider when setting up our plugins. That is the order in which the plugins of a particular type are executed. This order is best observed on the Plugin Manager screen that can be found under the Extensions menu. The order in which the plugins execute is something not many people think about, but is really quite powerful and useful. This is because the plugins which execute later, can then use the output or effects of the earlier executing plugins as input. For example, imagine we have a plugin that displays different text for different user types, and we have another plugin that reads certain text values and replaces them with embedded video or audio. If we wanted to be able to show different videos to different groups, then we could use the first plugin to generate the different command strings for the second plugin, and have it generate them based on the user type. The second plugin, our media embedding plugin, doesn't even know that the first plugin exists. All it knows is which videos it needs to display based on what is in the content item. If the media plugin executes first, then it will generate both videos regardless of the user type. As another example, imagine we have some sort of external application and we log users into it after they authenticate via an authentication plugin. We need to make sure that this plugin is executed after all of our other authentication plugins that may check a user's credentials or account status. Otherwise, someone may get logged into our external application even though they were prevented from login into our Joomla! site. So a hacker, for example, could get access to our external application without needing to even successfully get into our main site. This was all because we had the order of our plugins wrong. So when we install and activate plugins, it is well worth taking the time to double check that everything happens in the order it is meant to be in. If one of our plugins is not behaving how it should, it might be worth checking the order to see if another plugin is conflicting with it. Customizing a Plugin Now that we have a better understanding of how our plugins work and fit together, we are going to try our hand at customizing one for our site. This will hopefully give us the understanding and confidence to make any other customizations we need in the future. As with modules, it is often easier to find a plugin that does most of what we want it to do and then make changes to it so that it meets our needs more completely. Looking back over our goals, one that requires a plugin is that we want to limit access to certain parts of our content to only our paying subscribers. This effect is going to be best achieved via content plugin, so we chose the Ninja Access plugin to fill this need. To use Ninja Access we first need to mark the content we want to restrict with special tags and indicate the user groups we want to see what is contained within the tags. When the page is produced, the plugin reads the visitor's user group and then compares it to the ones in the list provided by the tag. If the user groups match, then the content is displayed, if not, then it is hidden. For example: {njaccess 0}shows only to guest users{/njaccess}{njaccess 18,19,20,21,23,24,25}shows to all users who are not a guest{/njaccess} The numbers in the examples above indicate the default Joomla! user group ids. The most important ones are: 0 = Guests 18 = Registered 24 = Administrators 25 = Super Administrators We could use this as it is, but as we don't have a component installed to create new access groups, it won't be very flexible. We could get into trouble in the future if we decide to let people register without getting a subscription, or create a free subscription. In this instance, we will have paying and free subscribers all in the number 18 user group. Also, as we are always going to be restricting the same groups, we don't really need to type the parameters in every single time. Making our plugins always restrict the same groups automatically will save us some time and reduce mistakes. Lastly, do we really need to type njaccess every time? Let's shorten it to something like soc—subscriber only content. For our first dilemma, a better idea than groups might be to associate the access to certain AEC subscriptions that are currently active. That way if people's subscriptions expire, or they get a free account, the content is still properly controlled regardless of their user groups.

Introduction Let's face it, in today's business environment, there is only one email client that truly matters. I am not saying it is the best client, or that it offers more features, and I certainly am not saying it is the most secure. What I am saying is that you would be hard pressed to walk into an organization, of let's say more than 10 desktops, and not see users checking their email with Microsoft Outlook. Zimbra Collaboration Suite offers uncanny support for Outlook including: Native Sync with MAPI Support for both Online and Offline Modes Cached mode operation Support for multiple calendars Here, we will discuss these features and focus on configuring Outlook to work with the Zimbra server. As you will see with a Zimbra back end and an Outlook client, it is transparent to your users whether you are using Microsoft Exchange or Zimbra Collaboration Suite as your back end product. This transparency to users makes the migration from Exchange to Zimbra that much easier in the eyes of your users, especially when it comes to user training. The ability to seamlessly integrate Zimbra and Outlook is one of Zimbra's strongest assets and one of its strongest arguments for making the transition from Exchange to Zimbra. However, if you want to use the full power of Zimbra (not only the fancy look but great features such as the searches), you should use the Web Client. We will take a detailed look at Zimbra integration with Outlook, including: The Zimbra Connector for Outlook (ZCO) A look at Zimbra integration Sharing Outlook folders Outlook uses the Messaging Application Programming Interface (MAPI) to allow programs to communicate with messaging systems and stores. MAPI is proprietary to Microsoft and is key to Zimbra being able to synchronize and work with Outlook. Zimbra uses a connector to facilitate this communication—called the Zimbra Connector—for Outlook. The PST Import Wizard One of the beauties of Outlook's integration in Zimbra is that you won't start from scratch: Zimbra gives you tools that are able to import your data (emails, calendars, contacts, etc) either from a concurrent solution's server (Exchange or Domino) or directly from a PST file (the file used by Outlook to store all its data).   We'll have a look at the PST Import Wizard. To download it: Log in to the Administration Console at https://zimbra.emailcs.com:7071/. Click on the Downloads tab on the left of the navigation pane. 3. In the Content Pane, click on the PST Import Wizard to download the executable file. 4. Save the file to the local computer, or a network accessible shared folder. 5. Double click the .exe file to launch the wizard (there's no installation process). 6. Click on Next on the presentation page. 7. In the Hostname field enter: zimbra.emailcs.com. 8. In the Port field you can leave the default (80) and let the Use Secure Connection box unchecked. 9. In the Username field, enter your Zimbra's user (worker@emailcs.com) and in the Password field your Zimbra's password. Click on the Next button. You will now have to select the PST file that you want to import into the Zimbra server. The Zimbra Import Wizard helps you as it opens the default Outlook PST's directory when you click on the Browse button. Once you have selected the PST you want to import and clicked on the Open button, you can now click on the Next button of the initial window. Now, you can choose how your data will be imported: Import Junk-Mail Folder: If you leave this box checked, all your spam will be imported to the server and marked as spam on the server. Import Deleted Items Folder: With this, the deleted mails will be imported on the server. Ignore previously imported items: This option is used when you're importing your data in several attempts. If you leave it checked, the already imported mails won't be imported again. Import items received after: Checking this box and choosing a date in the calendar next to it, allows us to do a partial import based on date. Import messages with some headers but no message body: You should leave this one checked as it imports some badly formatted mails. Convert meeting, organized by me, from my old address to my new address: You need to check this box (and enter your previous email address) if you're getting a new email address on the Zimbra server. If you don't, the meetings will be imported but you won't be the owner. Migrate private appointments: This one is your own choice as Zimbra does not handle (yet) the private items; all the imported appointments will be viewable by anyone you share your calendar with.   Once your choices are made, you can click on the Next button. 14. Click OK in the confirmation window. 15. Next window will show you the import evolution (number of items and percentage). You can stop the import at anytime and start again later. Once the import is finished, a window pops up with a summary of the import session. 16. You can click on the OK button of the summary window then Finish in the last window. The Zimbra Connector for Outlook The Zimbra Connector for Outlook (ZCO) is a downloadable .msi installable file that must be installed on the desktop in order for Outlook and Zimbra to communicate. To download the ZCO to the client: Log in to the Administration Console at https://zimbra.emailcs.com:7071. Click on the Downloads tab on the left of the navigation pane. 3. In the Content Pane, click on the Zimbra Connector for Outlook to download the .msi installable file. Save the file to the local computer, or a network accessible shared folder. Double click the .msi file to start the installation process. The installation wizard will begin and go ahead and accept the License Agreement and accept all of the defaults. Once complete click FINISH. The ZCO creates a brand new profile within Outlook, called Zimbra. If you had previous profile(s) created on your computer, be sure to choose the "Zimbra" one. The ZCO is now installed, and the first time we run Outlook on this client, the connector will prompt us for configuration information. Zimbra currently supports Outlook 2003 only. In the Server Name field, enter: zimbra.emailcs.com. For port leave the default of 80. Email address will be the email address for this user. In our case, we will use the Worker Bee with an email address of worker@emailcs.com. For the password, enter the same password Worker would use to log in to the AJAX web client. Once completed, click OK and Outlook will open Worker's email box. The ZCO will now sync the Global Access List and will get all the emails from the server locally. It means that if you imported lots of item previously, you might need some time to get them back into Outlook from the server. Luckily, then the sync process happens in the background. As you can see in the following screenshot, the folders we created in the Web Client are now configured in Outlook. The first time Outlook is opened, it automatically performs a send/receive with the Zimbra server. After this initial synchronization, there is nothing a user needs to do from then on to initiate synchronization with the server. There is also nothing the user needs to set-up to let Outlook know whether or not the user is Online—connected to the server, or Offline—disconnected from the server. Outlook automatically checks the status and acts accordingly. Therefore, a user need not be connected to the server to work with email that has already been received, check the address book, or work with the Calendar. All changes that the user makes in Offline mode, will synchronize with the server the next time the server is connected and Outlook is online. At this time, we should take a quick look around Outlook and see how integrated Zimbra really is with Outlook. A Look at Zimbra Integration The integration of Zimbra is more than just the ability to send and receive email. Outlook is now acting as the front end to create contacts, appointments, and tasks that will be stored on the server. Let's take a moment to look at each one individually. Contacts The easiest way to see the integration of contacts between Outlook and Zimbra is to compose a new mail message, and instead of typing in an email address, click on the TO: button and select Global Address List from the Address Book drop-down menu. As you can see, this feature looks exactly the same whether you are using Exchange or Zimbra as your back end collaboration server. Users are familiar with this look and feel, and the ability to select users that are within the organization's Global Address List. This list comes directly from the Zimbra server and is maintained there as well. The user also has the option to select the own personal contact list. This list could be created and maintained either via the web client, through Outlook directly, or both as they will synchronize together. Appointments In most work organizations, the ability to create appointments, invite people to attend, and check invitees schedule is a key function of Exchange and Outlook. Luckily for us, the same functionality could be used with Zimbra and Outlook. As seen in the following figure, the process for creating an appointment is exactly the same. In the Calendar application, click New --> Appointment. Click on the Invite Attendees button. Click the To button and select the Global Address List from the drop-down menu. Select the CEO from the address list and click OK. Click on the Scheduling tab.   The Calendar is synced with the Zimbra server and is able to check the availability of the users within the organization, a key feature of any collaboration suite. Once you have found a schedule when all the attendees are free, go back to the Appointment tab, type in a Subject for your appointment then click on the Send button. The last feature we will look at is Sharing Outlook folders. Sharing Outlook Folders Users have the option to share any Outlook folder with users in the Global Address List. Essentially, this is the same ability we covered in an earlier chapter with the Web Client for the Contacts or Calendar. However, here the process is different. Users could be delegated different levels of access to Outlook folders. These levels include: Read View items in folder only Edit Edit any contents in the folder Create Create/add items to the folder Delete Delete/modify items in the folder Act on workflow Respond to meeting and task requests Administer Folder Modify the permissions on the folder There are also predefined roles that users could assign to other users in the Global Address List including: Administrator Has all rights to the folder listed above Delegate Has access to all rights except for Administer folder Editor Access to Read, Edit, Create and Delete Author Access to Read and Create Reviewer Read only To assign roles and rights to the folder: 1. Right click the folder and click Properties. 2. Click on the Sharing tab. 3. Click Add and select CEO from the Global Address List. 4. With CEO highlighted, select Administrator from the Permission Level drop-down-box. 5. With Administrator selected, you should be able to see all of the Permissions selected. 6. Change the Permission Level to Reviewer and you will see that only Read items, is selected. 7. Go ahead and play with the various levels so you can get a feel for the different permissions associated with the various levels. 8. Once complete, click OK. An email will be sent to the CEO informing him that he now has Administrator access to the Inbox of the Worker Bee. In order for the CEO to work with the new Shared Folder (the Worker's Inbox in this case), the CEO would simply: 1. Click on File --> Open --> Other User's Mailbox in the Outlook Menu bar. 2. Select Worker from the Global Address List. 3. Once the folder is added to Outlook, click on the Send/Receive button to synchronize the folder. Summary The goal of this article was to take a brief look at using the Microsoft Outlook client as a front end to the Zimbra Collaboration Suite. In my experience, users do not like change and they tend to be comfortable with applications they are familiar with. One of the most common objections to changing email systems is that users rely so heavily on their email and contacts that they do not want to have to learn a whole new system to access them. Hopefully, if I have done my job, you could now see how users need not be afraid of moving to a Zimbra system, because in the end, their everyday life and functionality is not going to change much. They could still use the tool that they are most familiar with, but still have the added benefit of using the AJAX Web Client when they are on the road or away from their desks.

Introduction If you work with IP telephony, it's quite possible that you have not heard about OpenSER, but certainly you must have heard about Asterisk. Well, I love a polemic headline and I have seen this question asked in the forums many times.  So, I will dare to compare these two very popular softwares dedicated to the VoIP market.  The idea here is not to show you which one is the best, but mainly how they are different from each other. Below is a comparison topic by topic. Architecture Asterisk is a Back to Back User Agent (B2BUA), while OpenSER is a Session Initiation Protocol (SIP) Proxy.  This makes all the difference between them. The SIP proxy architecture is faster than a B2BUA because it deals only with signaling. On the other hand, the B2BUA architecture, even being slower, handles the media and it is capable of several services not available in a SIP proxy such as Codec Translation (that is G729<->G.711), Protocol Translation (SIP<->H323), and services related to media such as IVR, Queuing, Text to Speech, and Voice Recognition. Nat Traversal OpenSER deals a lot better with NAT traversal then Asterisk. You can send the media from your customer directly to the provider using OpenSER in most cases (non-symmetric NAT). Manipulating directly the SIP protocol allows you to handle special cases, such as, when you have two customers behind the same NAT device and want to send the media directly between them. Load Balancing OpenSER has specific load balancing algorithms with hash. So it can load balance by the "ruri", "username", "call-id", and some other properties. It can use redirected messages consuming very few resources from the load balancer machine. Failover is part of the solution, things you won't find on Asterisk, but are complementary. Low Level Access to SIP Header and Transactions OpenSER gives you low level access to the protocol. You can handle all the requests and responses. So it is possible, most times, to translate between two incompatible versions of SIP, handling directly the SIP headers, requests, and responses. This is an important feature when you have SIP implementations from different manufacturers, which can be incompatible between each other. Integration with Radius, Diameter, and LDAP OpenSER has built-in integration with LDAP, Radius, and Diameter. While this is also possible with Asterisk, the implementation on OpenSER is developed in C, integrated as a module, and is part of the OpenSER distribution (no perl, no python, no third-party modules). Carrier Class Routing The module CARRIERROUTE implements sophisticated algorithms to route calls to the PSTN. Some times VoIP providers have tables with more then 40.000 routes. In this case, you will absolutely need a specific routing module capable of failback, blacklists, and some other features specific to VoIP providers. Media Services OpenSER is a SIP Proxy and is not capable of any media related services. So it is not possible to create, using OpenSER, systems such as VoiceMail, IVR, TTS, and Voice Recognition. However, it is possible to integrate any of these services to the platform using a separate Media Server such as Asterisk, Yate, and FreeSwitch.  This is by design, and it is the way the SIP protocol is defined in the standards (RFC3261). Connectivity to the PSTN OpenSER always need a SIP gateway to connect to the PSTN. There is no possibility to install telephony cards in the server.  In several cases, Asterisk is used as the PSTN gateway for OpenSER. Conclusion I love this discussion, because Asterisk and OpenSER completes one another. OpenSER provides rock solid SIP services to VoIP providers, it is capable to handle large volumes of calls, to load balance SIP, to solve advanced NAT scenarios, and to deal with SIP signaling as no other. Asterisk is a B2BUA, very strong in the PBX market. It is simpler to configure and can handle low to medium volumes. Asterisk can be used as a "single box does it all", while OpenSER requires all the architectural components of SIP to work. OpenSER is a "hit" in the VoIP provider market and in Universities. Asterisk PBX is a success in the IP PBX market, and it is getting a piece of the small to medium VoIP providers. Usually you start using OpenSER when you have some special need, such as load balancing or when you have large volumes such as more than a thousand registered users. Choose wisely!   If you have read this article you may be interested to view : Using Asterisk as a PSTN Gateway for OpenSER Building the User Portal with SerMyAdmin for OpenSER

Advanced Parameters The Advanced Parameters settings, shown as follows, are accessed by clicking on the Advanced Parameters item in the lefthand menu and are a collection of AudiCodes-specific settings. The following configuration options are available on this page (click on Show Advanced Settings to reveal all options): Secure SIP Calls: If this is enabled, gateways will only accept SIP calls from IP addresses listed below. The default is disabled (unchecked) Accepted IP Addresses: They are used in conjunction with the above setting. It is a space-separated list of IP addresses from which gateway will accept the calls. It is taken into account only if Secure SIP Calls is enabled. The default is the IP address provided for the PBX during install. Digit Delivery to Telephony Port: This setting enables a digit string to be played to the port at the far end, after off-hook. The default is disabled (unchecked). Digit Delivery to IP: This setting enables a digit string to be played to the port at the far end, after off-hook. The default is disabled (unchecked). DID Wink Support: When this is enabled, the gateway can connect to EIA/TIA 464B Loop Start DID lines. Both generation and detection are supported. The default setting is disabled (unchecked). Enable Call Disconnect on Polarity Reversal: If this is checked, enables port disconnect (on-hook) based on polarity reversal. Some POTS providers will reverse the polarity of the analog phone line to signal disconnection to a PBX. The default is disabled (unchecked). Enable Call Disconnect on Current Drop: If this is set to 1, enables port disconnect (on-hook) based on current drop. The default setting is disabled (0). Enable Call Disconnect on Broken Connection: If this is checked, the call is released if the gateway stops receiving RTP for a period of time. The default is enabled (checked). Broken Connection Timeout (10msec): The amount of time for which RTP is not received, before the call is cleared. In 10 ms steps, the default is 500, 10 ms steps (5 seconds). Enable Call Disconnect on Far End Silence: If this checked, enables disconnection of call based on silence. The default is disabled (unchecked). Silence Period for Disconnect: The detection period, in seconds, before the call is released based on silence. The default is 120 seconds. Silence Detection Method: This setting can be set to "None" (silence detection option is disabled), "Packets Count" (according to packet count), "Voice/Energy Detectors" (according to energy and voice detectors (default)) or "All" (according to packet count and energy / voice detectors). Silence Threshold: The threshold of packet count, in percentage, below which is considered as silence. The default setting is 8 packets. Detail Level in Debug Log: The detail level of the log messages sent to syslog server. Default is 0 (off), max is 5 (full). CDR Server IP Address: An optional separate syslog server to collect CDRs only. If null and CDR is enabled, the output is mixed with the log messages and is routed to the syslog server IP. (Default: 0.0.0.0) CDR Report Level: This can be set to "None", (Call Detail Recording or CDR information isn't sent to the Syslog server, which is the default value), "End Call" (CDR information is sent to the Syslog server at the end of each Call) and, "Start & End Call" (CDR information is sent to the Syslog server at the start and at the end of each Call). Port Busy-Out Method  : If there is a network-side failure on the gateway, the POTS interfaces can be set to busy. If this is  checked, telephony ports are busied out (special tone) in case of LAN failure or proxy communication failure. The default is disabled (unchecked). Delay After Reset [sec]: Amount of time delay before answering calls after gateway reset. The default is 7 seconds. Max Number of Active Calls: This is the maximum number of active calls the PBX can process. It should be set to the number of PSTN lines active. Max Call Duration [min]: This is the maximum duration of a phone call. The default is 0, which means no maximum. Enable LAN Watchdog: When LAN Watchdog is enabled, the gateway's overall communication integrity is checked periodically. If no communication for about 3 minutes is detected, the gateway performs a self test. If the self test succeeds, the problem is logical link down (for example, Ethernet cable disconnected on the switch side), and the "Busy Out" mechanism is activated if enabled (EnableBusyOut = 1). Lifeline is activated if enabled. If the self test fails, the gateway restarts to overcome an internal fatal communication error (default: unchecked). Enable SAS: This setting is to enable/disable Stand-Alone Survivability (SAS) (default: unchecked). • SAS Registration Time: This is the time after which SAS is enabled (default: 20 seconds). SAS Local SIP UDP port: This is the UDP Port for SAS SIP signaling (default: 5080). SAS Local SIP TCP port: This is the TCP Port for SAS SIP signaling (default: 5080). SAS Local SIP TLS port: This is the TLS Port for SAS SIP signaling (default: 5081). SAS Default Gateway: This is the SAS Default Gateway IP address (default blank). SAS Short Number Length: This is the SAS short number length. Click on the Apply button to keep any changes made on this page.

Sending emails Joomla!'s core content management has a built-in feature where visitors are able to send articles to their friends through email. A similar feature can be added to the "Restaurant Reviews" component. The component can be modified to display a link to a form where the email address of a friend can be entered along with a short message. We will create a new view to handle this form. Go to the /components/com_restaurants/views folder of your Joomla! component and create a new folder named email. In this folder, create a file called view.html.php, and load it with the following code: <?phpdefined( '_JEXEC' ) or die( 'Restricted access' );jimport( 'joomla.application.component.view');JTable::addIncludePath(JPATH_COMPONENT_ADMINISTRATOR . DS . 'tables');class RestaurantsViewEmail extends JView{ function display($tpl = null) { $id = JRequest::getInt('id', 0); $review =& JTable::getInstance('review', 'Table'); $review->load($id); $this->assignRef('review', $review); parent::display($tpl); }} This code first checks to make sure that the file is not being called directly, loads in the framework code for views, and adds /administrator/components/com_restaurants/tables to the include path list of JTable. After declaring RestaurantsViewEmail as an extension of JView, the display() function pulls in the restaurant review ID from the request. The getInstance() member function of JTable is used to get a reference to a table object for reviews. The review matching the ID is then loaded and assigned to the template using the assignRef() member function. Finally, JView's original display() member function is called. Although the code in view.html.php now loads the review that our visitors are trying to email, the form still needs to be added. Create a folder named tmpl in the existing /components/com_restaurants/views/email folder, and create a new file default.php inside it with the following code: <?php defined( '_JEXEC' ) or die( 'Restricted access' ); ?><form action="index.php" method="post"> <div class="contentheading">Email review</div> <p>&nbsp;</p> <p>Fill this form to send this review of <em> <?php echo htmlspecialchars($this->review->name) ?> </em> to someone you know who will find it useful:</p> <div> <strong>Your name:</strong> </div> <p> <input type="text" name="sender_name" value="" /> </p> <div> <strong>Your email address:</strong> </div> <p> <input type="text" name="sender_email" value="" /> </p> <div><strong>Recipient's email address:</strong></div> <p> <input type="text" name="recipient" value="" /> </p> <div><strong>Message:</strong></div> <p> <textarea name="message" rows="4" cols="40"></textarea> </p> <p> <input type="submit" value="Send Review" class="button" /> </p> <?php echo JHTML::_( 'form.token' ); ?> <input type="hidden" name="id" value= "<?php echo $this->review->id; ?>" /> <input type="hidden" name="task" value="sendemail" /> <input type="hidden" name="option" value= "<?php echo $option; ?>" /></form> Before any output occurs, the code checks to make sure that the request is coming from within Joomla! and is not being called directly. The file then outputs a brief message identifying the review by name, so that the visitors are sure of what they are sending. The form then continues with fields for the visitor's name and email address, the email address of their friend, and an optional message. Just after the submit button, there is a series of hidden fields. First, JHTML::_('form.token') is called to generate a token for the request. This is the same style of token as is used in the backend to thwart CSRF attacks, only here it is used to cut down on abuse. Next, the ID of the review being emailed is placed into the form. The task variable is set to sendemail, which is a function that we will add to the controller in a moment. Finally, option is set, so that Joomla! loads the com_restaurants component. Linking the form If you now load index.php?option=com_restaurants&view=email in your browser, you will see this screen: The message at the top of the screen is incomplete as we simply loaded the view without a review id. Although we could add id as a parameter onto the end of the URL, our visitors will not be doing this. They will need a link to follow from the review itself. To add this link, we need to make some small adjustments to the single view. This view first needs to generate URLs to the email view with the ID already included. Do this by making the following highlighted adjustment to the display() function in /components/com_restaurants/views/single/view.html.php: $date = JHTML::Date($review->review_date);$backlink = JRoute::_('index.php?option=com_restaurants');$emaillink = JRoute::_('index.php?option=com_restaurants&view=email&id=' . $id);$user =& JFactory::getUser();$comments =& $this->get('Comments');$this->assign('display_comments', $params->get('display_comments', '1'));$this->assignRef('review', $review);$this->assignRef('smoking', $smoking);$this->assignRef('date', $date);$this->assignRef('backlink', $backlink);$this->assignRef('emaillink', $emaillink);$this->assignRef('name', $user->name);$this->assignRef('comments', $comments);parent::display($tpl); With a URL to the email view now being generated, we now need to display it. Open /components/com_restaurants/views/single/tmpl/default.php and add the following highlighted code: <p><?php echo htmlspecialchars($this->review->review); ?></p><p><em>Notes:</em> <?php echo htmlspecialchars($this->review->notes); ?></p><p><a href="<?php echo htmlspecialchars($this->emaillink); ?>">Email this to a friend</a></p><a href="<?php echo htmlspecialchars($this->backlink); ?>">&lt; return to the reviews</a> After saving the files, navigate to one of the restaurant reviews in the frontend. Your screen should now have an Email this to a friend link, like the following screenshot: When you click on the Email this to a friend link, you will get a screen that looks like the following: Sending email With the form and the navigation in place, we can now focus on creating the function that creates the email and sends it to the correct place. Throughout the creation of this component, we have used member functions of JRequest to filter our input. We will do the same here, but go one step further by verifying that the mail addresses entered are valid. This extra step is necessary as malicious users can otherwise add invalid newline characters to your email fi elds, taking control of the message sending process. Once a remote user has control, the message can be sent anywhere with any text. This is known as an "Email Header Injection attack". If you fail to protect your website against this type of attack, your component could be hijacked and used to send thousands of spam messages without your knowledge. With this caution in mind, we will write the sendemail() function to process the form and send the review. Open /components/com_restaurants/restaurants.php and add this function to the controller class: function sendemail(){ JRequest::checkToken() or jexit( 'Invalid Token' ); JTable::addIncludePath(JPATH_COMPONENT_ADMINISTRATOR . DS . 'tables'); $sender_email = JRequest::getString('sender_email', ''); $recipient = JRequest::getString('recipient', ''); $sender_name = JRequest::getString('sender_name', ''); $message = JRequest::getString('message', ''); $id = JRequest::getInt('id', 0); jimport( 'joomla.mail.helper' ); if (!JMailHelper::isEmailAddress($sender_email) || !JMailHelper::isEmailAddress($recipient)) { JError::raiseError(500, 'One of the emails you entered is invalid. Please try again.'); } $review =& JTable::getInstance('review', 'Table'); $review->load($id); $link = JURI::base() . 'index.php?option=com_restaurants&view= single&id=' . $id; $subject = $sender_name . ' wants you to know about ' . $review->name; $body = "Here's a review of {$review->name}:nn"; $body .= "{$review->review}nn"; if ($message != '') { $body .= $sender_name . " also added this message:n"; $body .= '"' . $message . '"' . "nn"; } $body .= "For all of the details, follow this link: {$link}"; $sender_name = JMailHelper::cleanAddress($sender_name); $subject = JMailHelper::cleanSubject($subject); $body = JMailHelper::cleanBody($body); if (JUtility::sendMail($sender_email, $sender_name, $recipient, $subject, $body) !== true) { JError::raiseNotice( 500, 'Email failed.' ); } JRequest::setVar('view', 'email'); JRequest::setVar('layout', 'success'); $this->display();} Before even checking the variables, the checkToken() member function of JRequest is called to make sure that the user actually loaded the form. Although this will not prevent spammers from abusing your component, it will slow them down; they will need to load your form and extract the token for each message. Next, the path /administrator/components/com_restaurants/tables is added to the list of paths JTable will use to find table classes. This is necessary because we will be loading the review in a moment, in order to extract the summary and title. The email address of the sender, the address of the recipient, the name of the sender,any added message, and the review's ID are all extracted from the HTTP request.With the exception of the id field, all fields are filtered as strings. The id field is more stringently filtered to ensure that the value is also an integer. Joomla! has a library for handling email data, which we pull in by calling jimport( 'joomla.mail.helper' );. This is used immediately to ensure that the entered email addresses are in a valid format. Both the sender's address and the recipient's address are tested. If either one is in an invalid format or contains newlines, the raiseError() member function of JError is used to stop the script and display a message. The function continues by generating some review-specific data. The review is loaded from the database, and then a link back to the review is built using the review's ID. A subject line is built with the sender's name and the name of the restaurant. The body of the email starts with the name of the review, followed by the review itself. If the visitor added a personal message then this is added, along with their name. The link to the full review is added at the end. With all of the content generated, there is one step left before sending the message. The formats of the email addresses have already been validated, but the sender's name, subject, and body all contain user-supplied data. These must be filtered before they are sent off. The cleanAddress(), cleanSubject(), and cleanBody() member functions of JMailHelper strip out any attempts at email header injections. Finally, the sendMail() member function of JUtility is called to send the email with the sender's address, sender's name, recipient's email address, subject line, and body as the respective parameters. If this function fails for any reason, the raiseError() member function of JError is called and processing stops. Adding a success message When you perform an action that sends an email, most web applications will display an "email success" screen letting you know that the message went through. Our component will be no different. At the end of the sendemail() function, we set the view request variable to email, set the layout request variable to success, and then call the display() member function that defaults to JView::display(). Why aren't we calling $this->setRedirect()?Typically, $this->setRedirect() would be called to tell the controller to redirect the user to a specific page. This time, we have chosen to instead set the request variables and call the display() function directly. This prevents Joomla! from sending a redirect HTTP header to the browser, which ultimately saves another trip to the server. Because we want to display a message instead of going back to the review straight away, this makes sense. It may also be useful in cases where you have a client-side application that would otherwise be confused by a redirect. Instead of creating an entirely separate view to handle the success screen, we have opted instead to set the layout request variable and point back to the email view. This helps us to cut down on the number of views required, and allows us to reuse some of the view code. To add the markup for the success screen, we need to create a new file called success.php to the tmpl folder of the email view. Enter the code below in success.php: <?php defined( '_JEXEC' ) or die( 'Restricted access' ); ?><div class="componentheading">Success!</div><p>The review for <?php echo htmlspecialchars($this->review->name) ?> has been successfully emailed.</p><p><a href="<?php echo htmlspecialchars($this->reviewlink) ?>">Return to the review for <?php echo htmlspecialchars($this->review->name) ?>.</a></p> After checking to make sure that the request to success.php is coming from within Joomla!, a confirmation message, including the name, of the review is displayed. A link back to the review is also output. However, the URL for this link has not yet been generated. To do this, go to /components/com_restaurants/views/email/view.html.php and add the highlighted code to the display() function: $review->load($id);$reviewlink = JRoute::_('index.php?option=com_restaurants&view= single&id=' . $id);$this->assignRef('review', $review);$this->assign('reviewlink', $reviewlink);parent::display($tpl); Save all of your code, then load one of the reviews and click on the Email this to a friend link. Fill the form and click the Send Review button. If the email goes through correctly, you should see a screen like the following: If you sent the review to yourself, the email should look similar to the following: Here's a review of The Daily Dish: Chicken fried steak, meatloaf, potatoes, string beans and hot turkey sandwiches are all favorites from this venerable institution the locals swear by. Apple, pumpkin, and pecan pies round out the dessert selection.Dinner there won't break the bank, either. Ralph Elderman also added this message:"You should really try this place sometime. I take the family there every week!" For all of the details, follow this link: http://localhost/index.php?option=com_restaurants&view=single&id=2

Customizing the home page in Grails With tagging in place, we can enhance the application to allow users to create their own home page. The aim is to allow users to specify the tags they are interested in, so any content with these tags will be displayed on their home page. This will allow us to break the home page up into two sections: A Most Recent section, containing the last five file uploads and messages A Your Data section, containing all the files and messages that are tagged according to the user's preferences Introducing templates Taking this approach means that files and messages will be displayed in many different places on the site, instead of just the home page. By the end of this article, messages and files will be rendered in the context of: A Most Recent section A Your Data section In the future, we will probably render messages and files in the following contexts as well: Show all files and messages Show files and messages by tags Show files and messages by search results Ideally we want to encapsulate the rendering of a file and a message so they look the same all over the site, and we don't need to duplicate our presentation logic. Grails provides a mechanism to handle this, through GSP, called templates. A template is a GSP file, just the same as our view GSP files, but is differentiated from a view by prefixing the file name with an underscore. We are going to create two templates—one template for messages, which will be called _message.gsp and the other for files, which will be called _file.gsp. The templates will be responsible for rendering a single message and a single file. Templates can be created anywhere under the views folder. The location that they are created in affects the way they are executed. To execute a template we use the grails render tag. Assume that we create our message template under the views/message folder. To render this template from a view in the same folder, we would call the following: <g:render template="message" /> However, if we need to render a message from another controller view, say the home page, which exists under views/home, we would need to call it like so: <g:render template="/message/message" /> Passing data to a template The two examples of executing a template above would only be capable of rendering static information. We have not supplied any data to the template to render. There are three ways of passing data into a template: Send a map of the data into the template to be rendered Provide an object for the template to render Provide a collection of objects for the template to render Render a map This mechanism is the same as when a controller provides a model for a view to render. The keys of the map will be the variable names that the values of the map are bound to within the template. Calling the render tag given below: <g:render template="message" model="[message: myMessage]" /> would bind the myMessage object into a message variable in the template scope and the template could perform the following: <div class="messagetitle"> <g:message code="${message.title}" encodeAs="HTML"/></div> Render an object A single object can be rendered by using the bean attribute: <g:render template="message" bean="${message}" /> The bean is bound into the template scope with the default variable named it: <div class="messagetitle"> <g:message code="${it.title}" encodeAs="HTML"/></div> Render a collection A collection of objects can be rendered by using the collection and var attributes: <g:render template="message" var="message" collection="${messages}" /> When using a collection, the render tag will iterate over the items in the collection and execute the template for each item, binding the current item into the variable name supplied by the var attribute. <div class="messagetitle"> <g:message code="${message.title}" encodeAs="HTML"/></div> Be careful to pass in the actual collection by using ${}. If just the name of the variable is passed through, then the characters in the collection variable name provided will be iterated over, rather than the items in the collection. For example, if we use the following code, the messages collection will be iterated over: <g:render template="message" var="message" collection="${messages}" /> However, if we forget to reference the messages object and just pass through the name of the object, we will end up iterating over the string "messages": <g:render template="message" var="message" collection="messages" /> Template namespace Grails 1.1 has introduced a template namespace to make rendering of templates even easier. This option only works if the GSP file that renders the template is in the same folder as the template itself. Consider the first example we saw when rendering a template and passing a Map of parameters to be rendered: <g:render template="message" model="[message: myMessage]" /> Using the template namespace, this code would be simplified as follows: <tmpl:message message="${myMessage}"/> As we can see, this is a much simpler syntax. Do remember though that this option is only available when the GSP is in the same folder as the template. Create the message and file templates Now, we must extract the presentation logic on the home page, views/home/index.gsp, to a message and file template. This will make the home page much simpler and allow us to easily create other views that can render messages and files. Create two new template files: /views/message/_message.gsp /views/file/_file.gsp Taking the code from the index page, we can fill in _message.gsp as follows: <div class="amessage"> <div class="messagetitle"> <g:message code="message.title" args="${[message.title]}" encodeAs="HTML"/> </div> <div class="tagcontainer"> <g:message code="tags.display" args="${[message.tagsAsString]}" /> </div> <div class="messagetitlesupplimentary"> <g:message code="message.user" args="${[message.user.firstName, message.user. lastName]}"/> </div> <div class="messagebody"> <g:message code="message.detail" args="${[message.detail]}" encodeAs="HTML"/> </div></div> Likewise, the <div> that contains a file panel should be moved over to the new _file.gsp. This means the main content of our home page (views/home/index.gsp) becomes much simpler: <div class="panel"> <h2>Messages</h2> <g:render template="/message/message" collection="${messages}" var="message"/></div><div class="panel"> <h2>Files</h2> <g:render template="/file/file" collection="${files}" var="file"/></div> User tags The next step is to allow users to register their interest in tags. Once we have captured this information then we can start to personalize the home page. This is going to be surprisingly simple, although it sounds like a lot! We just need to: Create a relationship between Users and Tags Create a controller to handle user profiles Create a form that will allow users to specify the tags in which they are interested User to tag relationship Creating a relationship between users and tags is very simple. Users will select a number of tags that they want to watch, but users themselves are not 'tagged', so the User class cannot extend the Taggable class. Otherwise users would be returned when performing a polymorphic query on Taggable for all objects with a certain tag. Besides allowing a user to have a number of tags, it is also necessary to be able to add tags to a user by specifying a space delimited string. We must also be able to return the list of tags as a space delimited string. The updates to the user class are: package appimport tagging.Taggerclass User { def tagService static hasMany = [watchedTags: Tagger] ... def overrideTags( String tags ) { watchedTags?.each { tag -> tag.delete() } watchedTags = [] watchedTags.addAll( tagService.createTagRelationships( tags )) } def getTagsAsString() { return ((watchedTags)?:[]).join(' ') }} User ProfileController The ProfileController is responsible for loading the current user for the MyTags form, and then saving the tags that have been entered about the user. Create a new controller class called ProfileController.groovy under the grails-app/controller/app folder, and add the following code to it: package appclass ProfileController { def userService def myTags = { return ['user': userService.getAuthenticatedUser() ] } def saveTags = { User.get(params.id)?.overrideTags( params.tags ) redirect( controller:'home' ) }} The myTags action uses userService to retrieve the details of the user making the request and returns this to the myTags view. Remember, if no view is specified, Grails will default to the view with the same name of the action. The saveTags action overrides the existing user tags with the newly submitted tags The myTags form The last step is to create the form view that will allow users to specify the tags they would like to watch. We will create a GSP view to match the myTags action in ProfileController. Create the folder grails-app/views/profile and then create a new file myTags.gsp and give it the following markup: <%@ page contentType="text/html;charset=UTF-8" %><html><head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <meta name="layout" content="main"/> <title>My Tags</title></head><body><g:form action="saveTags"> <g:hiddenField name="id" value="${user.id}"/> <fieldset> <dl> <dt>My Tags</dt> <dd><g:textField name="tags" value="${user.tagsAsString}" size="35" class="bigfield"/></dd> </dl> </fieldset> <g:submitButton name="Save" value="Save"/> | <g:link controller="home">Cancel</g:link></g:form></body></html> This view will be rendered by the myTags action on the ProfileController and is provided with a User instance. The form submits the tags to the saveTags action on the ProfileController. The user id is put in a hidden field so we know which user to add the tags to when the form is submitted, and any existing tags for the user are rendered in the text field via the tagsAsString property. Add a link to the myTags action in the header navigation from our layout in main.gsp: <div id="header"> <jsec:isLoggedIn> <div id="profileActions"> <span class="signout"> <g:link controller="profile" action="myTags">My Tags</g:link> <g:link controller="auth" action="signOut">Sign out</g:link> </span> </div> </jsec:isLoggedIn> <h1><g:link controller="home">Teamwork</g:link></h1></div> Now restart the application, log in as the default user and you will be able to specify which tags you are interested in.

Documentation—if there is one word that installs fear in most developers, it must be this one. No one in their right mind would argue the value of documentation, but it is the actual act of writing it that concerns developers so. The secret of creating good documentation is to make the process of doing so as painless as possible, and if we are lucky maybe even attractive, to the developers. The only practical way to achieve that is to reduce friction. The last thing we need when we are in middle of fixing a bug is to wrestle with our word processor, or even worse try to find the right document to update. What's in a name?Throughout the rest of this article, we will refer to various URLs that point to specific areas of our Trac environment, Subversion repository, or WebDAV folders. Whenever you see servername, replace it with your own server name. Making Documentation Easy One of the reasons Trac works so well for managing software development is because it is browser based. Apart from our development environment, the browser, along with our email client, are the next most likely applications we are going to have installed and running on our computer. If access to our Trac environment is only a click away, it stands to reason that we are more likely to use it. We can refer to Trac as a "wiki on steroids" because of the way the developers have integrated the typical features of a wiki throughout the whole product. However, for all the extra features and integration, at its heart Trac is basically just a wiki and this is the main reason why it so useful in helping smooth the documentation process. A wiki is a web application that allows visitors to create and modify its content. Let's expand on that slightly. As well as letting us view content—like a normal website—a wiki lets us create or edit the content as we desire. This could take the form of creating new content, or simply touching up the spelling on something that already exists. While the general idea with a wiki is that anyone can edit them, in practice this can lead to abuse, vandalism, or spam. The obvious solution to this is to involve people to authenticate the edit. Do we really need this security?Yes. Having these security requirements provides us with accountability. We will always be able to see when something is done, but by enforcing security we can see who did it. While this does cause some administrative overhead to create and maintain authentication details for anyone involved with our development projects, the benefits outweigh the costs. Accessing Trac Before we look at how to modify and create pages, let's see how our Trac environment looks to a normal (i.e. unauthenticated) user. To do this we need to open our web browser and enter the URL http://servername/projects/sandbox into the address bar and then press the Enter key. This will take us to the default page (which is actually called WikiStart). When we access our project as an unauthenticated (or anonymous in Trac parlance) user, the majority of it will look and act like a normal website and the wiki in particular seems just like the usual collection of interlinked pages. However, as soon as we authenticate ourselves to Apache (which passes that information on to Trac), it all changes. If we click the Login link in the top right of the page now, we will be presented with our browser's usual authentication dialog box as shown in the following screenshot. Input the proper username and password and click OK. If we enter them correctly we will be taken back to the same page, but this time there will be two differences. Firstly, instead of the login link we will see the text logged in as followed by the username we used and a Logout link. Secondly, if we scroll to the bottom of the page there are some buttons that allow us to modify the page in various ways. Anonymous users have permission to only view wiki pages, while authenticated users have full control. We should try that out now—click the Logout link and scroll down again, and you will see that the buttons are absent.

Essentially, AJAX is an acronym for Asynchronous JavaScript and XML, and it is the technique of using JavaScript and XML to send and receive data between a web browser and a web server. The biggest advantage this technique has is that you can dynamically update a piece of content on your web page or web form with data from the server (preferably formatted in XML), without forcing the entire page to reload. The implementation of this technique has made it obvious to many web developers that they can start making advanced web applications (sometimes called RIAs—Rich Interface Applications) that work and feel more like software applications, instead of like web pages. Keep in mind that the word AJAX is starting to have its own meaning (as you'll also note its occasional use here as well as all over the web as a proper noun, rather than an all-cap acronym). For example, a Microsoft web developer may use VBScript instead of JavaScript to serve up Access Database data that is transformed into JSON (not XML) using a .NET server-side script. Today, that guy's site would still be considered an AJAX site, rather than an AVAJ site (yep, AJAX just sounds cooler). In fact, it's getting to the point where just about anything on a website (that isn't in Flash) that slides, moves, fades, or pops up without rendering a new browser window is considered an 'Ajaxy' site. In truth, a large portion of these sites don't truly qualify as using AJAX, they're just using straight-up JavaScripting. Generally, if you use cool JavaScripts in your WordPress site, it will probably be considered 'Ajaxy', despite not being asynchronous or using any XML. Want more info on this AJAX business? The w3schools site has an excellent introduction to AJAX, explaining it in straight-forward, simple terms. They even have a couple of great tutorials that are fun and easy to accomplish, even if you only have a little HTML, JavaScript, and server-side script (PHP or ASP) experience (no XML experience required) (http://w3schools.com/ajax/). You Still Want AJAX on Your Site? OK! You're here and reading this article because you want AJAX in your WordPress site. I only ask you take the just discussed into consideration and do one or more of the following to prepare. Help your client assess their site's target users first. If everyone is web 2.0 aware, using newer browsers, and are fully mouse-able, then you'll have no problems, AJAX away. But if any of your users are inexperienced with RIA (Rich Interface Application) sites or have accessibility requirements, take some extra care. Again, it's not that you can't or shouldn't use AJAX techniques, just be sure to make allowances for these users. You can easily adjust your site's user expectations upfront, by explaining how to expect the interface to act. Again, you can also offer alternative solutions and themes for people with disabilities or browsers that can't accommodate the AJAX techniques. Remember to check in with Don't Make Me Think, that Steve Krug book I for help with any interface usability questions you may run into. Also, if you're really interested in taking on some AJAX programming yourself, I highly recommend AJAX and PHP by Cristian Darie, Bogdan Brinzarea, Filip Chereches-Tosa, and Mihai Bucica. In it, you'll learn the ins and outs of AJAX development, including handling security issues. You'll also do some very cool stuff like make your own Google-style auto-suggest form and a drag-and-drop sortable list (and that's just two of the many fun things to learn in the book). So, that said, you're now all equally warned and armed with the knowledgeable resources I can think to throw at you. Let's get to it; how exactly do you go about getting something 'Ajaxy' into your WordPress site? Plug-ins and Widgets In these next few sections we're going to cover plug-ins and widgets. Plug-ins and widgets are not a part of your theme. They are additional files with WordPress compatible PHP code that are installed separately into their own directories in your WordPress installation (again, not in your theme directory). Once installed, they are available to be used with any theme that is also installed in your WordPress installation. Even though plug-ins and widgets are not the part of your theme, you might have to prepare your theme to be compatible with them. Let's review a bit about plug-ins and widgets first. Plug-ins WordPress has been built to be a lean, no frills publishing platform. Its simplicity means that with a little coding and PHP know-how, you can easily expand WordPress's capabilities to tailor to your site's specific needs. Plug-ins were developed so that even without a little coding and PHP know-how, users could add extra features and functionality to their WordPress site painlessly, via the Administration Panel. These extra features can be just about anything—from enhancing the experience of your content and forms with AJAX, to adding self-updating 'listening/watching now' lists, Flickr feeds, Google Map info and Events Calendars; you name it, someone has probably written a WordPress plug-in for it. Take a look at the WordPress Plug-in page to see what's available: http://wordpress.org/extend/plugins/ Widgets Widgets are basically just another plug-in! The widget plug-in was developed by AUTOMATTIC (http://automattic.com/code/widgets/), and it allows you to add many more kinds of self-updating content bits and other useful 'do-dads' to your WordPress site. Widgets are intended to be smaller and a little more contained than a full, stand-alone plug-in, and they usually display within the side bar of your theme (or wherever you want; don't panic if you're designing a theme without a sidebar). If you're using WordPress version 2.2 and up, the widget plug-in has become a part of WordPress itself, so you no longer need to install it before installing widgets. Just look through the widget library on WordPress's widget blog and see what you'd like! (http://widgets.wordpress.com/) Trying to download Widgets but the links keep taking you to Plug-in download pages? You'll find that many WordPress Widgets 'piggyback' on WordPress Plug-ins, meaning you'll need the full plug-in installed in order for the widget to work or the widget is an additional feature of the plug-in. So don't be confused when searching for widgets and all of a sudden you're directed to a plug-in page. WordPress Widgets are intended to perform much the same way Mac OS's Dashboard Widgets and Windows Vista Gadgets work. They're there to offer you a quick overview of content or data and maybe let you access a small piece of often used functionality from within a full application or website, without having to take the time to launch the application or navigate to the website directly. In a nutshell, widgets can be very powerful, while at the same time, just don't expect too much. Getting Your Theme Ready for Plug-ins and Widgets In this article, we'll take a look at what needs to be done to prepare your theme for plugins and widgets. Plug-in Preparations Most WordPress Plug-ins can be installed and will work just fine with your theme, with no extra effort on your part. You'll generally upload the plug-in into your wp_content/plugins directory and activate it in your Administration Panel. Here are a few quick tips for getting a plug-in displaying well in your theme: When getting ready to work with a plug-in, read all the documentation provided with the plug-in before installing it and follow the developer's instructions for installing it (don't assume just because you've installed one plug-in, they all get installed the same way). Occasionally, a developer may mention the plug-in was made to work best with a specific theme, and/or the plug-in may generate content with XHTML markup containing a specific CSS id or class rule. In order to have maximum control over the plug-in's display, you might want to make sure your theme's stylesheet accommodates any id or class rules the plug-in outputs. If the developer mentions the plug-in works with say, the Kubrick theme, then, when you install the plug-in, view it using the Kubrick theme (or any other theme they say it works with), so you can see how the plug-in author intended the plug-in to display and work within the theme. You'll then be able to duplicate the appropriate appearance in your theme.

Web Services Web services separate out the service contract from the service interface. This feature is one of the many characteristic required for an SOA-based architecture. Thus, even though it is not mandatory that we use the web service to implement an SOA-based architecture, yet it is clearly a great enabler for SOA. Web services are hardware, platform, and technology neutral The producers and/or consumers can be swapped without notifying the other party, yet the information can flow seamlessly. An ESB can play a vital role to provide this separation. Binding Web Services A web service's contract is specified by its WSDL and it gives the endpoint details to access the service. When we bind the web service again to an ESB, the result will be a different endpoint, which we can advertise to the consumer. When we do so, it is very critical that we don't lose any information from the original web service contract. Why Another Indirection? There can be multiple reasons for why we require another level of indirection between the consumer and the provider of a web service, by binding at an ESB. Systems exist today to support business operations as defined by the business processes. If a system doesn't support a business process of an enterprise, that system is of little use. Business processes are never static. If they remain static then there is no growth or innovation, and it is doomed to fail. Hence, systems or services should facilitate agile business processes. The good architecture and design practices will help to build "services to last" but that doesn't mean our business processes should be stable. Instead, business processes will evolve by leveraging the existing services. Thus, we need a process workbench to assemble and orchestrate services with which we can "Mix and Match" the services. ESB is one of the architectural topologies where we can do the mix and match of services. To do this, we first bind the existing (and long lasting) services to the ESB. Then leverage the ESB services, such as aggregation and translation, to mix and match them and advertise new processes for businesses to use. Moreover, there are cross service concerns such as versioning, management, and monitoring, which we need to take care to implement the SOA at higher levels of maturity. The ESB is again one way to do these aspects of service orientation. HTTP HTTP is the World Wide Web (www) protocol for information exchange. HTTP is based on character-oriented streams and is firewall-friendly. Hence, we can also exchange XML streams (which are XML encoded character streams) over HTTP. In a web service we exchange XML in the SOAP (Simple Object Access Protocol) format over HTTP. Hence, the HTTP headers exchanged will be slightly different than a normal web page interaction. A sample web service request header is shown as follows: GET /AxisEndToEnd/services/HelloWebService?WSDL HTTP/1.1User-Agent: Java/1.6.0-rcHost: localhost:8080Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2Connection: keep-alivePOST /AxisEndToEnd/services/HelloWebService HTTP/1.0Content-Type: text/xml; charset=utf-8Accept: application/soap+xml, application/dime, multipart/related, text/*User-Agent: Axis/1.4Host: localhost:8080Cache-Control: no-cachePragma: no-cacheSOAPAction: ""Content-Length: 507 The first line contains a method, a URI and an HTTP version, each separated by one or more blank spaces. The succeeding lines contain more information regarding the web service exchanged. ESB-based integration heavily leverages the HTTP protocol due to its open nature, maturity, and acceptability. We will now look at the support provided by the ServiceMix in using HTTP. ServiceMix's servicemix-http Binding external web services at the ESB layer can be done in multiple ways but the best way is to leverage JBI components such as the servicemix-http component within ServiceMix. We will look in detail at how to bind the web services onto the JBI bus. servicemix-http in Detail servicemix-http is used for HTTP or SOAP binding of services and components into the ServiceMix NMR. For this ServiceMix uses an embedded HTTP server based on the Jetty. The following are the two ServiceMix components: org.apache.servicemix.components.http.HttpInvoker org.apache.servicemix.components.http.HttpConnector As of today, these components are deprecated and the functionality is replaced by the servicemix-http standard JBI component. A few of the features of the servicemix-http are as follows: Supports SOAP 1.1 and 1.2 Supports MIME with attachments Supports SSL Supports WS-Addressing and WS-Security Supports WSDL-based and XBean-based deployments Support for all MEPs as consumers or providers Since servicemix-http can function both as a consumer and a provider, it can effectively replace the previous HttpInvoker and HttpConnector component. Consumer and Provider Roles When we speak of the Consumer and Provider roles for the ServiceMix components, the difference is very subtle at first sight, but very important from a programmer perspective. The following figure shows the Consumer and Provider roles in the ServiceMix ESB: The above figure shows two instances of servicemix-http deployed in the ServiceMix ESB, one in a provider role and the other in the consumer role. As it is evident, these roles are with respect to the NMR of the ESB. In other words, a consumer role implies that the component is a consumer to the NMR whereas a provider role implies the NMR is the consumer to the component. Based on these roles, the NMR will take responsibility of any format or protocol conversions for the interacting components. Let us also introduce two more parties here to make the role of a consumer and a provider clear—a client and a service. In a traditional programming paradigm, the client interacts directly with the server (or service) to avail the functionality. In the ESB model, both the client and the service interact with each other only through the ESB. Hence, the client and the service need peers with their respective roles assigned, which in turn will interact with each other. Thus, the ESB consumer and provider roles can be regarded as the peer roles for the client and the service respectively. Any client request will be delegated to the consumer peer who in turn interacts with the NMR. This is because the client is unaware of the ESB and the NMR protocol or format. However, the servicemix-http consumer knows how to interact with the NMR. Hence any request from the client will be translated by the servicemix-http consumer and delivered to the NMR. On the service side also, the NMR needs to invoke the service. But the server service is neutral of any specific vendor's NMR and doesn't understand the NMR language as such. A peer provider role will help here. The provider receives the request from the NMR, translates it into the actual format or protocol of the server service and invokes the service. Any response will also follow the reverse sequence.

Defining a Service We first need to define a service. Our first service will be named learningFirstService. In the folder ${component:learning}, create a new folder called servicedef. In that folder, create a new file called services.xml and enter into it this: <?xml version="1.0" encoding="UTF-8" ?> <services xsi:noNamespaceSchemaLocation="http://www.ofbiz.org/dtds/services.xsd"> <description>Learning Component Services</description> <service name="learningFirstService" engine="java" location="org.ofbiz.learning.learning.LearningServices" invoke="learningFirstService"> <description>Our First Service</description> <attribute name="firstName" type="String" mode="IN" optional="true"/> <attribute name="lastName" type="String" mode="IN" optional="true"/> </service> </services> In the file ${component:learning}ofbiz-component.xml, add after the last <entity-resource> element this: <service-resource type="model" loader="main" location="service def/services.xml"/> That tells our component learning to look for service definitions in the file ${component:learning}servicedefservices.xml. It is important to note that all service definitions are loaded at startup; therefore any changes to any of the service definition files will require a restart! Creating the Java Code for the Service In the package org.ofbiz.learning.learning, create a new class called LearningServices with one static method learningFirstService: package org.ofbiz.learning.learning; import java.util.Map; import org.ofbiz.service.DispatchContext; import org.ofbiz.service.ServiceUtil; public class LearningServices { public static final String module = LearningServices.class.getName(); public static Map learningFirstService(DispatchContext dctx, Map context){ Map resultMap = ServiceUtil.returnSuccess("You have called on service 'learningFirstService' successfully!"); return resultMap; } } Services must return a map. This map must contain at least one entry. This entry must have the key responseMessage (see org.ofbiz.service.ModelService.RESPONSE_MESSAGE), having a value of one of the following: success or ModelService.RESPOND_SUCCESS error or ModelService.RESPOND_ERROR fail or ModelService.RESPOND_FAIL By using ServiceUtil.returnSuccess() to construct the minimal return map, we do not need to bother adding the responseMessage key and value pair. Another entry that is often used is that with the key successMessage (ModelService.SUCCESS_MESSAGE). By doing ServiceUtil.returnSuccess("Some message"), we will get a return map with entry successMessage of value "Some message". Again, ServiceUtil insulates us from having to learn the convention in key names. Testing Our First Service Stop OFBiz, recompile our learning component and restart OFBiz so that the modified ofbiz-component.xml and the new services.xml can be loaded. In ${component:learning}widgetlearningLearningScreens.xml, insert a new Screen Widget: <screen name="TestFirstService"> <section> <widgets> <section> <condition><if-empty field-name="formTarget"/></condition> <actions> <set field="formTarget" value="TestFirstService"/> <set field="title" value="Testing Our First Service"/> </actions> <widgets/> </section> <decorator-screen name="main-decorator" location="${parameters.mainDecoratorLocation}"> <decorator-section name="body"> <include-form name="TestingServices" location="component://learning/widget/learning/LearningForms.xml"/> <label text="Full Name: ${parameters.fullName}"/> </decorator-section> </decorator-screen> </widgets> </section> </screen> In the file ${component:learning}widgetlearningLearningForms.xml, insert a new Form Widget: <form name="TestingServices" type="single" target="${formTarget}"> <field name="firstName"><text/></field> <field name="lastName"><text/></field> <field name="planetId"><text/></field> <field name="submit"><submit/></field> </form> Notice how the formTarget field is being set in the screen and used in the form. For now don't worry about the Full Name label we are setting from the screen. Our service will eventually set that. In the file ${webapp:learning}WEB-INFcontroller.xml, insert a new request map: <request-map uri="TestFirstService"> <event type="service" invoke="learningFirstService"/> <response name="success" type="view" value="TestFirstService"/> </request-map> The control servlet currently has no way of knowing how to handle an event of type service, so in controller.xml we must add a new handler element immediately under the other <handler> elements: <handler name="service" type="request" class="org.ofbiz.webapp.event.ServiceEventHandler"/> <handler name="service-multi" type="request" class="org.ofbiz.webapp.event.ServiceMultiEventHandler"/> We will cover service-multi services later. Finally add a new view map: <view-map name="TestFirstService" type="screen" page="component://learning/widget/learning/LearningScreens.xml#TestFirstService"/> Fire to webapp learning an http OFBiz request TestFirstService, and see that we have successfully invoked our first service: Service Parameters Just like Java methods, OFBiz services can have input and output parameters and just like Java methods, the parameter types must be declared. Input Parameters (IN) Our first service is defined with two parameters: <attribute name="firstName" type="String" mode="IN" optional="true"/> <attribute name="lastName" type="String" mode="IN" optional="true"/> Any parameters sent to the service by the end-user as form parameters, but not in the services list of declared input parameters, will be dropped. Other parameters are converted to a Map by the framework and passed into our static method as the second parameter. Add a new method handleInputParamaters to our LearningServices class. public static Map handleParameters(DispatchContext dctx, Map context){ String firstName = (String)context.get("firstName"); String lastName = (String)context.get("lastName"); String planetId= (String)context.get("planetId"); String message = "firstName: " + firstName + "<br/>"; message = message + "lastName: " + lastName + "<br/>"; message = message + "planetId: " + planetId; Map resultMap = ServiceUtil.returnSuccess(message); return resultMap; } We can now make our service definition invoke this method instead of the learningFirstService method by opening our services.xml file and replacing: <service name="learningFirstService" engine="java" location="org.ofbiz.learning.learning.LearningServices" invoke="learningFirstService"> with: <service name="learningFirstService" engine="java" location="org.ofbiz.learning.learning.LearningServices" invoke="handleParameters"> Once again shutdown, recompile, and restart OFBiz. Enter for fields First Name, Last Name, and Planet Id values Some, Name, and Earth, respectively. Submit and notice that only the first two parameters went through to the service. Parameter planetId was dropped silently as it was not declared in the service definition. Modify the service learningFirstService in the file ${component:learning}servicedefservices.xml, and add below the second parameter a third one like this: <attribute name="planetId" type="String" mode="IN" optional="true"/> Restart OFBiz and submit the same values for the three form fields, and see all three parameters go through to the service.  

Task Scheduling with Quartz Both people-oriented and system-oriented BPM systems need a mechanism to execute tasks within an event or temporal constraint, for example, every time a state change occurs or every two weeks. BPM suites address these requirements with a job-scheduling component responsible for executing tasks at a given time. OSWorkflow, the core of our open-source BPM solution, doesn't include these temporal capabilities by default. Thus, we can enhance OSWorkflow by adding the features present in the Quartz open-source project. What is Quartz? Quartz is a Java job-scheduling system capable of scheduling and executing jobs in a very flexible manner. The latest stable Quartz version is 1.6. You can download Quartz from http://www.opensymphony.com/quartz/download.action. Installing The only file you need in order to use Quartz out of the box is quartz.jar. It contains everything you need for basic usage. Quartz configuration is in the quartz. properties file, which you must put in your application's classpath. Basic Concepts The Quartz API is very simple and easy to use. The first concept that you need to be familiar with is the scheduler. The scheduler is the most important part of Quartz, managing as the word implies the scheduling and unscheduling of jobs and the firing of triggers. Task Scheduling with Quartz A job is a Java class containing the task to be executed and the trigger is the temporal specification of when to execute the job. A job is associated with one or more triggers and when a trigger fires, it executes all its related jobs. That's all you need to know to execute our Hello World job. Integration with OSWorkflow By complementing the features of OSWorkflow with the temporal capabilities of Quartz, our open-source BPM solution greatly enhances its usefulness. The Quartz-OSWorkflow integration can be done in two ways—Quartz calling OSWorkflow workflow instances and OSWorkflow scheduling and unscheduling Quartz jobs. We will cover the former first, by using trigger-functions, and the latter with the ScheduleJob function provider. Creating a Custom Job Job's are built by implementing the org.quartz.Job interface as follows: public void execute(JobExecutionContext context) throws JobExecutionException; The interface is very simple and concise, with just one method to be implemented. The Scheduler will invoke the execute method when the trigger associated with the job fires. The JobExecutionContext object passed as an argument has all the context and environment data for the job, such as the JobDataMap. The JobDataMap is very similar to a Java map but provides strongly typed put and get methods. This JobDataMap is set in the JobDetail file before scheduling the job and can be retrieved later during the execution of the job via the JobExecutionContext's getJobDetail().getJobDataMap() method. Trigger Functions trigger-functions are a special type of OSWorkflow function designed specifically for job scheduling and external triggering. These functions are executed when the Quartz trigger fires, thus the name. trigger-functions are not associated with an action and they have a unique ID. You shouldn't execute a trigger-function in your code. To define a trigger-function in the definition, put the trigger-functions declaration before the initial-actions element. ... <trigger-functions> <trigger-function id="10"> <function type="beanshell"> <arg name="script"> propertySet.setString("triggered", "true"); </arg> </function> </trigger-function> </trigger-functions> <initial-actions> ... This XML definition fragment declares a trigger-function (having an ID of 10), which executes a beanshell script. This script will put a named property inside the PropertySet of the instance but you can define a trigger-function just like any other Java- or BeanShell-based function. To invoke this trigger-function, you will need an OSWorkflow built-in function provider to execute trigger-functions and to schedule a custom job—the ScheduleJob FunctionProvider. More about Triggers Quartz's triggers are of two types—the SimpleTrigger and the CronTrigger. The former, as its name implies, serves for very simple purposes while the latter is more complex and powerful; it allows for unlimited flexibility for specifying time periods. SimpleTrigger SimpleTrigger is more suited for job firing at specific points in time, such as Saturday 1st at 3.00 PM, or at an exact point in time repeating the triggering at fixed intervals. The properties for this trigger are the shown in the following table: s. The properties for this trigger are the shown in the following table: Property Description Start time The fire time of the trigger. End time The end time of the trigger. If it is specified, then it overrides the repeat count. Repeat interval The interval time between repetitions. It can be 0 or a positive integer. If it is 0, then the repeat count will happen in parallel. Repeat count How many times the trigger will fire. It can be 0, a positive integer, or SimpleTrigger.REPEAT_INDEFINITELY.     CronTrigger The CronTrigger is based on the concept of the UN*X Cron utility. It lets you specify complex schedules, like every Wednesday at 5.00 AM, or every twenty minutes, or every 5 seconds on Monday. Like the SimpleTrigger, the CronTrigger has a start time property and an optional end time. A CronExpression is made of seven parts, each representing a time component: Each number represents a time part: 1 represents seconds 2 represents minutes 3 represents hours 4 represents the day-of-month 5 represents month 6 represents the day-of-week 7 represents year (optional field) Here are a couple of examples of cron expression: 0 0 6 ? * MON: This CronExpression means "Every Monday at 6 AM". 0 0 6 * *: This CronExpression mans "Every day at 6 am". For more information about CronExpressions refer to the following website: http://www.opensymphony.com/quartz/wikidocs/CronTriggers%20Tutorial.html. Scheduling a Job We will get a first taste of Quartz, by executing a very simple job. The following snippet of code shows how easy it is to schedule a job.     SchedulerFactory schedFact = new                                             org.quartz.impl.StdSchedulerFactory();     Scheduler sched = schedFact.getScheduler();     sched.start();        JobDetail jobDetail = new JobDetail("myJob", null, HelloJob.class);        Trigger trigger = TriggerUtils.makeHourlyTrigger();                                                       // fire every hour        trigger.setStartTime(TriggerUtils.getEvenHourDate(new Date()));                                                     // start on the next even hour        trigger.setName("myTrigger");        sched.scheduleJob(jobDetail, trigger); The following code assumes a HelloJob class exists. It is a very simple class that implements the job interface and just prints a message to the console. package packtpub.osw; import org.quartz.Job; import org.quartz.JobExecutionContext; import org.quartz.JobExecutionException; /** * Hello world job. */ public class HelloJob implements Job { public void execute(JobExecutionContext ctx) throws JobExecutionException { System.out.println("Hello Quartz world."); } }   The first three lines of the following code create a SchedulerFactory, an object that creates Schedulers, and then proceed to create and start a new Scheduler. SchedulerFactory schedFact = new org.quartz.impl.StdSchedulerFactory(); Scheduler sched = schedFact.getScheduler(); sched.start(); This Scheduler will fire the trigger and subsequently the jobs associated with the trigger. After creating the Scheduler, we must create a JobDetail object that contains information about the job to be executed, the job group to which it belongs, and other administrative data. JobDetail jobDetail = new JobDetail("myJob", null, HelloJob.class); This JobDetail tells the Scheduler to instantiate a HelloJob object when appropriate, has a null JobGroup, and has a Job name of "myJob". After defining the JobDetail, we must create and define the Trigger, that is, when the Job will be executed and how many times, etc. Trigger trigger = TriggerUtils.makeHourlyTrigger(); // fire every hour trigger.setStartTime(TriggerUtils.getEvenHourDate(new Date())); // start on the next even hour trigger.setName("myTrigger"); The TriggerUtils is a helper object used to simplify the trigger code. With the help of the TriggerUtils, we will create a trigger that will fire every hour. This trigger will start firing the next even hour after the trigger is registered with the Scheduler. The last line of code puts a name to the trigger for housekeeping purposes. Finally, the last line of code associates the trigger with the job and puts them under the control of the Scheduler. sched.scheduleJob(jobDetail, trigger); When the next even hour arrives after this line of code is executed, the Scheduler will fire the trigger and it will execute the job by reading the JobDetail and instantiating the HelloJob.class. This requires that the class implementing the job interface must have a no-arguments constructor. An alternative method is to use an XML file for declaring the jobs and triggers. This will not be covered in the book, but you can find more information about it in the Quartz documentation. Scheduling from a Workflow Definition The ScheduleJob FunctionProvider has two modes of operation, depending on whether you specify the jobClass parameter or not. If you declare the jobClass parameter, ScheduleJob will create a JobDetail with jobClass as the class implementing the job interface. <pre-functions> <function type="class"> <arg name="class.name">com.opensymphony.workflow.util.ScheduleJob </arg> <arg name="jobName">Scheduler Test </arg> <arg name="triggerName">SchedulerTestTrigger</arg> <arg name="triggerId">10 </arg> <arg name="jobClass">packtpub.osw.SendMailIfActive </arg> <arg name="schedulerStart">true </arg> <arg name="local">true </arg> </function> </pre-functions> This fragment will schedule a job based on the SendMailIfActive class with the current time as the start time. The ScheduleJob like any FunctionProvider can be declared as a pre or a post function. On the other hand, if you don't declare the jobClass, ScheduleJob will use the WorkflowJob.class as the class implementing the job interface. This job executes a trigger-function on the instance that scheduled it when fired.    <pre-functions> <function type="class"> <arg name="class.name">com.opensymphony.workflow.util.ScheduleJob </arg> <arg name="jobName">Scheduler Test </arg> <arg name="triggerName">SchedulerTestTrigger </arg> <arg name="triggerId">10 </arg> <arg name="schedulerStart">true </arg> <arg name="local">true </arg> </function> </pre-functions>   This definition fragment will execute the trigger-function with ID 10 as soon as possible, because no CronExpression or start time arguments have been specified. This FunctionProvider has the arguments shown in the following table:

Who Should Read This Read on if you are new to change control, or believe that change control only applies to software, or that it is only meant for large projects. If you are a software pro working with large software projects, you can still read this if you want a gentle introduction to Subversion or svn as it is called. Introduction We have all heard those trite remarks about change -- “... change is the only constant ...”, or similar ones, especially before an unpleasant corporate announcement. These overused remarks about change are unfortunately true. During the course of a day, we make numerous (hopefully!) interrelated changes, updates, or transformations to our work products to reach specific project goals. Needless to say, these changes need to be tracked along with the rationale behind each if we are to prevent ourselves from repeating mistakes, or simply want to recall why we did what we did one month ago! Note that we are not talking about only code or documents here; your work products could be a portfolios of photographs, animations, or some arbitrary binary format. A change control discipline also gives you additional advantages such as being able to develop simultaneous versions of work products for different purposes or clients, rolling back to a previous arbitrary version, or setting up trial development in a so-called branch to bring it back to the main work stream after due review. You also have a running history of how your work product has evolved over time and features. Fetching from a change managed repository also prevents you from creating those fancifully named multiple copies of a file just to keep track of its versions. To reiterate: we use the words 'work product' and 'development' in the broadest sense and not just as applied to software. You might as well be creating a banner ad for your client as much as a Firefox plugin. In the rest of this article we will see how to build a simple personal change control discipline for your day-to-day work using a version control tool. As you will note, 'control' and 'management' have been used interchangeably, though a little hair splitting will yield rich dividends in terms of how different these terms are. Subversion Subversion is version control system available on the Linux (and similar) platforms. If you are trapped in a proprietary world by choice, circumstance, or compulsion, you should try TortoiseSVN. Here, we confine ourselves to the Linux platform. Subversion works by creating a time line of your work products from their inception (or from the point they are brought under version control) to the present point in time, by capturing snapshots of your work products at discrete points that you decide. Each snapshot is a version. You can traverse this time line and extract specific versions for use. How does subversion do it? It versions entire directories. A new version of your directory will be created even if you change one file in it. Don't worry; this does not lead to an explosion of file size with each version. Explaining some terminology, albeit informally, should make the going easier from here. Subversion stores your project(s) in a repository. For the purpose of this article, our repository will stay on the local machine. A revision is nothing but a particular snapshot of the project directory. A working directory is your sandbox. This is where you check out a particular version of your project directory from the repository, make any modifications to it, and then do a check in back into the repository. Revision numbers are bumped up with each check in. You can revert a configuration item, which is like undoing any changes you made. If all this sounds a little abstruse, don't worry, because we will shortly set up our repository so that you can try things out. A commit is when you...., well commit a change done to a file into the repository. Subversion is mostly bundled with a Linux distribution. Find out if you have yours with a 'man svn' or 'svn -h' or a 'whereis svn' command. Setting up Your Repository You can set up your repository in your home directory if you are working on a shared environment. If you have a machine to yourself, you might want to create an 'svn' account with /sbin/nologin (politely refuses logins) as the shell. Your repository might then be '/home/svn/repos'. Subversion is a command line tool. But the only command you will ever issue for the purpose of this article will be to set up your repository: $ svnadmin create /path/to/your/repository The rest, as they say, is GUI! Let Us Get Visual A GUI for subversion is a great tool for learning and working even if you decide to settle for the command line once you get more proficient. eSvn (http://zoneit.free.fr/esvn/) is a Qt-based graphical front end for Subversion. Follow the instructions with the download to compile and install eSvn. Run esvn and this is how it will look with the File | Options... dialog open. Make sure you enter the correct path to svn if not for the other items.