How-To Tutorials

Working with Mail Portlet For the purpose of this article, we will use an intranet website called book.com  which is created  for a fictions company named "Palm Tree Publications". In order to let employees manage their emails, we can use the Liferay Mail portlet. As an administrator of "Palm Tree Publications", you need to create a Page called "Mail" under the Page, "Community" at the Book Lovers Community Public Pages and also add the Mail portlet in the Page, "Mail". Experiencing Mail Management First of all, login as "Palm Tree". Then, let's do the above as follows: Add a Page called "Mail" under the Page "Community" at the Book Lovers Community Public Pages, if the Page is not already present. If the Mail portlet is not already present, add it in the Page, "Mail" of the Book Lovers Community where you want to manage mails. You will see the Mail portlet as shown in the following figure. Let's assume that we set up the mail domain as "cignex.com" in the Enterprise Admin portlet for testing purposes, as we have a mail engine with this mail domain already. Of course, you could set up the mail domain as "book.com", or something else, if you had a mail engine with this mail domain in your hand. As an editor of the editorial department, "Lotti Stein", you may want to manage your mails in the mail domain, "cignex.com". You can first choose a user name for your personal company the email address, say "admin1234" and register. Let's do it as follows: Login as "Lotti Stein". Go to the Page "Mail" under the Page, "Community", at the Book Lovers community Public Pages. Locate the Mail portlet. Input the value for User name as "admin1234". Click the Register button. Your new email address is "admin1234@cignex.com". This email address will also serve as your login, as shown in the following figure. You can now check for new messages in your inbox, by clicking the Inbox link first. Then, you can view the Unread messages, and either Check Mail or create a New mail, as shown in the following figure: You can go to the Page of Mail management by clicking on any link of Unread Messages, or Check Mail button or New button. Further, you can manage emails through the Mail portlet of your current account. Email management includes the following features (as shown in the following figure): Create a New email. Check Mail. Reply to an email. Reply All emails. Forward emails. Delete emails. Print emails, and Search. Note that the first email with the subject, "Users in Staging server", is sent through the SMS Text Messenger portlet. For more details, refer to the forthcoming section. How to Set up Mail Server? In order to make the Mail portlet work, we have to set up a mail server with IMAP, POP and SMTP protocols. Suppose that the Enterprise "Palm Tree Publications" has a mail server with the domain "exg3.exghost.com", an account "admin@cignex.com/admin1234", and protocol IMAP, POP and SMTP. As an administrator, you need to integrate this mail server with IMAP, POP and SMTP protocol in Liferay. Let's do it as follows: Find the file ROOT.xml in $TOMCAT_DIR/conf/Catalina/localhost. Find the mail configuration first. Then configure it as follows: <!-- Mail --><Resourcename="mail/MailSession"auth="Container"type="javax.mail.Session"mail.imap.host="exg3.exghost.com"mail.imap.port="143"mail.pop.host="exg3.exghost.com"mail.pop.port="110"mail.store.protocol="imap"mail.transport.protocol="smtp"mail.smtp.host="exg3.exghost.com"mail.smtp.port="2525"mail.smtp.auth="true"mail.smtp.starttls.enable="true"mail.smtp.user="admin@cignex.com"password="admin1234"mail.smtp.socketFactory.class="javax.net.ssl.SSLSocketFactory"/> In short, a Mail portlet is an AJAX web-mail client. We can configure it to work with any mail server. It reduces page refreshes, since it displays message previews and message lists in a dual pane window. How to Set up Mail Portlet? If you have proper Permissions, you can change the preferences of the Mail portlet. To change the preferences, you can simply click the Preferences icon to the upper right of the Mail portlet. With the Recipients tab selected, you can find potential recipients from the Directory (Enabled or Disabled) and the Organization (My Organization or All Available). Click the Save button after making any changes. Using the Filters tab, you can set the values to filter emails associated with an email address to a Folder. Click the Save button after making any changes. Note that the maximum number of email addresses is ten. This number is also configurable at the portal-ext.properties Similarly, the Forward Address tab allows all emails to be forwarded to the email address you want. Enter one email address Per Line. Remove all entries to disable email forwarding. Select Yes to leave, or No to not leave a copy of the forwarded message. Click the Save button after making any changes. Further, the Signature tab also allows you to set up your signature using HTML text editor. The signature you have set up will be added to each outgoing message. Click the Save button after making any changes. The Vacation Message tab allows you to set up vacation messages using HTML text editor. The vacation message notifies others of your absence (as shown in the following figure). Click the Save button after making any changes.

Basic DOJO 123 accordion In my earlier article I had used the version of the Toolkit which had the accordion in the Widgets. In the latest version which I am using, the accordion is found in digit/layout. The code is similar to that in the earlier article. Basically you create a accordion container and then place the accordion panes inside the container. In referencing the Dojo library I am using part of the references from the Dojo Toolkit 123 installed on my local IIS and part of the reference from the AOL site (uses the 1.0.0 script). Listing 1: AccordionOrig.htm: A basic accordion with three panes [DOJO 123] <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Accordion Pane with jQueries</title> <style type="text/css"> @import "http://localhost/Dojo123/dojo123/dijit/themes/tundra/tundra.css"; @import "http://localhost/Dojo123/dojo123/dojo/resources/dojo.css" </style> <script type="text/javascript" src="http://o.aolcdn.com/dojo/1.0.0/dojo/dojo.xd.js" djConfig="parseOnLoad: true"></script> <script type="text/javascript"> dojo.require("dojo.parser"); dojo.require("dijit.layout.AccordionContainer"); </script> </head> <body class="tundra"> <div dojoType="dijit.layout.AccordionContainer" duration="200" style="margin-right: 30px; width: 400px; height: 400px; overflow: scroll"> <!--Pane 1 --> <div dojoType="dijit.layout.AccordionPane" selected="true" title="Page 1" style="color:red;overflow: scroll; background-color:#FFFF80;"> <!--Pane 1 content--> <p >Test 1</a></p > </div> <!--Pane 2 --> <div dojoType="dijit.layout.AccordionPane" title="Page 2" style="overflow: scroll;background-color:#FFFF80;"> <!--Pane 2 content--> <p >Test 2</p > </div> <!-- Pane 3--> <div dojoType="dijit.layout.AccordionPane" title="Page 3" style="color:magenta;overflow: scroll;background-color:#FFFF80;"> <!--Pane 3 content--> <p >Test 3</a></p > </div> </div> </body> </html> This page when browsed to, will display the accordion as shown in Figure 1. This was cross-browser compatible in the following browsers: IE 6.0, Opera 9.1, Firefox 3.0.5, and Safari 3.2.1. The page did not render correctly (all panes completely open) in Google Chrome 1.0.154.43. Figure 1 jQuery API Components used in the article jQuery 1.3 downloaded from this site is used as a source for the script. From the API reference only two simple components were chosen to be embedded in the panes - the Selector and the Effects. The slideUp() effect where in, when you click on the code sensitive area the region of the area on the web page slides up. H1 Selector styled using jQuery Using jQuery you can selectively apply style to tags, ids, etc. In the example shown in the code that follows the H1 tag is styled using jQuery. Listing 2: H1SelectorJQry.htm: Tag styling with jQuery <html> <head></head> <body> <script language="JavaScript" src="http://localhost/JayQuery/jquery-1.3.min.js"> </script> <h1>Jquery inside a DOJO Accordion Pane</h1> <script type="text/JavaScript"> $(document).ready(function(){ $("h1").css("color", "magenta");}); </script> </body> <html> In the above, the jQuery code (inside the script tags) renders the h1 tag in the color shown as in Figure 2. Figure 2 jQuery Effect: slideUp() The htm page with the listing 3 when browsed to, displays a pale green 300 x 300 square corresponding to the styling of the p tag as shown in Figure 4. When clicked anywhere inside this square, the square slides up and disappears. This is the slideUp() effect. Listing 3: p_slideUp.htm: Jquery Effect <html> <head></head> <body> <script language="JavaScript" src="http://localhost/JayQuery/jquery-1.3.min.js"> </script> <div><p style="width:300; height:300; background-color:palegreen; color:darkgreen;">Test</p></div> <script type="text/JavaScript"> $("p").click(function () { $(this).slideUp(); }); </script> </body> <html> This page gets displayed as shown in Figure 3. When you click anywhere in the pale green area the "P" region slides up. Figure 3

There's lots what Nagios can do, and how it can make your life easier. Imagine that you set up Nagios to send a text message to your mobile during day time. It can also send you a message on Jabber or MSN. Imagine that you also make Nagios stop notifying you when your workstation is not online. Even though the above examples above seem complicated, they are actually quite simple to implement. It's a matter of combining event handlers with custom variables, and a little ingenuity. A service that will check if a user's workstation is present can have an event handler to automatically enable and disable host and/or service notifications for a contact or contact group. It's also possible to set up your monitoring to notify managers if the issue has not been fixed within a certain period of time. Based on the importance of a host or service, these can be different managers that are notified and different time periods after which the notification is sent. Nagios can also be used to notify emergency response teams, so that if a problem is not fixed in a short period of time, they will assist in recovering from the potential after effects of this problem. There are cases when you want Nagios to perform one or more actions if a service starts or stops malfunctioning. For instance, you might have a web server set up to retry five times before a failure becomes a hard state for Nagios. In such a case, you can also configure Nagios to try restarting itself after the third soft failure —if it fails, it will move to a hard state after the next two failures. In case the restart succeeds, a hard state will not even get recorded and only a soft failure will get logged. Nagios is able to integrate itself with other applications that can send commands to Nagios directly and can report the status of host or service checks. Sending commands can be used by Nagios web interface, but you might as well use it inside your application or event handlers for various objects. Effective Notifications This section covers notifications in depth and describes the details of how Nagios can tell other people about what is happening. We will discuss a simple approach, as well as a more complex approach on how notifications can make your life easier. Probably, most people already know that a plain email notification about a problem may not always be the right thing to do. As people's inboxes get cluttered with emails, the usual approach is to create rules to move certain messages that they don't even look at to separate folders. There's a pretty good chance that if people start getting a lot of notifications that they won't need to react to, they'll simply ask their favorite mailing program to move these messages into a 'do not look in here unless you have plenty of time' folder. Moreover, in such cases, if there is an issue they should be handling, they will most probably not even see the notification email. This section talks about the things that can be implemented in your company to make notifications more convenient to the IT staff. Limiting the amount of irrelevant information sent to various people tends to increase their response time, as they will have much less information to filter out. At this point, it's worth mentioning that there's another easy solution. Again, most people do not use it even though it offers a very flexible set up in an easy way. The approach is to create multiple contacts for a single person. For example, you can set up different contacts when you're at work, when you're offline, and define a profile to not to disturb you too much during the night. The first issue that many Nagios administrators overlook is the ability to create more than one notification command. In this way, Nagios can try to notify you on both instant messaging (such as Jabber, Gtalk, MSN, or Yahoo) and email. It can also send you an SMS. A disadvantage is that at some point, you might end up receiving SMSes at 2 AM about an outage of a machine that may well be down for the next 3days and is not critical. For example you can set up the following contacts to handle various times of the day in a different fashion: jdoe-workhours would be a contact that will only receive notifications during working hours; notifications will be carried out using both the corporate IM system and an email jdoe-daytime would be a contact that will only receive notifications between 7 AM and 10 PM, excluding working hours; notifications will be sent as a text or a pager message, and an email jdoe-night would be a contact that will only receive notifications between 10 PM and 7 AM; notifications will only be sent out as an email All entries would also contain contactgroups pointing to the same groups that the single jdoe contact entry used to contain. This way, the other objects such as hosts, services, or contact groups related to this user would not be affected. All entries would also reside in the same file; for example, contacts/jdoe.cfg. The main drawback of this approach is that logging on to the web interface would require using one of the users above or keeping the jdoe contact without any notifications, just to be able to log on to the interface. The example above combined both the creation of multiple contacts and use of multiple notification commands to achieve a convenient way of getting notified about a problem. Using only multiple contacts also works fine. Another approach to the problem is to define different contacts for different ways of being notified—for example, jdoe-email, jdoe-sms, and jdoe-jabber. This way, you can define different contact methods for various time periods—instant messages during working hours, SMSes while on duty, and an email when not at work. Another important issue is to make sure that as few people as possible are notified of the problem. Imagine there is a host without an explicit administrator assigned to it. A notification about a problem gets sent out to 20 different people. In such a case, either each of them will assume that someone else will resolve the problem, or people will run into a communication problem over discussing who will actually handle it. Teams that cooperate tightly with each other usually solve these issues naturally—knowledgeable people start discussing a solution and a natural person to solve the issue comes out of the discussion. However, the teams that are distributed across various locations or that have poor communication skills will run into problems in such cases. This is why, it is a good idea to either nominate a coordinator who will assign tasks as they arise, or try to maintain a short list of people responsible for each machine. If you need to make sure that other people will investigate the problem if the original owner of the machine cannot do it immediately, then it is a good idea to use escalations for this purpose. These are described later in this article. Previously, we mentioned that notifications only via email may not always be the best thing to do. For example, they don't work well for situations that require fast response times. There are various reasons behind this. Firstly, emails are slow—even though the email lands on your mail server in a few seconds, people usually only poll their emails every few minutes. Secondly, people tend to filter emails and skip those that they are not interested in. Another good reason why emails should not always be used is that they stay on your email account until you actually fetch and read them. If you have been on a 2-week vacation and a problem has occurred, should you still be worried when you read it after you get back? Has the issue been resolved already? If your team needs to react to problems promptly, using email as the basic notification method is definitely not the best choice. Let's consider what other possibilities exist to notify users of a problem effectively. As already mentioned, a very good choice is to use instant messaging or SMS (Simple Messaging Service) messages as the basic means of notification, and only use email as a last resort. Some companies might also use the client-server approach to notify the users of the problems, perhaps integrated with showing Nagios' status only for particular hosts and services. NagiosExchange has plenty of available solutions you can use for handling notifications effectively. The first and the most powerful option is to use Jabber for notifications. There is an existing script for this that is available in the contributions repository on the Nagios project website. This is a small Perl script that sends messages over Jabber. You may need to install additional system packages to handle Jabber connectivity from Perl. On Ubuntu, this requires running the following command: root@ubuntu1:~# apt-get install libnet-jabber-perl If you are using CPAN to install Perl packages, then simply run the following command: root@ubuntu1:~# cpan install Net::Jabber In order to use the notification plugin, you will need to customize the script—change the SERVER, PORT, USER, and PASSWORD parameters to an existing account. Our recommendation is to create a separate account to use only for Nagios notifications—you will need to set up authorization for each user that you want to send notifications to. As you plan to monitor servers and potentially even outgoing Internet connectivity, it would not be wise to use public Jabber servers for reporting errors. Therefore, it would be a good idea to set up a private Jabber server, probably on the same host on which the Nagios monitoring system is running. If you plan to have a more comfortable setup, you can also use Tkabber as a Jabber client, and write a plugin that reads object's cache and the current status from the Nagios host and shows an up-to-date report for hosts that you are the owner of. Information on reading Nagios output can be found on my Tclmentor blog Another possibility is to send messages over SMB/CIFS protocol. This way, you can send messages directly to the computers, assuming people are running the Microsoft Windows operating system. There is also the possibility of receiving messages using Samba package on UNIX machines. This requires having the smbclient command installed. On Ubuntu, this requires running the following command: root@ubuntu1:~# apt-get install smbclient A simple command definition example that uses smbclient directly to send messages to the specified host name is as follows: define command{command_name notify_host_via_smbclientcommand_line printf "Host notification: $NOTIFICATIONTYPE$nnHost: $HOSTNAME$nState: $HOSTSTATE$Address: $HOSTADDRESS$nInfo: $HOSTOUTPUT$" |smbclient -M $_CONTACTSMBHOSTNAME$} The preceding example uses the $_CONTACTSMBHOSTNAME$ macro definition. It maps to the _SMBHOSTNAME custom variable defined for a specified contact. In order for Windows XP and 2003 to show the messages from other users correctly, you will need to enable the Messenger service. This can be done by running the following command as the system administrator, or as a user with administrator privileges: C> net start Messenger Another way to communicate problems to the users is to use text messages, also known as SMS. This is a very sensitive issue because if your system is not properly configured, it can send a message in the middle of a night about a noncritical thing that can be fixed within the next 5 working days. There is a very useful package for handling of SMS sending called SMSServerTools. It allows the configuration of email and web gateways, as well as sending text messages over dedicated GSM (Global System for Mobile Communication) terminals. The tool offers the ability to queue text messages so that it handles a higher number of messages to be sent by the appropriate means. GSM terminals work in a manner similar to a typical mobile phone. They use a standard SIM card and have a normal GSM phone module that is used to send SMS messages. Terminals are usually connected via a serial port or USB connection. Your server can then send messages by sending commands to the terminal. GSM terminals use the same command convention as phone modems, although each model uses a different set of commands. For information on how you can send SMS messages over it, please refer the terminal's user manual. Current mobile phones also offer cheap Internet connectivity, and smart devices offer the possibility to write custom applications in Java, .NET, and many other languages including Python and Tcl. Therefore, you can also make a client-server application that queries the server for the status of selected hosts and services. It can even be unified with a notification command that pushes the changes down to the application immediately. These are only a few of the possibilities that you can use to communicate problems more effectively. Other possibilities include a ready-to-use client-server application (visit http://www.nagiosexchange.org/Notifications.35.0.html?tx_netnagext_pi1[p_view]=182) that allows the sending of notifications to people directly to their desktop machines. One interesting notification command allows you to choose other commands to use based on user availability on Jabber—this sends messages over Jabber if the user is are available and uses SMSes or emails otherwise. (Visit http://www.nagiosexchange.org/Notifications.35.0.html?&tx_netnagext_pi1[p_view]=1036). There are also tools to send messages to ICQ users and ones that use VoIP technology to provide you with predefined wave messages or output from a speech synthesis system. Escalations A common problem with resolving problems is that a host or a service may have blurred ownership. Often, there is no single person responsible for a host or service, which makes things harder. It is also typical to have a service with subtle dependencies on other things, which by themselves are small enough not to be monitored by Nagios. In such a case, it is good to include lower management in the escalations so that they are able to focus on problems that haven't been resolved in a timely manner. Here is a good example: a database server might fail because a small Perl script that is run prior to actual start and clean things up has entered an infinite loop. The owner of this machine gets notified. But the question is who should be fixing it? Should it be the script owner? Or perhaps, should it be the database administrator? In IT reality, this often ends up in a series of throwing ball into each other's yards without solving anything. In such cases, escalations are a great way to solve such complex problems. In the previous example, if the problem is not been resolved after two hours, the IT team coordinator or manager would be notified. Another hour later, he would get another email. At that point, he would schedule an urgent meeting with the developer who owns the script, and the database admin, to discuss how this could be solved. Of course, in real-world scenarios, escalating to management alone would not solve all problems. However, often, situations need a coordinator that will take care of communicating issues between teams and trying to find a company-wide solution. Business-critical services also require much higher attention. In such cases, it is a real benefit for the company if it has an escalation ladder that can be followed for all major problems. Nagios offers many ways to set up escalations, depending on your needs. Escalations do not need to be sent out just after a problem occurs—that would create confusion and prevent smaller problems from being solved. Usually, escalations are set up so that additional people are informed only if a problem has not been resolved after a certain amount of time. From a configuration point of view, all escalations are defined as separate objects. There are two types of objects—hostescalation and serviceescalation. Escalations are configured so that they start and stop being active along with the normal host or service notifications. This way, if you change the notification_ interval directive in host or service definition, the times at which escalations start and stop will also change. A sample escalation for company's main router is as follows: define hostescalation{host_name mainroutercontactgroups it-managementfirst_notification 2last_notification 0notification_interval 60escalation_options d,u,r} The following table describes all available directives for defining a host escalation. Items in bold are required when specifying an escalation. Option Description host_name Defines host names that escalation should be defined for; separated by comma hostgroup_name Defines host group names for all members of which groups escalation should be defined for; separated by comma contacts List of all contacts that should receive notifications related to this escalation; separated by comma; at least one contact or contact group needs to be specified for each escalation contactgroups List of all contacts groups that should receive notifications related to this escalation, separated by comma; at least one contact or contact group needs to be specified for each escalation first_notification Number of notifications after which this escalation becomes active; setting this to 0 causes notifications to be sent until host recovers from problem; see description below last_notification Number of notifications after which this escalation stop being active; see description below notification_interval Specifies number of minutes between sending notifications related to this escalation escalation_period Specifies time period during which escalation should be valid; if not specified defaults to 24 hours a day 7 days a week escalation_options Specifies which notification types for host states should be sent, separated by comma; should be one or more of the following: d - host DOWN state u - host UNREACHABLE state r - host recovery (UP state) Service escalations are defined in a very similar way to host escalations. You can specify one or more hosts or host groups, as well as a single service description. Service escalation will be associated with this service on all hosts mentioned in the host_name and hostgroup_name attributes. The following is an example of a service escalation for an OpenVPN check on the company's main router: define serviceescalation{host_name mainrouterservice_description OpenVPNcontactgroups it-managementfirst_notification 2last_notification 0notification_interval 60escalation_options w,c,r} The following table describes all available directives for defining a service escalation. Items in bold are required when specifying an escalation.

Using dialog animations The dialog provides us with built-in effect abilities and also allows us to specify effects to use when the dialog is opened or closed. Using these effects is extremely easy and gives a great visual flair. Let's look at how these effects can be enabled. Create the following new page: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html lang="en"> <head> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.dialog.css"> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.resizable.css"> <link rel="stylesheet" type="text/css" href="styles/dialogTheme.css"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>jQuery UI Dialog Example 6</title> </head> <body> <div id="myDialog" class="flora" title="This is the title">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean sollicitudin. Sed interdum pulvinar justo. Nam iaculis volutpat ligula. Integer vitae felis quis diam laoreet ullamcorper. Etiam tincidunt est vitae est. Ut posuere, mauris at sodales rutrum, turpis tellus fermentum metus, ut bibendum velit enim eu lectus. Suspendisse potenti. Donec at dolor ac metus pharetra aliquam. Suspendisse purus. Fusce tempor ultrices libero. Sed quis nunc. Pellentesque tincidunt viverra felis. Integer elit mauris, egestas ultricies, gravida vitae, feugiat a, tellus.</div> <script type="text/javascript" src="jqueryui1.6rc2/jquery-1.2.6.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.core.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.dialog.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.resizable.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.draggable.js"></script> <script type="text/javascript"> //define function to be executed on document ready $(function(){ //define config object var dialogOpts = { hide: true }; //create the dialog $("#myDialog").dialog(dialogOpts); }); </script> </body></html> Save this as dialog6.html. In this example, our configuration object contains just one property—the hide property. The hide property accepts the boolean true as its value. This enables the built-in hide effect, which gradually reduces the dialog's size and opacity until it gracefully disappears. We can also enable the show effect, which is the opposite of the hide animation. However, at this stage in the component's development, this causes a slight issue with its display. The following screenshot shows the hide effect in progress: Controlling a dialog programmatically The dialog requires few methods in order to function. As implementers, we can easily open, close, or destroy the dialog at will. The full list of methods we can call on a dialog instance are as follows: Method Used to close Closes or hides the dialog destroy Permanently disables the dialog isOpen Determines whether a dialog is open or not moveToTop Moves the specified dialog to the top of the stack open Opens the dialog Let's look at opening and closing the widget, which can be achieved with the simple use of the open and close methods. Create the following new page in your text editor: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html lang="en"> <head> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.dialog.css"> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.resizable.css"> <link rel="stylesheet" type="text/css" href="styles/dialogTheme.css"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>jQuery UI Dialog Example 7</title> </head> <body> <div id="myDialog" class="flora" title="This is the title"> Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean sollicitudin. Sed interdum pulvinar justo. Nam iaculis volutpat ligula. Integer vitae felis quis diam laoreet ullamcorper. Etiam tincidunt est vitae est. Ut posuere, mauris at sodales rutrum, turpis tellus fermentum metus, ut bibendum velit enim eu lectus. Suspendisse potenti. Donec at dolor ac metus pharetra aliquam. Suspendisse purus. Fusce tempor ultrices libero. Sed quis nunc. Pellentesque tincidunt viverra felis. Integer elit mauris, egestas ultricies, gravida vitae, feugiat a, tellus.</div> <button id="openDialog">Open the Dialog!</button> <script type="text/javascript" src="jqueryui1.6rc2/jquery-1.2.6.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.core.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.dialog.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.resizable.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.draggable.js"></script> <script type="text/javascript"> //define function to be executed on document ready $(function(){ //define doOk function var doOk = function() { //close the dialog $("#myDialog").dialog("close"); } //define config object var dialogOpts = { modal: true, overlay: { background: "url(img/modal.png) repeat" }, buttons: { "Ok!": doOk }, height: "400px", autoOpen: false }; //create the dialog $("#myDialog").dialog(dialogOpts); //define click handler for the button $("#openDialog").click(function() { //open the dialog $("#myDialog").dialog("open"); }); }); </script> </body></html> The open and close methods require no additional arguments and do exactly as they say, pure and simple. Save the file as dialog7.html. The destroy method for a dialog works in a slightly different way than it does for the other widgets we've seen so far. Instead of returning the underlying HTML to its original state, the dialog's destroy method completely disables the widget, hiding its content in the process. Change dialog7.html to make use of the destroy method: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html lang="en"> <head> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.dialog.css"> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.resizable.css"> <link rel="stylesheet" type="text/css" href="styles/dialogTheme.css"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>jQuery UI Dialog Example 8</title> </head> <body> <div id="myDialog" class="flora" title="This is the title"> Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean sollicitudin. Sed interdum pulvinar justo. Nam iaculis volutpat ligula. Integer vitae felis quis diam laoreet ullamcorper. Etiam tincidunt est vitae est. Ut posuere, mauris at sodales rutrum, turpis tellus fermentum metus, ut bibendum velit enim eu lectus. Suspendisse potenti. Donec at dolor ac metus pharetra aliquam. Suspendisse purus. Fusce tempor ultrices libero. Sed quis nunc. Pellentesque tincidunt viverra felis. Integer elit mauris, egestas ultricies, gravida vitae, feugiat a, tellus.</div> <button id="openDialog">Open the Dialog!</button> <button id="destroy">Destroy the dialog!</button> <script type="text/javascript" src="jqueryui1.6rc2/jquery-1.2.6.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.core.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.dialog.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.resizable.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.draggable.js"></script> <script type="text/javascript"> //define function to be executed on document ready $(function(){ //define doOk function var doOk = function() { //close the dialog $("#myDialog").dialog("close"); } //define config object var dialogOpts = { modal: true, overlay: { background:"url(img/modal.png) repeat" }, buttons: { "Ok!": doOk }, height: "400px", autoOpen: false }; //create the dialog $("#myDialog").dialog(dialogOpts); //define click handler for the button $("#openDialog").click(function() { //open the dialog $("#myDialog").dialog("open"); }); //define click handler for destroy $("#destroy").click(function() { //destroy dialog $("#myDialog").dialog("destroy"); }); }); </script> </body></html> Save the changes as dialog8.html and try out the new file. You'll find that you can open and close the dialog as many times as you want until the Destroy the dialog! button is clicked. After this, the dialog will no longer appear (although it will still exist in the DOM). To fully remove the dialog mark-up from the page, we can simply chain the remove jQuery method onto the end of the destroy method call.

The communication system's Dial Plan is a collection of Dial Rules. The purpose of the Dial Plan is to control the routing of calls based on dialed numbers. Different Dial Rules within the Dial Plan are selected by matching dialed number patterns (the user part of a SIP URL). The following types of dial rules can be created in sipXecs: Voicemail: This is used to configure the system Voicemail server. Custom: This is used to build custom call routing to gateways. Long Distance: This is used to route long-distance dialed calls. Local: This is used to route local phone calls to gateways. Emergency: This is used for emergency call routing to gateways. International: This is used for routing calls to international destinations to gateways. Attendant: This is used for routing calls to auto attendants defined in the system. Dial Plan configuration is located under the System menu. Clicking on the Dial Plan menu item will display the following page: As seen in the above screenshot, there are some default dial rules already created, that allow the administration to simply add gateways and enable them. Existing Dial Rules can be edited by clicking on the rule's name. Additionally new rules can be created with the Add New Rule  drop-down menu. Dial rules are processed in the order that they are listed so more specific dial plan entries should be listed near the top. Additionally, if a dial rule is matched and the user does not have permission to use the dial plan entry the call will fail. Voicemail dial rule There is typically only one voicemail per phone system. Its purpose is to control how voicemail is routed for mailboxes and how the voicemail system is accessed. The following screenshot shows the default Voicemail system settings:     The following options are available in Voicemail Dial Rules: Enabled: Dial rules can be enabled or disabled in the system as the administrator wishes. A rule might be disabled if it is being tested or if a temporary rule gets created to address a particular problem. Name: This is a descriptive name for the dial rule. Description: This is a description of what the dial rule is for, to help in documentation. Internal station extension length: The number of digits used for internal extensions in your installation. Add another voicemail rule if you have phones with different length extensions. Voicemail extension: The number dialed to reach the voicemail server. This can be left empty to disable Voicemail. Voicemail inbox prefix: The number dialed when directly dialing or forwarding a call to a user's voicemail box. Voicemail type: The Voicemail type can be set to Internal Voicemail Server or Exchange Voicemail Server. Microsoft Exchange 2007 can be used as an alternative to the internal Voicemail Server. Select Exchange Voicemail Server and enter its name or IP address into the field provided. For every user or group of users, the desired voicemail server needs to be selected. Select the Permissions tab in the Users menu to do this. Choose only either the internal voicemail server or Exchange 2007 as these do not work when both confi gured on the system. Note: Due to a Microsoft problem Message Waiting Indication (MWI) does not work with Exchange 2007. Other external voicemail servers can be used instead of Exchange 2007 using this configuration. Voicemail host: IP address or name of the voicemail server. Leave empty if the voicemail server runs on the same computer as the call server. Schedule: All dial plan entries can be allowed to operate based on a schedule. Voicemail is typically not scheduled. Custom dial rules Custom dial rules are very useful for controlling special call scenarios. For example, if you are connecting a gateway to another PBX that has extensions 400: 599, a custom dial rule could be configured to send calls to that gateway when a three digit number is passed that begins with a 4 or a 5. The following screenshot show the custom Dial Rule page: The following options are available for custom Dial Rules: Enabled: Dial rules can be enabled or disabled in the system as the administrator wishes. A rule might be disabled if it is being tested or if a temporary rule gets created to address a particular problem. Name: A descriptive name for the dial rule. Description: More information about this dial rule and what it is used for. Dialed Number: Defines the digits that this rule will match. Any number of prefixes and trailing digits can be added with the Add hyperlink. Prefixes: Prefixes are the initial part of a dialed number (or SIP URL). A prefix can be integers (for example,2), ranges (for example, 1-5), or lists (for example, 2, 3, 4). Any number of digits (Suffix): Defines how many digits will follow the prefix. Values from 0 to 18 or Any Number of Digits can be selected. Required Permissions: Defines the user permissions required to access the dial rule. 900 Dialing, Attendant Directory, International Dialing, Local Dialing, Long Distance Dialing, Mobile Dialing, Record System Prompts, Toll Free, or Voice Mail. Resulting Call: Defines what digits besides the dialed digits will be sent to the gateway. Dial(new prefix): Allows the administrator to change the prefix that will be passed to the gateway. This entry may be left blank to drop the prefix that was detected (when Matched suffix is selected in the following drop-down menu). And append (Suffix): The and append drop-down menu item can have one of three values; Nothing, Matched suffix, or Entire dialed number. Schedule: A schedule can be defined that determines when the custom dial rule can be used. Gateways: A list of gateways available to this dial rule. See the Adding gateway section earlier in this article for information about gateway selection and user locations. Long distance dial rules Long distance dial rules are used by the system to control whether the users are permitted to dial long-distance numbers or to select different gateways for least-cost routing of calls. The default long distance Dial Rule is disabled by default in the system. The rule is triggered by a number consisting of a PSTN prefix followed by the Long Distance prefix and a variable part starting with one of the patterns specified in the Area Codes field. The following settings are available for long distance dial rules (click on Show Advanced Settings to see all of the dial rule's options): Enabled: Dial rules can be enabled or disabled in the system as the administrator wishes. A rule might be disabled if it is being tested or if a temporary rule gets created to address a particular problem. Name: A descriptive name for the dial rule. Description: More information about this dial rule and what it is used for. Permission : Defines the user permissions a user must have to use this dial rule. Treat PSTN prefix as optional : If this is checked the caller does not have to dial the PSTN prefix (following). Dialing the PSTN prefix is optional by default. This item is only shown if Show Advanced Options is selected. PSTN prefix : The prefix dialed by the caller and dropped before the call is sent to the gateway. The Long Distance prefix is always sent to the gateway. Treat long distance prefix as optional: If this is checked the caller does not have to dial the long distance prefix. This item is only shown if Show Advanced Options is selected. Long distance prefix: The prefix dialed by the caller and sent to the gateway. Area codes  : Optional comma-separated list of prefixes that specify the dialed numbers to which this rule applies. If the Area Codes field is empty the rule will match any number starting with the PSTN prefix followed by the Long distance prefix. External number length: The number of digits in the resulting number sent to the gateway. The PSTN prefix and the long distance prefix are not counted. Valid values are—Any number of digits and 5-15 digits. Schedule: A schedule can be defined that determines when the custom dial rule can be used. Gateways: A list of gateways available to this dial rule. See the Adding gateway section earlier in this article for information about gateway selection and user locations. The resulting call is sent to the gateways specified in the gateway list in the order gateways are listed.

(For more resources on Plone, see here.) Introducing versioning Now that you have learned how to add various types of content, from pages to events to news items, we're ready to introduce a feature of Plone called versioning, which is an important part of content management. The content items you work with in your Plone site may go through many changes over time. Plone provides versioning information to help you manage your content from the time it was initially created through to the current version. By default, Plone provides versioning for the following content types: Pages News Items Events Links Other content types can be configured to provide versioning through the Plone Control Panel under Types. Although you may enable the File type to use versioning, the only changes that are tracked are those items actually describing the File (for example, Title, Description, and so on). The changes to the contents of the File are not tracked. Creating a new version Versions are created each time you save your content. Note that there is a Change note field at the bottom of the Edit page for content items with versioning enabled: The information entered in the Change note field will be stored along with other versioning information, which you are able to view through the History tab. Viewing the version history You can view the list of all of the versions of a content item by clicking on the History tab for that content item. In the History view that you can see in the following screenshot, the most recent version is listed fi rst. Clicking on any of the column headers will re-sort the listing based on that column heading. The most current version is always labeled Working Copy in the History view. Previewing previous versions To preview a specific version, simply click the preview link of the desired revision. In the following example, revision 3 has been identified, and will be displayed if this link is clicked: On the subsequent page, you may either click on the jump down link to the point of the content preview: or you may scroll down the page in order to see the actual preview:

Before we start exploring the slider, let me try to give you a complete picture of its functionality with a simple example. Google Finance uses a horizontal slider, showing the price at a given day, month, and year. Although this particular module is built in Flash, we can build a similar module using the script.aculo.us slider too. To understand the concept and how it works, look at the following screenshot: Now that we have a clear understanding of what the slider is and how it appears in UI, let's get started! First steps with slider As just explained, a slider can handle a single value or a set of values. It's important to understand at this point of time that unlike other features of script.aculo.us, a slider is used in very niche applications for a specific functionality. The slider is not just mere functionality, but is the behavior of the users and the application. A typical constructor syntax definition for the slider is shown as follows: new Control.Slider(handle, track [ , options ] ); Track mostly represents the <div> element. Handle represents the element inside the track and, as usual, a large number of options for us to fully customize our slider. For now, we will focus on understanding the concepts and fundamentals of the slider. We will surely have fun playing with code in our Code usage for the slider section. Parameters for the slider definition In this section we will look at the parameters required to define the slider constructor: track in a slider represents a range handle in a slider represents the sliding along the track, that is, within a particular range and holding the current value options in a slider are provided to fully customize our slider's look and feel as well as functionality It's time to put the theory into action. We need the appropriate markup for working with the slider. We have <div> for the track and one <div> for each handle. The resulting code should look like the snippet shown as follows: <div id="track"><div id="handle1"></div></div> It is possible to have multiple handles inside a single track. The following code snippet is a simple example: <div id="track"><div id="handle1"></div><div id="handle2"></div></div> Options with the slider Like all the wonderful features of script.aculo.us, the slider too comes with a large number of options that allow us to create multiple behaviours for the slider. They are: Axis: This defines the orientation of the slider. The direction of movement could be horizontal or vertical. By default it is horizontal. Increment: This defines the relation between value and pixels. Maximum: This is the maximum value set for the slider to move to. While using a vertical slider from top-to-bottom, the bottom most value will be the maximum. And for a horizontal slider from left-to-right, the right most value will be the maximum value. Minimum: This is the minimum value set for the slider to move to. While using a vertical slider from top-to-bottom, the top most value will be the minimum. And for a horizontal slider from left-to-right, the left most value will be the minimum value approach for horizontal slider. Range: This is the fixed bandwidth allowed for the values. Define the minimum and maximum values. Values: Instead of a range, pass a set of values as an array. SliderValue: This sets the initial value of the slider. If not set, will take the extreme value of the slide as the default value. Disabled: As the name suggests, this disables the slider functionality. Some of the functions offered by the slider are: setValue:This will set the value of the slider directly and move it to the value position. setDisabled: This defines that the slider is disabled at runtime. setEnabled: This can enable the slider at runtime. Some of the callbacks supported by the slider are: onSlide: This is initiated on every slide movement. The called function would get the current slider value as parameter onChange: Whenever the value of the slider is changed, the called function is invoked. The value can change due to the slider movement or by passing the setValue function. Types of slider script.aculo.us provides us the flexibility and comfort of two different orientations for the slider: Vertical slider Horizontal slider Vertical slider When the axis orientation of a slider is defined as vertical, the slider becomes and acts as a vertical slider. Horizontal slider When the axis orientation of a slider is defined as horizontal, the slider becomes and acts as a horizontal slider. So let's get our hands dirty with code and start defining the constructors for horizontal and vertical slider with options. Trust me this will be fun.

Overview Around a decade ago, it was possible for a single, precocious developer to build an entire SOA-like platform single-handedly. Granted, it was not an easy task to construct a service container and surround it with robust connection management, application security, transaction management, and reliable messaging, but it was at least an attainable goal. It was a proud achievement to build a toy application server or MOM platform in one’s basement. Those were simpler times. Today’s SOA suite is far too vast for one person to build, and uses computer science that is more advanced than a basement hacker can contend with. In the first place, today’s services—as I argue in my new book SOA Cookbook (Packt, 2008)—are designed as processes rather than simple method calls. Building an SOA process engine means brushing up on, or learning from scratch, Finite State Automata, Petri Nets, and, perhaps, the Pi Calculus. Additionally, these processes use business rules to decide on next actions. Building the required rules engine presupposes proficiency in forward-chaining rule definitions, the RETE algorithm, and, possibly, genetic algorithms. Toy SOA is a relic of the past; today’s SOA requires a large team of very smart people. Still, for all its might, today’s SOA is merely reactive. An SOA process provides a business function that reacts to requests. If the function is requested ten thousand times, the process is run ten thousand times. It is not in SOA’s mandate to make sense of trends, or to find suspicious happenings, across those ten thousand invocations. SOA’s job is to be a workhorse, serving the requests. It is not an anomaly watchdog or a slice-and-dice business analysis tool. Still, many enterprises seek just such a capability. Not surprisingly, SOA vendors are starting to add Complex Event Processing (CEP) to their solution. CEP listens on the bus for the same events that pass in and out of SOA processes, but—unlike SOA—is concerned mainly with the detection of patterns that emerge across events. It does this, as we’ll discuss, by applying event-pattern matching rules to the events. CEP thus relies on both SOA’s event bus and its rules engine. Not only does CEP fit in the SOA architecture, but also provides the watchdog capability that business stakeholders find so valuable. CEP and SOA CEP isn’t a new technology but is only now gaining traction in the marketplace. David Luckham wrote the definitive book on CEP (The Power of Events, Addison Wesley), which was published in 2002. Over the years several academic implementations have been developed, notably Stanford’s Rapide and Cornell’s Cayuga. Numerous CEP startups failed in the early days of CEP, during the rise and fall of dotcom in the late 1990s. It was to help market one of these companies, ePatterns, that Luckham started work on his book. The company didn’t pan out, as Luckham reminisces in his article “A Short History of Complex Event Processing Part 3: The Formative Years.” (http://complexevents.com/?p=553), but the book lived on, becoming the bible of events. Until recent years, the most established commercial implementations came from small vendors, such as Coral8 and Streambase. But within the past few years the major SOA vendors—who had previously kept arms-length from CEP, doubtful of its market potential— have started to incorporate CEP into their stacks. IBM, for instance, recently acquired Coral8. TIBCO aggressively sells its CEP tool, BusinessEvents, in its SOA and BPM deals. Oracle, thanks to its BEA acquisition, offers a product called “Oracle” CEP. The combined SOA/CEP offering is encouraging, because CEP’s value comes not from its intrinsic value but from its contribution to an overall solution. SOA vendors, in a sense, have been in the “overall solution” business for years. They promote the idea that business architecture should be built on services, and they provide a platform on which to build those services. But what’s always been missing was a tool to watch the services, to make sense of what’s happening operationally. What CEP and SOA have in common is events. Both technologies use events, but for different purposes. SOA processes use events to drive control flow. An SOA process is started by an event, and during the course of its execution waits for further events to propel it forward. Events in SOA, in effect, force process transitions. Most SOA processes not only receive events but also send events. When a process sends an event, another process receives it. Elaborate choreographies arise when the processes of multiple organizations engage in conversations of events. CEP, by contrast, is a rules engine that uses events to trigger rule evaluations. CEP is constantly listening on the SOA bus for events. As we explore in more detail below, by using event pattern matching rules, CEP is able to infer causal connections between seemingly disparate events. CEP can also aggregate a set of inconsequential low-level events into a single, business-meaningful complex event. In stock trading, for example, a customer’s purchase of shares is the combination of four events (keeping it simple): The customer’s request to the broker to buy the shares The broker’s placement of the order The result of the order, including the price at which the shares were bought The broker’s response back to the customer. When CEP detects these four events, it publishes a complex event—BuyOrderCompleted, let’s call it—back to the bus, where interested listeners may pick it up. The following figure illustrates the sequence of steps; this design is discussed in more detail below. CEP can also detect breakdowns in the buy order. For example, if the broker fails to respond back to the customer in a timely fashion, CEP can easily spot this and publish a BuyOrderBrokerResponseLate event. CEP can also spot anomalies that span multiple orders. For example, it can detect suspicious broker activities like a buy-ahead, in which the broker, when directed by a customer to buy shares, buys his own lot of shares first, and sells them after placing the customer’s order. (The broker makes a nice profit from this furtive trade; the customer’s order, when large enough, drives the price up, so when the broker sells, he comes out ahead.) It would be fiendishly difficult to build a detection mechanism for buy-aheads into SOA processes; CEP, as a watchdog off to the side, is much better equipped. This trade monitoring example is one of many CEP use cases. CEP use cases arise naturally from SOA use cases. If events move through the bus to drive services and processes, there is bound to be some important business reason to infer complex events from them. Indeed, many CEP use cases require SOA. Fraud detection, for example, which checks for anomalies in transactions on an account, must reside on an SOA platform with processes in place to perform transactions on accounts. The fraud detection rules must understand the structure of the account events and the protocol governing how they are exchanged. CEP in the SOA Stack The following figure shows where CEP fits in the stack offered by major SOA vendors. The three layers of the operational stack, shown on the right side of the diagram, are the Enterprise Service Bus (ESB), the Orchestration/Service Engine, and the BPM engine. The Orchestration Engine runs SOA processes, and it uses the ESB, which acts as a full-featured message broker, to send and receive events to its partner systems. Processes that involve both system and human work are split between the Orchestration Engine and the BPM Engine. A workflow process running on the BPM Engine invokes SOA processes in the Orchestration Engine to perform system actions; an SOA process running on the Orchestration Engine uses processes in the BPM Engine to delegate human work. You can refer SOA Cookbook (Packt, 2008) for an expanded discussion of the stack. CEP and its cousin Business Activity Monitoring (BAM) are shown as pieces off to the side. They are the not part of the core operational SOA platform, but rather provide an important business monitoring capability. BAM, in most implementations, is a summary view of business processes in the system. Like CEP, it observes the progress of operational processes, though it handles this data somewhat differently. BAM’s purpose is to create a rolled-up, read-only data view. CEP, in contrast, tries to infer complex events that can trigger follow-on actions. Both CEP and BAM funnel (as the figure shows) have large volume of events from the operational stack, reducing all that chatter to a smaller set. The following table maps this stack to vendors. We consider the four major SOA vendors: IBM, Oracle, BEA, and TIBCO. BAM is omitted from the table; CEP is our focus. Vendor BPM Orchestration ESB CEP TIBCO iProcess BusinessWorks ActiveMatrix Service Grid/Bus BusinessEvents BEA AquaLogic BPM Weblogic Integration AquaLogic Service Bus Oracle CEP Oracle "Fusion" BPA Suite "Fusion" BPEL Process Manager "Fusion" Enterprise Service Bus Oracle CEP (acquired from BEA) IBM Websphere Process Server, FileNet Websphere Process Server, Websphere Interchange Server Websphere Enterprise Service Bus, Websphere Message Broker Coral8 (recent acquisition) The operational stack supports a distributed architecture in which the activities of client applications and partner services, both internal and external to the organization, are coordinated by orchestration processes. Clients and partners communicate with these processes through the ESB. Internal connections typically use MOM queues to access the bus; external connections use SOAP over HTTP. The orchestration processes, besides coordinating partner activities, also interface with backend systems (databases, mainframes, and so on) and use BPM to delegate manual work to human actors. The following figure illustrates this architecture. CEP consists of a set of rules that listen for events from the bus. (A publish-subscribe messaging infrastructure allows CEP to get these events without disrupting the operational processes.) CEP rules, as we discussed above, infer complex events from these operational events. They send complex events back on the bus on orchestration queues, where, as we discuss further below, they are picked up and handled by CEP-aware orchestration processes. CEP must be sufficiently scalable to handle the high volume of events on the bus. There is more to this than sheer processing speed. CEP, like most rule-based systems, is stateful. It keeps its state (i.e., its current set of asserted facts) in a datastore called Working Memory. For performance reasons, Working Memory should be kept in physical memory, and paged out to disk when necessary. Using an RDBMS instead of memory would prove to be simply too slow and only a few commercial databases can handle updates at the volumes of events on a bus anyway. This memory should be fault-tolerant, given the business criticality of CEP. Such an implementation is full of the sort of thorny performance design issues in which SOA vendors have the greatest expertise. BAM works somewhat differently from CEP. Orchestration and BPM processes have state, and BAM uses this state, combined with business data from backend systems, to present a consolidated view of the state of the processes. For example, rather than tracking just order processes, BAM might also track the orders themselves, as they appear in the backend order system. In the previous figure, we labeled this piece as BAM/BI (for business intelligence), because most BAM implementations by themselves lack the ability to incorporate application data. Combining process state with application data often requires the combination of BAM and some sort of BI or analytics tool. Whereas BAM merely presents a view of the system, CEP, by creating events that it has inferred from its observations, serves as an active participant. SOA platforms with CEP are self-healing; CEP watches what’s happening operationally and sounds up when it detects a significant occurrence. The dotted line in the previous figure from CEP to BAM suggests that complex events created by CEP could be incorporated into the BAM dashboard. Thus, the BAM dashboard for the trading application could show statistics on completed orders or buy-aheads per broker. The mechanism by which CEP notifies BAM of complex events is implementation-specific.

As more and more users start to explore and use Oracle VM Manager, more troubleshooting and tweaks will come up. This is by no way an exhaustive list and is also not intended to be. Please do participate as much as possible in forums and contribute your tips and tricks with the community. Oracle VM Manager login takes too much time I have faced this issue very often and normally if you are unlucky you ought to get this type of error while installing. For instance this error message says nothing about the memory issue: Failed at "Could not get DeploymentManager".This is typically the result of an invalid deployer URI format beingsupplied, the target server not being in a started state or incorrectauthentication details being supplied.More information is available by enabling logging -- please see theOracle Containers for J2EE Configuration and Administration Guide fordetails.FailedPlease see /var/log/ovm-manager/ovm-manager.log for more information.Deploying application failed.Please check your environment, and re-run the script:/bin/sh scripts/deployApp.shAborting installation. Please check the environment and rerunrunInstaller.sh. But when you upgrade your VM Manager OS with more memory you'll be able to continue with the installation. Sometimes, you may also get all kinds of errors, such as the following one: Internal Exception: java.lang.OutOfMemoryError: Java heap space And they clearly point to the memory issue. This suggests that your OC4J may need more memory. Let's run the following commands to check the log information: cat  /var/log/ovm-manager/oc4j.log | grep "heap" If your OC4J ran out of memory you would typically get that heapsize error. To fix this go back to the console and examine the values of the following OC4J_JVM_ARGS function in the /opt/oc4j/bin/oc4j configuration file: Edit the following OC4J_JVM_ARGS="-XX:PermSize=256m -XX:MaxPermSize=512m function and give more memory to the OC4J. Save the information and quit: Restart the service OC4J: service oc4j stopservice oc4j start HVM guest creation fails Normally there are many actions and functionalities within Oracle VM Manager that require the host to be truly HVM-aware, which means that 64-bit (preferably) Oracle VM Servers must be running with hardware virtualization support on the chipset level. Having said that, both Intel and AMD support it and it is highly unlikely that you will come across new machines that do not support that. However, always check the compatibility within a specific family and check whether the support is turned on or off. Nonetheless, you could be using some reusable older hardware that may or may not support HW-assist virtualization. If you are confronted with the following message: "Error: There is no server supporting hardware virtualization in the selected server pool. " Then you'll have a reason to worry and check your hardware, and carry out the following commands on the VM Server that does not allow you to create a HVM: Cat /proc/cpuinfo | grep –E 'vmx|smx' Use the preceding command if your hardware is HVM-aware, then you should get some reply as shown in the following screenshot: If you don't get a response, then you might have a problem. For instance we pick up another VM Server which we for sure know does not have a HVM support or HW-assist virtualization: Also ensure that the virtualization support is enabled at the HW level in the BIOS. Then run the following commands to see if the Operating System supports HVM: As you have seen in the preceding screenshot, we then quickly logged into the VM Server which we knew does not support HVM and did not get a reply from the 172.22.202.111 VM Server. Whereas, the x64 bit version with built-in, BIOS-enabled HVM support returns the values in the form of xen_caps. xen_caps : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64 So if your CPU does not support HVM, use the PVM (Paravirtualized Method) to create your VM.

Code usage for sliders with options We are now done with the most important part of the slider: the implementation of the slider in our applications. But wait, we need the slider to suit our applications, right? So let's customize our slider with options. We have mentioned earlier that track is the range of values. So let's first define the range for our slider. window.onload = function() { new Control.Slider('handle1' , 'track1', { axis:'vertical', range:$R(1,100)} The range option uses the Prototypes' objectRange instance. Hence, we declare it using $R (minimum, Maximum). Everything looks neat until here. Let's add some more options to our constructor, onSlide(). Using the onSlide() callback every time, we drag the slider and the callback is invoked. The default parameter passed to onSlide() is the current slider value. window.onload = function() { new Control.Slider('handle1' , 'track1', { axis:'vertical', range:$R(1,100), onSlide: function(v) { $('value1').innerHTML = "New Slide Value="+v;} }} We have added a div called value1 in our HTML code. On dragging the slider, we will update the value1 with the current slider value. OK, so let's see what happened to our slider to this point. Check out the following screenshot: Impressed? And, we are not done yet. Let's add more options to the slider now. You may ask me, what if the slider in the application needs to be at a particular value by default? And I will say use the sliderValue option. Let's make our slider value 10 by default. Here is the snippet for the same: window.onload = function() {      new Control.Slider('handle1' , 'track1',     {   axis:'vertical',   range:$R(1,100),   sliderValue: 10,   onSlide: function(v) { $('value1').innerHTML = "New Slide                                                 Value="+v;}} And, you should see the slider value at 10 when you run the code. Now your dear friend will ask, what if we don't want to give the range, but we need to pass the fixed set of values? And you proudly say, use the values option. Check out the usage of the values options in the constructor. window.onload = function() { new Control.Slider('handle1' , 'track1', { range:$R(1,25), values:[1, 5,10,15,20,25], onSlide:function(v){ $('value1').innerHTML = "New Slide Value="+v;} } );} We have added a set of values in the array form and passed it to our constructor. Let's see what it looks like. Tips and tricks with the slider After covering all the aspects of the slider feature, here is a list of simple tips and tricks which we can make use of in our applications with ease. Reading the current value of the slider script.aculo.us "genie" provides us with two callbacks for the slider to read the current value of the slider. They are: onSlide onChange Both these callbacks are used as a part of options in the slider. onSlide contains the current sliding value while the drag is on. The callback syntax is shown as follows: onSlide: function(value) {// do something with the value while sliding. Write or Edit thevalue //of current slider value while sliding} onChange callback will contain the value of the slider while the sliding or the drag event ends. After the drag is completed and if the value of the slider has changed then the onChange function will be called. For example, if the slider's current value is set to 10 and after sliding we change it to 15, then the onChange callback will be fired. The callback syntax is shown as follows: onChange: function(value){// do anything with the "changed" and current value} Multiple handles in the slider Now, a thought comes to our mind at this point: Is it possible for us to have two handles in one track? And, the mighty script.aculo.us library says yes! Check out the following code snippet and screenshot for a quick glance of having two handles in one track: HTML code<div id="track1"><div id="handle1"></div><div id="handle2"></div></div> JavaScript code for the same: window.onload = function() { new Control.Slider(['handle1','handle2'] , 'track1');} Now, check out the resulting screenshot having two handles and one track: The same can also be applied for the vertical slider too.

The following screenshot shows a dialog widget and the different elements that it is made of: A basic dialog A dialog has a lot of default behavior built-in, but few methods are needed to control it programmatically, making this a very easy widget to use that is also highly configurable. Generating it on the page is very simple and requires a minimal underlying mark-up structure. The following page contains the minimum mark-up that's required to implement the dialog widget: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html lang="en"> <head> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.dialog.css"> <link rel="stylesheet" type="text/css" href="jqueryui1.6rc2/themes/flora/flora.resizable.css"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>jQuery UI Dialog Example 1</title> </head> <body> <div id="myDialog" class="flora" title="This is the title">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean sollicitudin. Sed interdum pulvinar justo. Nam iaculis volutpat ligula. Integer vitae felis quis diam laoreet ullamcorper. Etiam tincidunt est vitae est. Ut posuere, mauris at sodales rutrum, turpis tellus fermentum metus, ut bibendum velit enim eu lectus. Suspendisse potenti. Donec at dolor ac metus pharetra aliquam. Suspendisse purus. Fusce tempor ultrices libero. Sed quis nunc. Pellentesque tincidunt viverra felis. Integer elit mauris, egestas ultricies, gravida vitae, feugiat a, tellus.</div> <script type="text/javascript" src="jqueryui1.6rc2/jquery-1.2.6.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.core.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.dialog.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.resizable.js"></script> <script type="text/javascript" src="jqueryui1.6rc2/ui/ui.draggable.js"></script> <script type="text/javascript"> //define function to be executed on document ready $(function(){ //create the dialog $("#myDialog").dialog(); }); </script> </body></html> Dialog properties An options object can be used in a dialog's constructor method to configure various dialog properties. Let's look at the available properties: Save this as dialog1.html in the jqueryui folder. A few more source files are required, specifically the ui.resizable.js and ui.draggable.js files and the flora.resizable.css stylesheet. The JavaScript files are low-level interaction helpers and are only required if the dialog is going to be resizable and draggable. The widget will still function without them. The dialog flora theme file is a mandatory requirement for this component, although the resizable one isn't. Other than that, the widget is initialized in the same way as other widgets. When you run this page in your browser, you should see the default dialog widget shown in the previous screenshot, complete with draggable and resizable behaviors. One more feature that I think deserves mentioning here is modality. The dialog comes with modality built-in, although it is disabled by default. When modality is enabled, a modal overlay element, which covers the underlying page, will be applied. The dialog will sit above the overlay while the rest of the page will be below it. The benefit of this feature is that it ensures the dialog is closed before the underlying page becomes interactive again, and gives a clear visual indicator that the dialog must be closed before the visitor can proceed. Custom dialog skins The dialog's appearance is easy to change from the flora theme used in the first example. Like some of the other widgets, certain aspects of the default or flora themes are required to make the widget function correctly. Therefore, when overriding styles, we need to be careful to just override the rules related to the dialog's display. When creating a new skin for the default implementation, including resizable behavior, we have a lot of new files that will need to be created. Apart from new images for the different components of the dialog, we also have to create new images for the resizing handles. The following files need to be replaced when skinning a dialog: dialog-e.gif dialog-n.gif dialog-ne.gif dialog-nw.gif dialog-s.gif dialog-se.gif dialog-sw.gif dialog-title.gif dialog-titlebar-close.png dialog-titlebar-close.png To make it easier to remember which image corresponds to which part of the dialog, these images are named after the compass points at which they appear. The following image illustrates this: Note that these are file names as opposed to class names. The class names given to each of the different elements that make up the dialog, including resizable elements, are similar, but are prefixed with ui- as we'll see in the next example code. Let's replace these images with some of our own. In a new file in your text editor, create the following stylesheet: .flora .ui-dialog, .flora.ui-dialog { background-color:#99ccff;}.flora .ui-dialog .ui-dialog-titlebar, .flora.ui-dialog.ui-dialog-titlebar { background:url(../img/dialog/my-title.gif) repeat-x; background-color:#003399;}.flora .ui-dialog .ui-dialog-titlebar-close, .flora.ui-dialog.ui-dialog-titlebar-close { background:url(../img/dialog/my-title-close.gif) no-repeat; }.flora .ui-dialog .ui-dialog-titlebar-close-hover, .flora.ui-dialog.ui-dialog-titlebar-close-hover { background:url(../img/dialog/my-title-close-hover.gif) norepeat;}.flora .ui-dialog .ui-resizable-n, .flora.ui-dialog .ui-resizable-n { background:url(../img/dialog/my-n.gif) repeat center top;}.flora .ui-dialog .ui-resizable-s, .flora.ui-dialog .ui-resizable-s { background:url(../img/dialog/my-s.gif) repeat center top;}.flora .ui-dialog .ui-resizable-e, .flora.ui-dialog .ui-resizable-e { background:url(../img/dialog/my-e.gif) repeat right center; }.flora .ui-dialog .ui-resizable-w, .flora.ui-dialog .ui-resizable-w { background:url(../img/dialog/my-w.gif) repeat left center;}.flora .ui-dialog .ui-resizable-ne, .flora.ui-dialog .ui-resizable-ne{ background:url(../img/dialog/my-ne.gif) repeat;}.flora .ui-dialog .ui-resizable-se, .flora.ui-dialog .ui-resizable-se{ background:url(../img/dialog/my-se.gif) repeat;}.flora .ui-dialog .ui-resizable-sw, .flora.ui-dialog .ui-resizable-sw{ background:url(../img/dialog/my-sw.gif) repeat;}.flora .ui-dialog .ui-resizable-nw, .flora.ui-dialog .ui-resizable-nw{ background:url(../img/dialog/my-nw.gif) repeat;} Save this as dialogTheme.css in the styles folder. We should also create a new folder within our img folder called dialog. This folder will be used to store all of our dialog-specific images. All we need to do is specify new images to replace the existing ones used by flora. All other rules can stay the same. In dialog1.html, link to the new file with the following code, which should appear directly after the link to the resizable stylesheet: <link rel="stylesheet" type="text/css" href="styles/dialogTheme.css"> Save the change as dialog2.html. These changes will result in a dialog that should appear similar to the following screenshot: So you can see that skinning the dialog to make it fit in with your existing content is very easy. The existing image files used by the default theme give you something to start with, and it's really just a case of playing around with colors in an image editor until you get the desired effect. Dialog properties An options object can be used in a dialog's constructor method to configure various dialog properties. Let's look at the available properties: Property Default Value Usage autoOpen true Shows the dialog as soon as the dialog method is called bgiframe true Creates an <iframe> shim to prevent <select> elements showing through the dialog in IE6 - at present, the bgiframe plugin is required, although this may not be the case in future versions of this widget buttons   {} Supplies an object containing buttons to be used with the dialog dialogClass ui-dialog Sets additional class names on the dialog for theming purposes draggable true Makes the dialog draggable (use ui.draggable.js) height 200(px) Sets the starting height of the dialog hide none Sets an effect to be used when the dialog is closed maxHeight none Sets a maximum height for the dialog maxWidth none Sets a maximum width for the dialog minHeight 100(px) Sets a minimum height for the dialog minWidth 150(px) Sets a minimum width for the dialog modal false Enables modality while the dialog is open overlay {} Object with CSS properties for the modal overlay position center Sets the starting position of the dialog in the viewport resizable true Makes the dialog resizable (also requires ui.resizable.js) show none Sets an effect to be used when the dialog is opened stack true Causes the focused dialog to move to the front when several dialogs are open title none Alternative to specifying title on source element width 300(px) Sets the original width of the dialog

Creating A File System Let us start building a new template for Zen Cart by creating a new folder under includes/templates/. Let us name it Packt (or whatever you like). But remember to use underscore instead of spaces in a long name. Avoid using Book Shop. Instead, use book_shop or BookShop. images' folder —will contain all the images needed for the template. css' folder — will contain all the CSS files for the template. It's better to copy all the files from the includes/templates/template_default/css directory to this css folder. common' folder — will contain the common files for the template. You may copy the files from the includes/templates/template_default/common folder, and edit those to suit your needs. sideboxes'folder — will contain module-specific sideboxes. Here, you can add new sideboxes, which you are going to use. templates folder — contains page-specific templates. Whenever you want to change a page's layout, copy the template for that page to this directory and modify it as required. Information regarding a template is located in the template_info.php file. You need to create a new template_info.php file for the new template. Copy the file called includes/templates/template_default/template_info.php into the new template folder, and then open the template_info.php file in your favorite text editor. Change the text between each set of single quotes to suit your new template. <?php $template_name = 'Packt Publishing'; $template_version = 'Version 1.0'; $template_author = 'Suhreed Sarkar'; $template_description = 'This template is designed for Packt Publishing'; $template_screenshot = ''; ?> Remember to keep the single quotes. Your template name does not need to be identical to your folder name, and you can use spaces to make it read well, but it is best to keep them similar. Leave the space between the quotes for the template screenshot field empty for now, as you don't have one yet. When you've finished, your new file structure should appear as follows: Open your Admin panel and navigate to Tools | Template Selection. Click the Edit button, then choose Packt Publishing from the drop-down menu and click the Update button. Now, navigate to Tools | Layout boxes controller, and click the Reset button at the bottom of the page. Your new template is now enabled and ready to be customized. Using Overrides When building a new template for Zen Cart, you can use its powerful overriding feature. Overriding means using some template as the base and extending it by adding different properties through separate templates. For example, you may want to make some modifications to the default template—template_default. You could modify the files in the template_default directory to do this. But due to its overriding character, you can add the changes in the new template, say packt, which will apply the changes to the shop. In fact, you can override any file in the path includes/templates/ template_default. Files in this directory generally determine the layout and the HTML formatting of your web pages. By default, Zen Cart has two standard templates: template_default and classic, both of which are located in the includes/templates/ folder. Out of these two standard templates, only template_default contains a full set of files. Every other template contains only the files that differ from template_default. If your template does not contain a particular file, Zen Cart will pull that file from template_default. Graphics You need to add your templates graphics to the appropriate folders. The header image, logo, background image, background image for sidebox headings, and so on should be placed in the images directory under your template directory. If you want to change the buttons and icons, create the graphic files in the GIF, JPG or PNG format and put them in the /includes/templates/template_name/buttons/language_name folder. Then, update the button_names.php file to define the button image file name, and the ALT texts for those images. Sideboxes You do not need to copy existing sideboxes from the template_default directory, as these will automatically be displayed. If you are planning to develop a new sidebox, put the template for that sidebox in the sideboxes folder under your template directory. A sidebox consists of three files, which are located in the includes directory: modules/sideboxes/template_name/name_of_sidebox.php' languages/english/extra_definitions/template_name/ name_of_sidebox_defines.php ' templates/template_name/sideboxes/tpl_name_of_sidebox.php ' You need to replace template_name and name_of_sidebox with you template name and the sidebox name respectively. For example, let us build a sidebox named my_sidebox. Then, my_sidebox.php file will read like this: <?php $show_my_sidebox = true; if ($show_my_sidebox == true){ require($template->get_template_dir('tpl_my_sidebox.php', DIR_WS_TEMPLATE, $current_page_base,'sideboxes'). '/tpl_my_sidebox.php'); $title = BOX_HEADING_MY_SIDEBOX; $left_corner = false; $right_corner = false; $right_arrow = false; require($template->get_template_dir($column_box_default, DIR_WS_TEMPLATE, $current_page_base,'common') . '/' . $column_box_default); } ?> This page actually defines what is to be shown in that sidebox. Note that this page also includes the corresponding template file. Here, we have used a constant BOX_HEADING_MY_SIDEBOX. You need to define this in the includes/languages/english/extra_definitions/packt/my_sidebox_defines.php file. This file will look like this: <?php define('BOX_HEADING_MY_SIDEBOX', 'My Sidebox'); ?> Now, you have to build its template file includes/templates/packt/sideboxes/tpl_my_sidebox.php, which will read as: <?php $content = "This is my first Sidebox. I have created it in 5 minutes. Although it is not of practical use yet, I hope I can eventually build a good sidebox."; ?> If you have created these files for the packt template, you can try it by going to Tools | Layout Boxes Controller in the administration panel. From here, turn the sidebox ON and set it up to display in the left or the right side column. This sidebox will look like the following figure. Stylesheets All stylesheets for your new template should be placed in the /includes/templates/template_name/css folder. You should follow stylesheet naming conventions. It is a good idea to copy an old stylesheet and then modify it to suit your needs. You can have multiple stylesheets for your shop you can even add a stylesheet for each page. As a design rule, try to keep the declarations minimal, simple, and self explanatory. Try to restrain yourself from changing the class and ID names in the core files. Creating and Modifying Email Templates As a store owner, you need to send several mails to your existing and potential customers. All these emails use some templates that reside in the /email folder under the Zen Cart installation directory. To change these emails to your style, you may edit these templates. The email's structure is determined in one of two ways. If you are sending plain text emails, the email structure is determined by the way you put together the various items (customer greeting, order number, link to detailed invoice, and so on) in a string variable that is then passed to the zen_mail() function. If you are sending HTML emails, the structure is determined by the template you use. Text Email Template You can rearrange, add, or delete items in a plain text email. To do so, you will need to edit the Zen Cart files where the email is created. For example, if you want to edit the order confirmation email, you will need to edit the file includes/classes/order.php. In your example, open up includes/classes/order.php and scroll down to the bottom of the file, in the function send_order_email(). There, you will see the lines that construct the plain text email message: [Line 827]$email_order = EMAIL_TEXT_HEADER . EMAIL_TEXT_FROM . STORE_NAME . "nn" . $this->customer['firstname'] . ' ' . $this->customer['lastname'] . "nn" . EMAIL_THANKS_FOR_SHOPPING . "n" . EMAIL_DETAILS_FOLLOW . "n" . EMAIL_SEPARATOR . "n" . EMAIL_TEXT_ORDER_NUMBER . ' ' . $zf_insert_id . "n" . EMAIL_TEXT_DATE_ORDERED . ' ' . strftime(DATE_FORMAT_LONG) . "n" . EMAIL_TEXT_INVOICE_URL . ' ' . zen_href_link(FILENAME_ACCOUNT_HISTORY_INFO, 'order_id=' . $zf_insert_id, 'SSL' [Line 848]$email_order .= zen_db_output($this->info['comments']) . "nn";[Line 855]$email_order .= EMAIL_TEXT_PRODUCTS . "n" . EMAIL_SEPARATOR . "n" . $this->products_ordered . EMAIL_SEPARATOR . "n"; In this file, the variable that holds the plain text email message is called $email_order. It generally has a different name in each file, such as $email or $email_text. Whatever its name, this is the place where you will make your changes. You can add, delete, and rearrange the order of the items to suit your wishes. HTML Email Templates HTML Email templates have two parts: embedded CSS and HTML codes. You may be surprised to see the embedded stylesheet in each mail template, and may want to know why linked stylesheets have not been used. One reason for not using the linked stylesheet is that you may not know how the email clients will behave. Most email clients used today can handle HTML emails and stylesheets to some extent. But there is no guarantee that every customer will have an email client that can retrieve linked stylesheets and render the emails in the desired format. Stylesheets The first portion of the email template is devoted to defining styles for different parts of the mail. Open the /email/email_template_welcome.html file in your favorite text editor to examine the stylesheet in an email template. The stylesheet in this template will appear as follows: <style type="text/css">.body {background-color:#ffffff; color:#000000; font-family:Verdana, Arial, Helvetica, sans-serif;}....header {font-size:10px; padding:0px; width:550px;}.content {font-size:10px; padding:5px; width:550px;}.content-line {padding:5px;}.coupon-block { padding: 5px; border: 1px #cccccc solid; background-color: #FFFF99; }....disclaimer1 a:link {color:#666666;}.disclaimer1 a:visited {color:#666666;}.disclaimer2 { color: #666666; padding: 5px; }.copyright { border-bottom: 0px #9a9a9a solid; padding: 5px; }</style> Style declarations in this stylesheet are straight-forward. First, it has defined style for the body and hyperlinks. Then, it defines the content and email related styles. Most of the style names are self-explanatory. You will find the HTML blocks with these names in the template. HTML with variables The main part of the email template is the HTML code with style classes and variables. The following are some of the variables used to construct content for the email: $EMAIL_GREETING $EMAIL_WELCOME $COUPON_BLOCK $GV_BLOCK $EMAIL_MESSAGE_HTML $EMAIL_CONTACT_OWNER $EMAIL_CLOSURE $EMAIL_FOOTER_COPYRIGHT $EMAIL_DISCLAIMER $EMAIL_SPAM_DISCLAIMER $EXTRA_INFO These variables are defined in several PHP files, such as create_account.php. Once you have found the files that need to be edited, you may want to add a definition for your new HTML item to each one. For example, you have added an item called $EMAIL_HOURS_OF_OPERATION to the email_template_order_status.html template. One of the files that you will need to edit is admin/orders.php. Find the part of that file where the email message is being constructed. In this case, it begins around line 100. You can see that the HTML message is constructed with several statements such as: $html_msg['EMAIL_CUSTOMERS_NAME'] = $check_status->fields['customers_name'];$html_msg['EMAIL_TEXT_ORDER_NUMBER'] = EMAIL_TEXT_ORDER_NUMBER . ' ' . $oID; All you need to do is add a new statement under all of these, to define your new item: $html_msg['EMAIL_HOURS_OF_OPERATION'] = 'We are open from 9 AM to 5 PMevery day of the week.'; Use a $ in front of the name of your new item in the HTML template, but do not use the $ where you define it. To change the text displayed in your emails, edit the corresponding language file. You can change an existing text, or add a new one (if you've added it to your email structure). You add or change text values using the define() statements: define(EMAIL_LOVELY_YOU_DROPPED_BY,'We are just so immeasurably delighted that you stopped by our store today!'); There is another language file you need to modify when altering text for your emails, includes/languages/english/email_extras.php. This file contains several text strings common to all emails sent from your store. Summary Thus we have seen how to create new template using Zen Cart.   If you have read this article you may be interested to view : Integrating Zen Cart with Content Management Systems Installing Zen Cart Troubleshooting Zen Cart  

What and Why? Taxonomy is described as the science of classification. In terms of how it applies to Drupal, it is the method by which content is organized using several distinct types of relationship between terms. Simple as that! This doesn't really encompass how useful it is, though, but before we move on to that, there is a bit of terminology to pick up first: Term: A term used to describe content (also known as a descriptor) Vocabulary: A grouping of related terms Thesaurus: A categorization of content that describes is similar to relationships Taxonomy: A categorization of content into a hierarchical structure Tagging: The process of associating a term (descriptor) with content Synonym: Can be thought of as another word for the current term. It may help to view the following diagram in order to properly grasp how these terms inter-relate. This serves to illustrate the fact that there are two main types of vocabulary. Each type consists of a set of terms, but the relationships between them are different in that a taxonomy deals with a hierarchy of information, and a thesaurus deals with relationships between terms. The terms (shown as small boxes) and their relationships (shown as arrows) play a critical role in how content is organized. One of the things that makes the Drupal taxonomy system so powerful, is that it allows content to be categorized on the fly (as and when it is created). This unburdens administrators because it is no longer necessary to moderate every bit of content coming into the site in order to put it into pre-determined categories. We'll discuss these methods in some detail in the coming sections, but it's also worth noting quickly that it is possible to tag a given node more than once. This means that content can belong to several vocabularies, at once. This is very useful for cross-referencing purposes because it highlights relationships between terms or vocabularies through the actual nodes. Implementing Controlled Taxonomies in Drupal The best way to talk about how to implement some form of categorization is to see it in action. There are quite a few settings to work with and consider in order to get things up and running. Let's assume that the demo site has enlisted a large number of specialists who will maintain their own blogs on the website so that interested parties can keep tabs on what's news according to the people in the know. Now, some people will be happy with visiting their blog of choice and reading over any new postings there. Some people, however, might want to be able to search for specific topics in order to see if there are correlations or disagreements between bloggers on certain subjects. As there is going to be a lot of content posted once the site has been up and running for a few months, we need some way to ensure that specific topics are easy to find, regardless of who has been discussing them on their blogs. Introduction to Vocabularies Let's quickly discuss how vocabularies are dealt with in the administration tool in order to work out how to go about making sure this requirement is satisfied. If you click on the Taxonomy link under Content management, you will be presented with a page listing the current vocabularies. Assuming you have created a forum before, you should have something like this: Before we look at editing terms and vocabularies, let's take a look at how to create a vocabulary for ourselves. Click on the add vocabulary tab to bring up the following page that we can use to create a vocabulary, manually: By way of example, this vocabulary will deal with the topic of hunting. This vocabulary only applies to blog entries because that is the only content (or node) type for which it is enabled—you can select as many or as few as you like, depending on how many content types it should apply to. Looking further down the page, there are several other options that we will discuss in more detail, shortly. Clicking on Submit adds this vocabulary to the list, so that the main page now looks like this: So far so good, but this will not be of much use to us as it stands! We need to add some terms (descriptors) in order to allow tagging to commence. Dealing with Terms Click on add terms link for the Hunting vocabulary to bring up the following page: The term Trapping has been added here, with a brief description of the term itself. We could, if we choose, associate the term Poaching with Trapping by making it a related term or synonym (of course, you would need to create this term first in order to make it a related term). Click on the Advanced options link to expose the additional features, as shown here: In this case, the term Trapping is specified as being related to Poaching and by way of example, gin traps is a synonym. Synonyms don't actually do anything useful at the moment, so don't pay too much mind to them yet, but there are modules that expose additional functionality based on related terms and synonyms, such as the Similar by Terms module. The Parents option at the start of the Advanced options warrants a closer inspection, but as it relates more closely to the structure of hierarchies, we'll look at it in the section on Hierarchies that's coming up. For now, add a few more terms to this vocabulary so that the list looks something like this: It's now time to make use of these terms by posting some blog content. Posting Content with Categories Enabled Using any account with the requisite permissions to add blog content, attempt to post to the site. You should now be able to view the newly inserted Hunting category, as shown here: Now comes the clever bit! Once this blog node has been posted, users can view the blog as normal, except that it now has its term displayed along with the post (bottom right): Where does the descriptor link take us? Click on the term, in this case Canned hunting, and you will be taken to a page listing all of the content that has been tagged with this term. This should really have you quite excited, because with very little work, users can now find focused content without having to look that hard—this is what content management is all about!

External Commands Nagios offers a very powerful mechanism for receiving events and commands from external applications—the external commands pipe. This is a pipe file created on a file system that Nagios uses to receive incoming messages. The name of the file is rw/nagios.cmd and it is located in the directory passed as the localstatedir option during compilation. Following the compilation and installation instructions and the given guidelines, the file name will be /var/nagios/rw/ nagios.cmd. The communication does not use any authentication or authorization—the only requirement is to have write access to the pipe file. An external command file is usually writable by the owner and the group; the usual group used is nagioscmd. If you want a user to be able to send commands to the Nagios daemon, simply add that user to this group. A small limitation of the command pipe is that there is no way to get any results back and so it is not possible to send any query commands to Nagios. Therefore, by just using the command pipe, you have no verification that the command you have just passed to Nagios has actually been processed, or will be processed soon. It is, however, possible to read the Nagios log file and check if it indicates that the command has been parsed correctly, if necessary. An external command pipe is used by the web interface to control how Nagios works. The web interface does not use any other means to send commands or apply changes to Nagios. This gives a good understanding of what can be done with the external command pipe interface. From the Nagios daemon perspective, there is no clear distinction as to who can perform what operations. Therefore, if you plan to use the external command pipe to allow users to submit commands remotely, you need to make sure that the authorization is in place as well so that it is not possible for unauthorized users to send potentially dangerous commands to Nagios. The syntax for formatting commands is easy. Each command must be placed on a single line and end with a newline character. The syntax is as follows: [TIMESTAMP] COMMAND_NAME;argument1;argument2;...;argumentN TIMESTAMP is written as UNIX time—that is the number of seconds since 1970-01-01 00:00:00. This can be created by using the date +%s system command. Most programming languages also offer the means to get the current UNIX time. Commands are written in upper case. This can be one of the commands that Nagios should execute, and the arguments depend on the actual command. For example, to add a comment to a host stating that it has passed a security audit, one can use the following shell command: echo "['date +%s'] ADD_HOST_COMMENT;somehost;1;Security Audit;This host has passed security audit on 'date +%Y-%m-%d'">/var/nagios/rw/nagios.cmd This will send an ADD_HOST_COMMENT command (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php? command_id=1) to Nagios over the external command pipe. Nagios will then add a comment to the host, somehost, stating that the comment originated from Security Audit. The first argument specifies the host name to add the comment to; the second tells Nagios if this comment should be persistent. The next argument describes the author of the comment, and the last argument specifies the actual comment text. Similarly, adding a comment to a service requires the use of the ADD_SVC_COMMENT command (visit http://www.nagios.org/developerinfo/externalcommands/ commandinfo.php? command_id=1) . The command's syntax is very similar to the ADD_HOST_COMMENT command except that the command requires the specification of the host name and service name. For example, to add a comment to a service stating that it has been restarted, you should use the following echo "['date +%s'] ADD_SVC_COMMENT;router;OpenVPN;1;nagiosadmin;Restarting the OpenVPN service" >/var/nagios/rw/nagios.cmd The first argument specifies the host name to add the comment to; the second is the description of the service to which Nagios should add the comment. The next argument tells Nagios if this comment should be persistent. The fourth argument describes the author of the comment, and the last argument specifies actual comment text. You can also delete a single comment or all comments using the DEL_HOST_ COMMENT (visit http://www.nagios.org/developerinfo/externalcommands/ commandinfo.php? command_id=3), DEL_ALL_HOST_COMMENTS (visit http://www. nagios.org/developerinfo/externalcommands/commandinfo.php? command_ id=13), and DEL_SVC_COMMENT (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php? command_id=4) or DEL_ALL_SVC_COMMENTS commands (visit http://www.nagios.org/developerinfo/externalcommands/ commandinfo.php? command_id=14). Other commands worth mentioning are related to scheduling checks on demand. Very often, it is necessary to request that a check be carried out as soon as possible; for example, when testing a solution. This time, let's create a script that schedules a check of a host, all services on that host, and a service on a different host, as follows: #!/bin/shNOW='date +%s'echo "[$NOW] SCHEDULE_HOST_CHECK;somehost;$NOW" >/var/nagios/rw/nagios.cmdecho "[$NOW] SCHEDULE_HOST_SVC_CHECKS;somehost;$NOW" >/var/nagios/rw/nagios.cmdecho "[$NOW] SCHEDULE_SVC_CHECK;otherhost;Service Name;$NOW" >/var/nagios/rw/nagios.cmdexit 0 The commands SCHEDULE_HOST_CHECK (visit http://www.nagios.org/ developerinfo/externalcommands/commandinfo.php? command_id=127) and SCHEDULE_HOST_SVC_CHECKS (http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=30) accept a host name and the time at which the check should be scheduled. The SCHEDULE_SVC_CHECK command (visit http://www.nagios.org/developerinfo/externalcommands/ commandinfo.php? command_id=29) requires the specification of a service description as well as the name of the host to schedule the check on. Normal scheduled checks, such as the ones scheduled above, might not actually take place at the time that you scheduled them. Nagios also needs to take allowed time periods into account as well as checking whether checks were disabled for a particular object or globally for the entire Nagios. There are cases when you'll need to force Nagios to do a check—in such cases, you should use SCHEDULE_FORCED_HOST_CHECK (visit http://www.nagios. org/developerinfo/externalcommands/commandinfo.php? command_id=128), SCHEDULE_FORCED_HOST_SVC_CHECKS (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php? command_id=130) and SCHEDULE_FORCED_SVC_CHECK (visit http://www.nagios.org/developerinfo/ externalcommands/commandinfo.php? command_id=129) commands. They work in exactly the same way as described above, but make Nagios skip the checking of time periods, and ensure that the checks are disabled for this particular object. This way, a check will always be performed, regardless of other Nagios parameters Other commands worth using are related to custom variables, introduced in Nagios 3. When you define a custom variable for a host, service, or contact, you can change its value on the fly with the external command pipe. As these variables can then be directly used by check or notification commands and event handlers, it is possible to make other applications or event handlers change these attributes directly without modifications to the configuration files. A good example would be that the IT staff registers its presence via an application without any GUI. This application periodically sends information about the latest known IP address, and that information is then passed to Nagios assuming that the person is in the office. This would later be sent to a notification command to use that specific IP address while sending a message to the user. Assuming that the user name is jdoe and the custom variable name is DESKTOPIP, the message that would be sent to the Nagios external command pipe would be as follows: [1206096000] CHANGE_CUSTOM_CONTACT_VAR;jdoe;DESKTOPIP;12.34.56.78 This would cause a later use of $_CONTACTDESKTOPIP$ to return a value of 12.34.56.78. Nagios offers the CHANGE_CUSTOM_CONTACT_VAR (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php? command_id=141), CHANGE_CUSTOM_HOST_VAR (visit http://www.nagios.org/developerinfo/ externalcommands/commandinfo.php?command_id=139), and CHANGE_CUSTOM_ SVC_VAR (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=140) commands for modifying custom variables in contacts, hosts and, services accordingly. The commands explained above are just a very small subset of the full capabilities of the Nagios external command pipe. For a complete list of commands, visit http:// www.nagios.org/developerinfo/externalcommands/commandlist.php, where the External Command List can be seen. External commands are usually sent from event handlers or from the Nagios web interface. You will find external commands most useful when writing event handlers for your system, or when writing an external application that interacts with Nagios. Event Handlers Event handlers are commands that are triggered whenever the state of a host or  service changes. They offer functionality similar to notifications. The main difference is that the event handlers are called for each type of change and even for each soft state change. This provides the ability to react to a problem before Nagios notifies it as a hard state and sends out notifications about it. Another difference is what the event handlers should do. Instead of notifying users that there is a problem, event handlers are meant to carry out actions automatically. For example, if a service defined with max_check_attempts set to 4, the retry_ interval set to 1, and the check_interval is set to 5, then the following example illustrates when event handlers would be triggered, and with what values, for $SERVICESTATE$, $SERVICESTATETYPE$, and $SERVICEATTEMP$ macro definitions: Event handlers are triggered for each state change—for example, in minutes, 10, 23, 28, and 29. When writing an event handler, it is necessary to check whether an event handler should perform an action at that particular time or not. See the following example for more details. A typical example might be that your web server process tends to crash once a month. Because this is rare enough, it is very difficult to debug and resolve it. Therefore, the best way to proceed is to restart the server automatically until a solution to the problem is found. If your configuration has max_check_attempts set to 4, as in the example above, then a good place to try to restart the web server is after the third soft failure check—in the previous example, this would be minute 12. Assuming that the restart has been successful, the diagram shown above would look like this: Please note that no hard critical state has occurred since the event handler resolved the problem. If a restart cannot resolve the issue, Nagios will only try it once, as the attempt is done only in the third soft check. Event handlers are defined as commands, similar to check commands. The main difference is that the event handlers only use macro definitions to pass information to the actual event handling script. This implies that the $ARGn$ macro definitions cannot be used and arguments cannot be passed in the host or service definition by using the ! separator. In the previous example, we would define the following command: define command{command_name restart-apache2command_line $USER1$/events/restart_apache2$SERVICESTATE$ $SERVICESTATETYPE$ $SERVICEATTEMPT$} The command would need to be added to the service. For both hosts and services, this requires adding an event_handler directive that specifies the command to be run for each event that is fired. In addition, it is good to set event_handler_enabled set to 1 to make sure that event handlers are enabled for this object. The following is an example of a service definition: define service{host_name localhostservice_description Webserveruse apacheevent_handler restart-apache2event_handler_enabled 1} Finally, a short version of the script is as follows: #!/bin/sh# use variables for argumentsSERVICESTATE=$1SERVICESTATETYPE=$2SERVICEATTEMPT=$3# we don't want to restart if current status is OKif [ "$SERVICESTATE" != "OK" ] ; then# proceed only if we're in soft transition stateif [ "$SERVICESTATETYPE" == "SOFT" ] ; then# proceed only if this is 3rd attempt, restartif [ "$SERVICESTATEATTEMPT" == "3" ] ; then# restarts Apache as system administratorsudo /etc/init.d/apache2 restartfififiexit 0 As we're using sudo here, obviously the script needs an entry in the sudoers file to allow the nagios user to run the command without a password prompt. An example entry for the sudoers file would be as follows: nagios ALL=NOPASSWD: /etc/init.d/apache2 This will tell sudo that the command /etc/init.d/apache2 can be run by the user nagios and that asking for passwords before running the command will not be done. According to our script, the restart is only done after the third check fails. Assuming that the restart went correctly, the next Nagios check will notify that Apache is running again. As this is considered a soft state, Nagios has not yet sent out any notifications about the problem If the service would not restart correctly, the next check will cause Nagios to set this failure as a hard state. At this point, notifications will be sent out to the object owners. You can also try performing a restart in the second check. If that did not help, then during the third attempt, the script can forcefully terminate all Apache2 processes using the killall or pkill command. After this has been done, it can try to start the service again. For example: # proceed only ifthis is 3rd attempt, restartif [ "$SERVICESTATEATTEMPT" == "2" ] ; then# restart Apache as system administratorsudo /etc/init.d/apache2 restartfi# proceed only ifthis is 3rd attempt, restartif [ "$SERVICESTATEATTEMPT" == "3" ] ; then# try to terminate apache2 process as system administratorsudo pkill apache2# starts Apache as system administratorsudo /etc/init.d/apache2 startfi Another common scenario is to restart one service if another one has just recovered—for example, you might want to restart email servers that use a database for authentication if the database has just recovered from a failure state. The reason for doing this is that some applications may not handle disconnected database handles correctly—this can lead to the service working correctly from the Nagios perspective, but not allowing some of the users in due to internal problems. If you have set this up for hosts or services, it is recommended that you keep flapping enabled for these services. It often happens that due to incorrectly planned scripts and the relations between them, some services might end up being stopped and started again. In such cases, Nagios will detect these problems and stop running event handlers for these services, which will cause fewer malfunctions to occur. It is also recommended that you keep notifications set up so that people also get information on when flapping starts and stops. Modifying Notifications An interesting new feature in Nagios 3 is the ability to change various parameters related to notifications. These parameters are modified via an external command pipe, similar to a few of the commands shown in the previous section. A good example would be when Nagios contact persons have their workstations connected to the local network only when they are actually at work (which is usually the case if they are using notebooks), and turn their computers off when they leave work. In such a case, a ping check for a person's computer could trigger an event handler to toggle that person's attributes. Let's assume that our user jdoe has two actual contacts—jdoe-email and jdoejabber, each for different types of notifications. We can set up a host corresponding to the jdoe workstation. We will also set it up to be monitored every five minutes and create an event handler. The handler will change the jdoe-jabber's host and service notification time period to none on a hard host down state. On a host up state change, the time period for jdoe-jabber will be set to 24x7. This way, the user will only get Jabber notifications if he or she is at work. Nagios offers commands to change the time periods during which a user wants to receive notifications. The commands for this purpose are: CHANGE_CONTACT_HOST_ NOTIFICATION_TIMEPERIOD ( http://www.nagios.org/developerinfo/ externalcommands/commandinfo.php? command_id=153 ) and CHANGE_CONTACT_ SVC_NOTIFICATION_TIMEPERIOD ( http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=152 ). Both commands take the contact and the time period name as their arguments. An event handler script that modifies the user's contact time period based on state is as follows #!/bin/shNOW='date +%s'CONTACTNAME=$1-jabberif [ "$2,$3" = "DOWN,HARD" ] ; thenTP=noneelseTP=24x7fiecho "[$NOW] CHANGE_CONTACT_HOST_NOTIFICATION_TIMEPERIOD;$CONTACT;$TP" >/var/nagios/rw/nagios.cmdecho "[$NOW] CHANGE_CONTACT_SVC_NOTIFICATION_TIMEPERIOD;$CONTACT;$TP" >/var/nagios/rw/nagios.cmdexit 0 The command should pass $CONTACTNAME$, $SERVICESTATE$, and $SERVICESTATETYPE$ as parameters to the script. In case you need a notification about a problem sent again, you should use the SEND_CUSTOM_HOST_NOTIFICATION or SEND_CUSTOM_SVC_NOTIFICATION command. These commands take host or host and service names, additional options, author name, and comments that should be put in the notification. Options allow specifying if the notification should also include all escalation levels (a value of 1), if Nagios should skip time periods for specific users (a value of 2) as well as if Nagios should increment notifications counters (a value of 4). Options are stored bitwise so a value of 7 (1+2+4) would enable all of these options. The notification would be sent to all people including escalations; it will be forced, and the escalation counters will be increased. Option value 3 means it should be broadcast to all escalations as well, and the time periods should be skipped. To send a custom notification about the main router to all users including escalations, you should send the following command to Nagios [1206096000] SEND_CUSTOM_HOST_NOTIFICATION;router1;3;jdoe;RESPOND ASAP

We are going to carry out a role-play activity. This activity will be geography-based, but the Moodle activities are the same for any subject. Hopefully, this will help you gain some ideas for your own teaching. Having learned about the course of a river and about the landscape at the location where the river meets the coast, the students are now going to be given the job of developers—planning and designing a riverside campsite. The students will undertake various tasks during the project, all of them within Moodle. We, the teachers, having set the scene, are going to sit back and observe their progress, online. When the entire mini-project is complete, we're going to get them to tell us, personally, how much they feel they have learned. We can use their responses to plan our future Moodle activities. How do we do all this? The words in bold above are examples of activities that we can do in Moodle. There are others too, but for you—as a newbie—these activities are more than enough. To set up any of them, we first need to turn editing on, either via the button on the upper right of the screen, or via the Administration block. Then, in the topic section where we want to add our activity, we click on the space next to Add an activity…. This will bring up a list of options, which might vary depending upon your particular Moodle course. The following screenshot shows some typical options that might show up when you click Add an activity....Be aware that Certificate and Game don't appear in standard Moodle courses. Getting our class to reflect and discuss Have you ever come across a child who is too shy to speak up in class but then produces the most thoughtful written work? Moodle is Godsend for these students, because it has a forum and a chat facility, both of which enable classes and their teachers to have a discussion without actually being together, in the same room. And often, the shy child will happily have their say online, where they can plan it out first and feel comfortable without the interference of their peers. We're going to set some homework where the students will discuss, in general, the kinds of things to keep in mind when planning a riverside campsite. Hopefully, someone will realize it's not a good idea to have it too close to the water. Time for action-setting up a discussion forum on Moodle Let's create an online discussion area for the students to share their views and comments. This discussion area is called the Forum. With editing turned on, click on Add an activity and select Forum. As a result, the following information will appear on the screen. In the Forum type field, click on the drop-down arrow and choose Single Simple Discussion (we'll investigate on the other options later). In the Forum name field, enter some text that will invite your students to click on it to join the discussion. In the Message field, enter your starting topic, with images and hyperlinks, if you wish. Change the option Force everyone to be subscribed to Yes, if you want people to get an email every time somebody adds their comments or suggestions to the forum. Leave the option Read tracking as it is, and people can decide whether to track read or unread messages. The option, Maximum attachment size lets you decide how big a file or an image people can attach with a message. Grade—alter these settings to give each post a mark. But be aware that this will put younger children off. You can put a number in the Post threshold for blocking option if you want to limit the number of posts that a student can make. Click on Save and return to course. What just happened? We have just set up an online discussion area (forum) on a specific topic for our class. Let's go back to our course page and click on the forum that we just prepared. The final output will look like this: Our students will see an icon (usually with two faces) that will prompt them to join the preliminary discussion on where best to locate the campsite. They'll click on the Reply link at the bottom (as you can see in the preceding screenshot), to post their response. How do we moderate the forum? Hopefully, we can just read the students' responses and let them discuss the topic amongst themselves. But as a teacher, we do have three other options: We can edit the response posted by the student (change the wording if it's inappropriate). We can delete the post altogether. We can reply to it when we think it is really important to do so. A student only has the option to reply (as you see if you click on Student view at the upper right of the course page). When we need to get rid of an unsuitable post, or perhaps alter the wording of something one of our students has typed, this extra power we teachers have is helpful. For our starter discussion, we chose a Single Simple Discussion as we wanted the students to focus totally on one issue. However, in other situations, you might need a slightly different type of forum. So the following table gives a brief overview of the other kinds that are available, and explains how you could use them: Name What it does Why use it Single Simple Discussion Only one question they can all answer Best for focused discussions-they can't get distracted Standard forum  Everyone can start a new topic More scope for older students Q and A Pupils must answer first before they can see any replies Useful for avoiding peer pressure issues Each person posts 1 discussion Pupils can post ONE new topic only Handy if you need to restrict posting but still allow some freedom Why use a forum? Here are a few other thoughts on forums, based on my own experiences: A cross-year or cross-class forum can be useful, as the older students can pass on their experiences to the younger students. For example, each year my first year high school students make a volcano as a homework project. As they enter their second year, they use a dedicated forum to pass on their wisdom and answer technical questions sought by the inexperienced first-year students—who are about to begin their own creations. A homework exercise could be set on a forum, as a reflective plenary to the learning done in the class. Once, my class watched a documentary based on the Great New Orleans flood of 2004, and the students were asked, on a forum, to imagine they had been there. They had to suggest some words or phrases to describe their feelings—which we then collated into the next lesson to make poems about the flood. Let's add a little bit of confusion. Instead of simply asking a question, why not make a statement that you know will inspire, annoy, and divide the students. As a result, you can see the variety in the responses. I once posted the topic: “If people live near rivers, and their homes get flooded out, it is surely their own fault for living near rivers. Why should the rest of us have to help them?” In response to this, some violently disagreed with the statement—quoting examples from developing countries, whereas some agreed with the statement—and were then blasted down by their classmates for doing so. But at least the forum got visited! Carrying on the conversation in real time—outside of school A discussion forum, as illustrated above, is a useful tool to get the children to think and to contribute their ideas. It has an advantage over the usual class discussion, in that the shyer pupils are more likely to open up in such discussion forums. However, there is no spontaneity involved. You might post a comment in the morning, and the response may arrive at dinnertime, and so on. Why not combine the advantages of online communication with the advantages of a real time conversation, and make a Moodle chat room? If your students live several miles away from each other, as my students do, and are keen to get on with the project, Moodle chat rooms can have real benefits. We can set a time for the chat—say, Saturday afternoon. This would be a time when we can be present too, if we wish, and the students can move ahead with their plans even though they're not with each other in the classroom. Even though this implementation has its own drawbacks, it provides us with a set-up. Eventually, we can see how it goes and then think about how best we can use it. Time for action-setting up a chat room in Moodle Let's create a chat room where the students can have a chat even when they are not in the same classroom. This way, they can share their views, comments, and suggestions. With editing turned on, go to Add an activity, and select the Chat option. In the Name of this chat room field, enter an appropriate title for the discussion. In the Introduction text field, type in what the discussion is going to be about. For the Next chat time option, choose when you want to open the chat room. For the Repeat sessions option, choose whether you want to chat regularly, or just once. For the Save past sessions option, choose how long, if at all, to keep a record of the conversation. It is up to you to decide whether to allow everyone to view the past sessions or not. For now, you can ignore the Common module settings option. Click on Save and Display. What just happened? We have set up the place and time on Moodle for our students to talk to each other—and even with us if necessary—online. Students will see an icon—usually a speech bubble—on the course page, alongside the name given to the chat. The students just have to click on the icon at the correct time for the chat. When the room is open, they will see this: Clicking on the link will take the students to a box where they'll be able to see their user photo (if they have one) and the time at which they have entered the chat. When others join in, their photos will be shown, and the time of their arrival will be recorded. You talk by typing into the long box at the bottom of the screen, and when submitted, your words appear in the larger box above it. This can get quite confusing if a lot of people are typing at the same time, as the contributions appear one under the other, and do not always follow on from the question or response to which they are referring. Why use Chat? (and why not?) I have to confess that I have switched off the ability for people to use Chat on my school's Moodle site. Chat does have one advantage over the Forum, which is that you can hold discussions in real time with the others who are not physically present in the same room as you. This could be useful on occasions, such as when the teacher is absent from school (but available online). He or she can contact the class at the start of the lesson to check whether they know what they are doing. The students in our school council use Chat for meetings out of school hours, as do our school Governors. You can also read the transcript of a chat (the chat log) after it has happened. However, everyone really has to stay focused on the discussion topic, otherwise, you risk having nothing but a list of trite comments, and no real substance. I've found this to be the case with younger children. Personally, I find a single and a simple discussion in a Forum to be of much more value, than Chat. However, you can try using Chat and see what you think. Your experience could be different from mine.