Sunday, July 5, 2009

Setting up a development environment for iWidgets with RAD 7.5

About a month ago I started to look at how to develop iWidgets for the IBM Mashup Center 1.1. I come from a J2EE WAR based programming background so was interested on how to configure my Eclipse based tooling to develop iWidget in the easiest way possible.

The following steps worked for me and allowed a very quick edit, save, publish, test cycle where I could edit the iWidget code and have it running in my browser in seconds. IMC 1.1 does support OSGi packaged iWidgets I will look into that next time.

Steps

When developing iWidgets for IBM Mashup Center (IMC), rather than repeatedly create and deploy new WAR files to IMC, it is possible to configure RSA/RAD 7.x such that the WAR files you are developing can be integrated with the IMC runtime from your workspace. This way, you can simply modify and test any changes by reloading the Lotus Mashups page in the browser. The following steps are required.

Create a WAS 6.1 server configuration for RSA/RAD that points at the WAS installation for IMC. If you installed IMC in the directory C:IMC for example, you will need to configure a runtime pointing at the directory C:IMCAppServer.
Use the RMI connector to make the server attachment, RSA/RAD should suggest the correct port for you to use for your connector e.g 2811. You should now be in a position to deploy assets from your workspace into the IMC WAS installation.
Create a Dynamic Web Project to contain your new iWidget together with an EAR in which to contain the resulting WAR. This is the container into which you put the contents of your widget together with the required deployment descriptors and so on.A description of what these look like can be found in the Lotus Mashups help pages together with the details of the iWidget programming guide. A simple iWidget WAR is attached to this page by way of an example.
Add the new EAR file to the server configuration you created earlier. It should now be available via the IMC WAS application server. You can test this by requesting the URL of the XML manifest for your iWidget using your browser — it should be visible through the newly deployed WAR file e.g.
http://localhost:9082/CardReader/CardReader.xml
where CardReader is the name of the WAR file.

Stop the IMC WAS instance using the RSA/RAD Servers controls.
With IMC stopped, we now need to edit the Catalog file so that the widget we are developing appears on one of the drop down menus in the Lotus Mashups editor page. This provides the linkage between the Lotus Mashups environment and our workspace widget. Look within your IMC installation for the file called catalog_admin.xml which if you have installed into C:IMC will be found in C:IMCmmpubliccat. Make a backup copy of this file.
Open the catalog_admin.xml file in WordPad. You will see it is organised into a hierarchy of categories and entries.
Copy an entry element and its contents and paste a copy within one of the category elements. Easiest option is simply to paste it below the entry that you just copied.
Modify the entry to contain a meaningful name, description and id and unique-name values on the entry element. No matter how strong the urge DO NOT REFORMAT THE XML. Preserve the original formatting.
Set the contents of the definition tag within the entry tag to the URI of your XML manifest. This links the menu item to your specific widget e.g.
/CardReader/CardReader.xml
to continue the above example.

Save the XML file.
Restart the IMC WAS runtime from RSA/RAD.
Load Lotus Mashups in your browser and login.
You may see a JavaScript dialog box containing the message “TypeError - 103e is null.” Simply press OK and then the reload button your browser.
You should now see the Lotus Mashups Welcome Page as usual.

Press the Go to View button on the Welcome Page. You will see a set of tabs appear containing the categories you saw earlier in the catalog XML file.

Find the category into which you added your widget earlier. You should now be able to drag your widget from the menu onto the Lotus Mashups page.

Now, when you make changes to the widget in RSA/RAD, you can pick them up simply by reloading the Lotus Mashups page. When your widget is ready, you then deploy it by exporting the WAR file.