UPDATE Oct. 8th, 2011:
VMware Labs published the Perspectives-Plugin!
This is an very smart way to provide certain users a Web-Interface for certain workflows in a very easy way (and without any need for development, you just have to run the setup workflows)…
Download the Perspectives-Plugin here: http://labs.vmware.com/flings/perspectives-plug-in-for-vcenter-orchestrator
More information and configuration examples on www.vcoteam.info
*** Original Post ***
Right now, the Orchestrator provides two ways to create a web-based frontend. You can use the built-in components named Webviews, or you can do your own stuff using the SOAP-Webservice-API of vCO.
Webviews are based on Tapestry (a web-framework to “connect” HTML-Elements and Java-Classes) and Dojo (mainly for the input presentation of workflows).
There is one ready-to-run Webview bundled with vCO: the weboperator. It provides easy-to-use access to all workflows, you can run, monitor and schedule workflows via browser. The weboperator is installed automatically, but you have to publish it once:
After that you can access the weboperator via your Browser: http://your.vco.server:8280/vmo/weboperator
If you want to develop your own webviews, start with the template in the examples.zip you can download from the vCO-homepage https://www.vmware.com/support/orchestrator/doc/vco-samples-4.1.0-776.zip and the corresponding documentation in the Developer Guide (page 279) http://www.vmware.com/pdf/vco_410_developers_guide.pdf#page=279
Good luck 😛 !
For using the SOAP-based Webservice-API you can find the process also in the Developer Guide:
There are a bunch of examples for different programming languages:
Java and C#: See the examples.zip (link above)
Powershell: Calling Workflows from Powershell
There are two real challenges when using the webservice-API: If your workflow hast input parameters, especially ones from the Inventory (like a VM), you have to other calls to find them, and there is currently no support for the input presentation defined in the workflow (in rare cases, where some “business-logic” is done via input presentation it might be possible that you cannot use these workflows via the API!).
To conclude: Having a web-based User Interface for vCO is a very useful thing, because you can let end-users execute workflows directly. There are a couple of mechanisms available to create such web-GUIs, and some promising components are on the way (VMware aquired Wavemaker, Rumors about FLEX-based vSphere Client, … 😉 )