This approach of being able to invoke WCF services from within the CRM UI we give us many useful features that can be used to extend CRM.
- Implement custom WCF services that are designed to be used by the CRM UI. Thus making the least number of calls as possible and only retrieving the required data.
- The ability to implement very complex logic in the helper service that could include talking to CRM SDK services, Third party services or databases.
- Easy to maintain as operations can be altered/added/removed with minimal effort. There is no need to update any proxy scripts as they get generated at runtime.
The implementation consists of a custom web application deployed under the ISV directory on the CRM website. The web application will host the custom helper WCF service and provide all the scripts and customisations required to invoke the WCF service from a CRM form. The first step is to implement the WCF service. This will be implemented as a standard .NET library. I will not go into the details of the implementation of the WCF service as it is outside the scope of this post. Below is the code for the sample WCF service.
The next step is to host the service in our custom web application. To do that add the reference to the previously created library and then create a new “Services” directory in the web application. Then add two files. The first file is “JSService.svc” which is the base endpoint address for the service. Below are the contents of the file.
To finish the service setup also add a web.config file to the same directory that includes the configuration for the WCF Service. The service will use windows authentication. However when you host the web application in IIS make sure you enable anonymous access on the “Services” directory to allow access to the metadata endpoint. You can also enable anonymous access on the script files to speed up loading time performance. Note the endpoint behavior that enables the endpoint to be accessible using AJAX.
Finally the last and easiest step is to load the script and execute it from the CRM UI. For demonstration purposes i will just call the service on the load event. However you can call this code from anywhere you like. The code below needs to be added to “OnLoad” event for the CRM form. If everything is step up properly you should see a popup when you open the CRM form.
As you can see once everything is setup, making calls to the WCF service is just a matter of calling a method and processing the response. I have created a sample that includes all the required files and test pages. The sample demonstrates the concepts in this post and provides you with a working example. However note that if you decide to run the sample locally in visual studio you will have to configure the web application to run under IIS instead of the visual studio built-in web server. Otherwise you will get an error indicating that Windows Authentication is not supported. Hope you find this post useful.
You can download the sample code from here.