RIA Services vs ADO.NET Data Services

Your proposal architecture with the silverlight app calling both WCF Services and Ria services sounds fair to me.

Suppose your DB has an Employee Entity.

I can get this approach up and running, but have some issues

• Suppose "the WCF biz service" accesses and modifies Employee.
  • does it get this data from the database directly? (if so, is the EntityFramework edmx model shared between "the WCF biz service" and ria?)
  • does it in turn uses the RIA layer, and thus the EmployeeRiaProxy?
  • ..?
    
    
• Suppose you want to use the Employee Entity on your "WCF biz service" operation contract
  • This should not be possible in a pure SOA architecture?
  • Use a pure DTO data contract style approach with an EmployeeDto?
  • Should you use the Employee, or the EmployeeRiaProxy?
    • Using the Employee is not possible because the silverlight app does not know it (or would cause another EmployeeWCFProxy type being created on the client)
    • Using the EmployeeRiaProxy is possible, but ties your operation contract to a Ria proxy (pretty poor design) and assumes the service uses RIA for data access

Or should everything pass through this RIA layer? from which you call "the WCF biz service" in turn then?

Any opinions welcome!

Koen

I'm not sure I understand the full breadth of your problem, but at the very least, I would make sure I had a clientaccesspolicy.xml file and a crossdomain.xml file in the root folder of the service. It's important for the xml policy files to be in the root folder of the domain. For example, if your service is hosted in mycompany.com/services, the xml files need to be in the mycompany.com folder, not the services folder.

Here's an example of the ClientAccessPolicy.xml:

<?xml version="1.0" encoding="utf-8" ?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from http-request-headers="*">
        <domain uri="*"/>
      </allow-from>
      <grant-to>
        <resource include-subpaths="true" path="/"/>
      </grant-to>
    </policy>
  </cross-domain-access>
</access-policy>

And here's an example of the crossdomain.xml:

<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
    <allow-http-request-headers-from domain="*" headers="*" />
</cross-domain-policy>

I would recommend using both files for both flash and silverlight. Both files above will allow open access from all flash and silverlight apps, but that shouldn't be a problem if you're behind a firewall.

I had this exact problem in one of my behind-the-firewall silverlight apps and putting these files in place seemed to fix the problem. I would start with these files and go from there.