Search code examples
c#visual-studio-2017odata

How to Consume an OData v3.0 Service within Visual Studio 2017

I am struggling to find a way to simply use a OData v3.0 service in any way from within Visual Studio 2017, so I can use the Client library to help develop my app/service to consume the data.

According to the Microsoft OData Stack page, they seem to have all of the tools and support to consume an OData v4.0 service. Not knowing I was in fact dealing with a v3.0 service, I followed these instructions and as the page describes, there are two tooling options to get you started. One is the OData Client Code Generator, and the other is the OData Connected Service extensions

After having to go thru some hoops to even get either one to work (see GitHub Issue for actually finding a version of the Client Code Generator that actually works with VS2017, and and trying a work around to get the OData Connected Service to work with a service that requires authentication, I finally realized I was working with an OData v3.0 response. So these tools couldn't help.

Now contradictory to what is actually mentioned on the OData Connected Service marketplace page, where is says "OData Connected Service for V1-V4", this did not work. If the OData service requires authentication, then I get this error dialog from trying to add a Connected Service via the extension:

Error when trying to add OData Service that requires Auth with Connected Servcie and extension

So then I read in a GitHub issue (can't find it), is that a potential work around is to download the XML that is returned from hitting the /$metadata endpoint, rename it to whatever.edmx and try to use that for the extension by providing a file:// URI to that file. That didn't work with the following error dialog:

enter image description here

So then I ditched that approach and tried to instead use the Client Code Generator, and providing the edmx file to that in the TT config (to solve the auth issues, and that didn't work because it was OData v3.0 and not 4.0.

So then, it seems for v3.0, the approach is to use Add Service Reference, but when I do that, I get the following error:

enter image description here

..but that tool doesn't support v3.0.. so now I have no idea how to proceed!?

Any help would be greatly appreciated!

Solution

  • Just in case someone else stumbles on this particular combination and can't seem to proceed with consuming an OData v3.0 service with current VS2017, (and specifically on how to use it in an Azure Function), here is what I did to get around this:

    1. Reinstall VS2015 and create a new library project
    2. Add a new Service Reference and point to your OData v3 (or earlier) service. if the service requires authentication, this dialog will allow you to enter the creds. I was prompted to enter them 2x.
    3. Create a class / service / interface that will expose all of the relevant tables / queries that you are interested in consuming from that OData service
    4. Save the project and close VS2015
    5. Copy this project to your VS2017 solution. In my case, I had a solution containing an Azure Function.
    6. Now call upon this new project/library to obtain the data.

    This is the only way I could get this to work after many many hours of troubleshooting various limitations and workarounds of the current versions. Needless to say, I am quite disappointed in the current state of the tooling + VS2017's support for consuming older versions of OData.