0
votes

I am using OData V3 endpoints using asp.net with webapi 2.2. I have successfully implemented CRUD operation with it. Now, I would like to add some custom actions along with CRUD operations. I have followed the article ( http://www.asp.net/web-api/overview/odata-support-in-aspnet-web-api/odata-v3/odata-actions ) to create the action with OData V3 with web api.

When I type

URI:

http://localhost:55351/odata/Courses(1101)/AlterCredits

it throws following error:

<m:error><m:code/><m:message xml:lang="en-US">No HTTP resource was found that matches the request URI 'http://localhost:55351/odata/Courses(1101)/AlterCredits'.</m:message><m:innererror><m:message>No routing convention was found to select an action for the OData path with template '~/entityset/key/unresolved'.</m:message><m:type/><m:stacktrace/></m:innererror></m:error>

I have also tried adding a custom route convetion for non-bindable actions. (https://aspnet.codeplex.com/SourceControl/latest#Samples/WebApi/OData/v3/ODataActionsSample/ODataActionsSample/App_Start/WebApiConfig.cs ) Not sure if I have to use this.

Here is my code:

WebApiConfig.cs :---

namespace ODataV3Service
{
public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        IList<IODataRoutingConvention> conventions = ODataRoutingConventions.CreateDefault(); //Do I need this?
        //conventions.Insert(0, new NonBindableActionRoutingConvention("NonBindableActions"));

        // Web API routes                        
        config.Routes.MapODataRoute("ODataRoute","odata", GetModel(), new DefaultODataPathHandler(), conventions);
    }

    private static IEdmModel GetModel()
    {
        ODataModelBuilder modelBuilder = new ODataConventionModelBuilder();
        modelBuilder.ContainerName = "CollegeContainer";
        modelBuilder.EntitySet<Course>("Courses");
        modelBuilder.EntitySet<Department>("Departments");

        //URI: ~/odata/Course/AlterCredits
        ActionConfiguration atlerCredits = modelBuilder.Entity<Course>().Collection.Action("AlterCredits");
        atlerCredits.Parameter<int>("Credit");
        atlerCredits.Returns<int>();

        return modelBuilder.GetEdmModel();
    }
  }
}

CoursesController.cs:----

[HttpPost]        
    //[ODataRoute("AlterCredits(key={key},credit={credit})")]
    public async Task<IHttpActionResult> AlterCredits([FromODataUri] int key, ODataActionParameters parameters)
    {            
        if (!ModelState.IsValid)
            return BadRequest();

        Course course = await db.Courses.FindAsync(key);
        if (course == null)
        {
            return NotFound();
        }

        int credits = course.Credits + 3;

        return Ok(credits);
    }

Global.asax:----

namespace ODataV3Service
{
 public class WebApiApplication : System.Web.HttpApplication
 {
    protected void Application_Start()
    {
        GlobalConfiguration.Configure(WebApiConfig.Register);
    }
 }
}

I have done research online and found this link. Web API and OData- Pass Multiple Parameters But this one is for OData V4. I am using OData V3 and Action.

Thanks,

1

1 Answers

1
votes

First, your action AlterCredits is defined as:

ActionConfiguration atlerCredits = modelBuilder.Entity<Course>().Collection.Action("AlterCredits");

It means AlterCredits bind to the collection of Course.

Second, your method AlterCredits in your controller is defined as:

public async Task<IHttpActionResult> AlterCredits([FromODataUri] int key, ODataActionParameters parameters)
{
...
}

It means AlterCredits listen to the call on the entity of Course.

Therefore, you got the No HTTP resource was found error message.


Based on your sample code, I create a sample method for your reference:

[HttpPost]
public async Task<IHttpActionResult> AlterCredits(ODataActionParameters parameters)
{
    if (!ModelState.IsValid)
        return BadRequest();

    object value;
    if (parameters.TryGetValue("Credit", out value))
    {
        int credits = (int)value;
        credits = credits + 3;
        return Ok(credits);
    }

    return NotFound();
}

Then, if you send a request:

POST ~/odata/Courses/AlterCredits
Content-Type: application/json;odata=verbose
Content: {"Credit":9}

You can get a response like this:

{
  "d":{
    "AlterCredits":12
  }
}

For your questions:

  1. IList conventions = ODataRoutingConventions.CreateDefault(); //Do I need this?

    Answer: No, you needn't. Just using the default as:

    config.Routes.MapODataServiceRoute("ODataRoute", "odata", GetModel());

  2. //[ODataRoute("AlterCredits(key={key},credit={credit})")]

    Answer: No, you needn't the ODataRouteAttribute for bind action.

Thanks.