Single controller with multiple GET methods in ASP.NET Web API

Question

In Web API I had a class of similar structure:

public class SomeController : ApiController
{
    [WebGet(UriTemplate = "{itemSource}/Items")]
    public SomeValue GetItems(CustomParam parameter) { ... }

    [WebGet(UriTemplate = "{itemSource}/Items/{parent}")]
    public SomeValue GetChildItems(CustomParam parameter, SomeObject parent) { ... }
}

Since we could map individual methods, it was very simple to get the right request at the right place. For similar class which had only a single GET method but also had an Object parameter, I successfully used IActionValueBinder. However, in the case described above I get the following error:

Multiple actions were found that match the request: 

SomeValue GetItems(CustomParam parameter) on type SomeType

SomeValue GetChildItems(CustomParam parameter, SomeObject parent) on type SomeType

I am trying to approach this problem by overriding the ExecuteAsync method of ApiController but with no luck so far. Any advice on this issue?

Edit: I forgot to mention that now I am trying to move this code on ASP.NET Web API which has a different approach to routing. The question is, how do I make the code work on ASP.NET Web API?

Answer 1

This is the best way I have found to support extra GET methods and support the normal REST methods as well. Add the following routes to your WebApiConfig:

routes.MapHttpRoute("DefaultApiWithId", "Api/{controller}/{id}", new { id = RouteParameter.Optional }, new { id = @"\d+" });
routes.MapHttpRoute("DefaultApiWithAction", "Api/{controller}/{action}");
routes.MapHttpRoute("DefaultApiGet", "Api/{controller}", new { action = "Get" }, new { httpMethod = new HttpMethodConstraint(HttpMethod.Get) });
routes.MapHttpRoute("DefaultApiPost", "Api/{controller}", new {action = "Post"}, new {httpMethod = new HttpMethodConstraint(HttpMethod.Post)});

I verified this solution with the test class below. I was able to successfully hit each method in my controller below:

public class TestController : ApiController
{
    public string Get()
    {
        return string.Empty;
    }

    public string Get(int id)
    {
        return string.Empty;
    }

    public string GetAll()
    {
        return string.Empty;
    }

    public void Post([FromBody]string value)
    {
    }

    public void Put(int id, [FromBody]string value)
    {
    }

    public void Delete(int id)
    {
    }
}

I verified that it supports the following requests:

GET /Test
GET /Test/1
GET /Test/GetAll
POST /Test
PUT /Test/1
DELETE /Test/1

Note That if your extra GET actions do not begin with 'Get' you may want to add an HttpGet attribute to the method.

Answer 2

Go from this:

config.Routes.MapHttpRoute("API Default", "api/{controller}/{id}",
            new { id = RouteParameter.Optional });

To this:

config.Routes.MapHttpRoute("API Default", "api/{controller}/{action}/{id}",
            new { id = RouteParameter.Optional });

Hence, you can now specify which action (method) you want to send your HTTP request to.

posting to "http://localhost:8383/api/Command/PostCreateUser" invokes:

public bool PostCreateUser(CreateUserCommand command)
{
    //* ... *//
    return true;
}

and posting to "http://localhost:8383/api/Command/PostMakeBooking" invokes:

public bool PostMakeBooking(MakeBookingCommand command)
{
    //* ... *//
    return true;
}

I tried this in a self hosted WEB API service application and it works like a charm :)

Answer 3

I find attributes to be cleaner to use than manually adding them via code. Here is a simple example.

[RoutePrefix("api/example")]
public class ExampleController : ApiController
{
    [HttpGet]
    [Route("get1/{param1}")] //   /api/example/get1/1?param2=4
    public IHttpActionResult Get(int param1, int param2)
    {
        Object example = null;
        return Ok(example);
    }

}

You also need this in your webapiconfig

config.Routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

config.Routes.MapHttpRoute(
    name: "ActionApi",
    routeTemplate: "api/{controller}/{action}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

Some Good Links http://www.asp.net/web-api/overview/getting-started-with-aspnet-web-api/tutorial-your-first-web-api This one explains routing better. http://www.asp.net/web-api/overview/web-api-routing-and-actions/routing-in-aspnet-web-api

Answer 4

You need to define further routes in global.asax.cs like this:

routes.MapHttpRoute(
    name: "Api with action",
    routeTemplate: "api/{controller}/{action}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

Answer 5

With the newer Web Api 2 it has become easier to have multiple get methods.

If the parameter passed to the GET methods are different enough for the attribute routing system to distinguish their types as is the case with ints and Guids you can specify the expected type in the [Route...] attribute

For example -

[RoutePrefix("api/values")]
public class ValuesController : ApiController
{

    // GET api/values/7
    [Route("{id:int}")]
    public string Get(int id)
    {
       return $"You entered an int - {id}";
    }

    // GET api/values/AAC1FB7B-978B-4C39-A90D-271A031BFE5D
    [Route("{id:Guid}")]
    public string Get(Guid id)
    {
       return $"You entered a GUID - {id}";
    }
} 

For more details about this approach, see here http://nodogmablog.bryanhogan.net/2017/02/web-api-2-controller-with-multiple-get-methods-part-2/

Another options is to give the GET methods different routes.

    [RoutePrefix("api/values")]
    public class ValuesController : ApiController
    {
        public string Get()
        {
            return "simple get";
        }

        [Route("geta")]
        public string GetA()
        {
            return "A";
        }

        [Route("getb")]
        public string GetB()
        {
            return "B";
        }
   }

See here for more details - http://nodogmablog.bryanhogan.net/2016/10/web-api-2-controller-with-multiple-get-methods/

Answer 6

In ASP.NET Core 2.0 you can add Route attribute to the controller:

[Route("api/[controller]/[action]")]
public class SomeController : Controller
{
    public SomeValue GetItems(CustomParam parameter) { ... }

    public SomeValue GetChildItems(CustomParam parameter, SomeObject parent) { ... }
}

Answer 7

In VS 2019, this works with ease:

[Route("api/[controller]/[action]")] //above the controller class

And in the code:

[HttpGet]
[ActionName("GetSample1")]
public Ilist<Sample1> GetSample1()
{
    return getSample1();
}
[HttpGet]
[ActionName("GetSample2")]
public Ilist<Sample2> GetSample2()
{
    return getSample2();
}
[HttpGet]
[ActionName("GetSample3")]
public Ilist<Sample3> GetSample3()
{
    return getSample3();
}
[HttpGet]
[ActionName("GetSample4")]
public Ilist<Sample4> GetSample4()
{
    return getSample4();
}

You can have multiple gets like above mentioned.

Answer 8

I was trying to use Web Api 2 attribute routing to allow for multiple Get methods, and I had incorporated the helpful suggestions from previous answers, but in the Controller I had only decorated the "special" method (example):

[Route( "special/{id}" )]
public IHttpActionResult GetSomethingSpecial( string id ) {

...without also also placing a [RoutePrefix] at the top of the Controller:

[RoutePrefix("api/values")]
public class ValuesController : ApiController

I was getting errors stating that no Route was found matching the submitted URI. Once I had both the [Route] decorating the method as well as [RoutePrefix] decorating the Controller as a whole, it worked.

Answer 9

I am not sure if u have found the answer, but I did this and it works

public IEnumerable<string> Get()
{
    return new string[] { "value1", "value2" };
}

// GET /api/values/5
public string Get(int id)
{
    return "value";
}

// GET /api/values/5
[HttpGet]
public string GetByFamily()
{
    return "Family value";
}

Now in global.asx

routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

routes.MapHttpRoute(
    name: "DefaultApi2",
    routeTemplate: "api/{controller}/{action}",
    defaults: new { id = RouteParameter.Optional }
);

routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

routes.MapRoute(
    name: "Default",
    url: "{controller}/{action}/{id}",
    defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);

Answer 10

Have you tried switching over to WebInvokeAttribute and setting the Method to "GET"?

I believe I had a similar problem and switched to explicitly telling which Method (GET/PUT/POST/DELETE) is expected on most, if not all, my methods.

public class SomeController : ApiController
{
    [WebInvoke(UriTemplate = "{itemSource}/Items"), Method="GET"]
    public SomeValue GetItems(CustomParam parameter) { ... }

    [WebInvoke(UriTemplate = "{itemSource}/Items/{parent}", Method = "GET")]
    public SomeValue GetChildItems(CustomParam parameter, SomeObject parent) { ... }
}

The WebGet should handle it but I've seen it have some issues with multiple Get much less multiple Get of the same return type.

[Edit: none of this is valid with the sunset of WCF WebAPI and the migration to ASP.Net WebAPI on the MVC stack]

Answer 11

**Add Route function to direct the routine what you want**
    public class SomeController : ApiController
    {
        [HttpGet()]
        [Route("GetItems")]
        public SomeValue GetItems(CustomParam parameter) { ... }

        [HttpGet()]
        [Route("GetChildItems")]
        public SomeValue GetChildItems(CustomParam parameter, SomeObject parent) { ... }
    }

Answer 12

The lazy/hurry alternative (Dotnet Core 2.2):

[HttpGet("method1-{item}")]
public string Method1(var item) { 
return "hello" + item;}

[HttpGet("method2-{item}")]
public string Method2(var item) { 
return "world" + item;}

Calling them :

localhost:5000/api/controllername/method1-42

"hello42"

localhost:5000/api/controllername/method2-99

"world99"

Answer 13

By default [Route("api/[controller]") will generated by .Net Core/Asp.Net Web API.You need to modify little bit,just add [Action] like [Route("api/[controller]/[action]")]. I have mentioned a dummy solution:

// Default generated controller
//
[Route("api/[controller]")
public class myApiController : Controller
{
    [HttpGet]
    public string GetInfo()
    {
        return "Information";
    }
}

//
//A little change would do the magic
//

[Route("api/[controller]/[action]")]
public class ServicesController : Controller
{
    [HttpGet]
    [ActionName("Get01")]
    public string Get01()
    {
        return "GET 1";
    }

    [HttpGet]
    [ActionName("Get02")]
    public string Get02()
    {
        return "Get 2";
    }
    
    [HttpPost]
    [ActionName("Post01")]
    public HttpResponseMessage Post01(MyCustomModel01 model)
    {
        if (!ModelState.IsValid)
            return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState);
        
        //.. DO Something ..
        return Request.CreateResonse(HttpStatusCode.OK, "Optional Message");
    }
    
    [HttpPost]
    [ActionName("Post02")]
    public HttpResponseMessage Post02(MyCustomModel02 model)
    {
        if (!ModelState.IsValid)
            return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState);
        
        //.. DO Something ..
        return Request.CreateResonse(HttpStatusCode.OK, "Optional Message");
    }


}

Answer 14

None of the above examples worked for my personal needs. The below is what I ended up doing.

 public class ContainsConstraint : IHttpRouteConstraint
{       
    public string[] array { get; set; }
    public bool match { get; set; }

    /// <summary>
    /// Check if param contains any of values listed in array.
    /// </summary>
    /// <param name="param">The param to test.</param>
    /// <param name="array">The items to compare against.</param>
    /// <param name="match">Whether we are matching or NOT matching.</param>
    public ContainsConstraint(string[] array, bool match)
    {

        this.array = array;
        this.match = match;
    }

    public bool Match(System.Net.Http.HttpRequestMessage request, IHttpRoute route, string parameterName, IDictionary<string, object> values, HttpRouteDirection routeDirection)
    {
        if (values == null) // shouldn't ever hit this.                   
            return true;

        if (!values.ContainsKey(parameterName)) // make sure the parameter is there.
            return true;

        if (string.IsNullOrEmpty(values[parameterName].ToString())) // if the param key is empty in this case "action" add the method so it doesn't hit other methods like "GetStatus"
            values[parameterName] = request.Method.ToString();

        bool contains = array.Contains(values[parameterName]); // this is an extension but all we are doing here is check if string array contains value you can create exten like this or use LINQ or whatever u like.

        if (contains == match) // checking if we want it to match or we don't want it to match
            return true;
        return false;             

    }

To use the above in your route use:

config.Routes.MapHttpRoute("Default", "{controller}/{action}/{id}", new { action = RouteParameter.Optional, id = RouteParameter.Optional}, new { action = new ContainsConstraint( new string[] { "GET", "PUT", "DELETE", "POST" }, true) });

What happens is the constraint kind of fakes in the method so that this route will only match the default GET, POST, PUT and DELETE methods. The "true" there says we want to check for a match of the items in array. If it were false you'd be saying exclude those in the strYou can then use routes above this default method like:

config.Routes.MapHttpRoute("GetStatus", "{controller}/status/{status}", new { action = "GetStatus" });

In the above it is essentially looking for the following URL => http://www.domain.com/Account/Status/Active or something like that.

Beyond the above I'm not sure I'd get too crazy. At the end of the day it should be per resource. But I do see a need to map friendly urls for various reasons. I'm feeling pretty certain as Web Api evolves there will be some sort of provision. If time I'll build a more permanent solution and post.

Answer 15

Couldn't make any of the above routing solutions work -- some of the syntax seems to have changed and I'm still new to MVC -- in a pinch though I put together this really awful (and simple) hack which will get me by for now -- note, this replaces the "public MyObject GetMyObjects(long id)" method -- we change "id"'s type to a string, and change the return type to object.

// GET api/MyObjects/5
// GET api/MyObjects/function
public object GetMyObjects(string id)
{
    id = (id ?? "").Trim();

    // Check to see if "id" is equal to a "command" we support
    // and return alternate data.

    if (string.Equals(id, "count", StringComparison.OrdinalIgnoreCase))
    {
        return db.MyObjects.LongCount();
    }

    // We now return you back to your regularly scheduled
    // web service handler (more or less)

    var myObject = db.MyObjects.Find(long.Parse(id));
    if (myObject == null)
    {
        throw new HttpResponseException
        (
            Request.CreateResponse(HttpStatusCode.NotFound)
        );
    }

    return myObject;
}

Answer 16

If you have multiple Action within same file then pass the same argument e.g. Id to all Action. This is because action only can identify Id, So instead of giving any name to argument only declare Id like this.

---

[httpget]
[ActionName("firstAction")] firstAction(string Id)
{.....
.....
}
[httpget]
[ActionName("secondAction")] secondAction(Int Id)
{.....
.....
}
//Now go to webroute.config file under App-start folder and add following
routes.MapHttpRoute(
name: "firstAction",
routeTemplate: "api/{controller}/{action}/{id}",
defaults: new { id = RouteParameter.Optional }
);

routes.MapHttpRoute(
name: "secondAction",
routeTemplate: "api/{controller}/{action}/{id}",
defaults: new { id = RouteParameter.Optional }
);

Answer 17

Simple Alternative

Just use a query string.

Routing

config.Routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);

Controller

public class TestController : ApiController
{
    public IEnumerable<SomeViewModel> Get()
    {
    }

    public SomeViewModel GetById(int objectId)
    {
    }
}

Requests

GET /Test
GET /Test?objectId=1

Note

Keep in mind that the query string param should not be "id" or whatever the parameter is in the configured route.

Answer 18

Specifying the base path in the [Route] attribute and then adding to the base path in the [HttpGet] worked for me. You can try:

    [Route("api/TestApi")]      //this will be the base path
    public class TestController : ApiController
    {
        [HttpGet]  //example call: 'api/TestApi'
        public string Get()
        {
            return string.Empty;
        }
    
        [HttpGet("{id}")]  //example call: 'api/TestApi/4'
        public string GetById(int id) //method name won't matter
        {
            return string.Empty;
        }
    
        //....

Took me a while to figure since I didn't want to use [Route] multiple times.

Answer 19

Modify the WebApiConfig and add at the end another Routes.MapHttpRoute like this:

config.Routes.MapHttpRoute(
                name: "ServiceApi",
                routeTemplate: "api/Service/{action}/{id}",
                defaults: new { id = RouteParameter.Optional }
            );

Then create a controller like this:

public class ServiceController : ApiController
{
        [HttpGet]
        public string Get(int id)
        {
            return "object of id id";
        }
        [HttpGet]
        public IQueryable<DropDownModel> DropDowEmpresa()
        {
            return db.Empresa.Where(x => x.Activo == true).Select(y =>
                  new DropDownModel
                  {
                      Id = y.Id,
                      Value = y.Nombre,
                  });
        }

        [HttpGet]
        public IQueryable<DropDownModel> DropDowTipoContacto()
        {
            return db.TipoContacto.Select(y =>
                  new DropDownModel
                  {
                      Id = y.Id,
                      Value = y.Nombre,
                  });
        }

        [HttpGet]
        public string FindProductsByName()
        {
            return "FindProductsByName";
        }
}

This is how I solved it. I hope it will help someone.