Question

I have two HttpPost methods in my api controller and when i am hitting my api i am getting 500 internal server error.

But surprisingly when i remove one of the HttpPost methods i am able to successfully hit my api and retrieve the info i want.

Any idea what might be the problem?

these are the two methods

    [HttpPost]
    [ActionName("PostUser")]
    public HttpResponseMessage PostUser([FromBody]string id)
    {
        var accessToken = id;
        var client = new FacebookClient(accessToken);
        dynamic result = client.Get("me", new { fields = "name,email" });
        string name = result.name;
        string email = result.email;


        var existingUser = this.Repository.FindByUserIdentity(name);

        if (existingUser == null)
        {
            var newUser = new User
            {
                Username = name,
                Email = email,

            };

            var success = this.Repository.CreateAccount(newUser);

            if (!success)
            {
                return Request.CreateResponse(HttpStatusCode.InternalServerError);
            }

            //return created status code as we created the user
            return Request.CreateResponse<User>(HttpStatusCode.Created, newUser);
        }

        return Request.CreateResponse(HttpStatusCode.OK);

    }

    [HttpPost]
    [ActionName("PostEmail")]
    public HttpResponseMessage PostEmail([FromBody]string id)
    {
        var accessToken = id;
        var client = new FacebookClient(accessToken);
        dynamic result = client.Get("me", new { fields = "email" });
        string name = result.name;
        string email = result.email;


        var existingUser = this.Repository.FindByUserIdentity(name);

        if (existingUser == null)
        {
            var newUser = new User
            {                   
                Email = email

            };

            var success = this.Repository.CreateAccount(newUser);

            if (!success)
            {
                return Request.CreateResponse(HttpStatusCode.InternalServerError);
            }

            //return created status code as we created the user
            return Request.CreateResponse<User>(HttpStatusCode.Created, newUser);
        }

        return Request.CreateResponse(HttpStatusCode.OK);

    }

EDIT:

public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

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

Answer 1

It is becuase you have two Post methods in your controller and by covention WebApi only allow one Post method.

To configure two or multiple Post methods you have to configure your route settings.

For detail have a look at the following answer

Multiple HttpPost method in MVC4 Web API Controller