f# - ASP.NET WebAPI unable to post -

i unable post data asp.net webapi server.

i can data webapi server. however, unable post.

the following code fails post:

response = await client.postasync("api/cars", content); 

error:

statuscode: 415, reasonphrase: 'unsupported media type', version: 1.1

client:

[testclass] public class unittest1 {     // http://www.asp.net/web-api/overview/advanced/calling-a-web-api-from-a-net-client     [testmethod]     public async task testmethod1()     {         using (var client = new httpclient())         {             client.baseaddress = new uri("http://localhost:48213/");             client.defaultrequestheaders.accept.clear();             client.defaultrequestheaders.accept.add(new mediatypewithqualityheadervalue("application/json"));              // http             var response = await client.getasync("api/cars");             if (response.issuccessstatuscode)             {                 var result = await response.content.readasstringasync();             }              // http post             using (var content = new stringcontent(@"some_value"))             {                 client.defaultrequestheaders.accept.add(new mediatypewithqualityheadervalue("application/json"));                 response = await client.postasync("api/cars", content);                  if (response.issuccessstatuscode)                 {                     debug.writeline("post successful.");                 }             }         } 

webapi:

namespace fsharpwebapi.controllers  open system.web.http open fsharpwebapi.models  type carscontroller() =     inherit apicontroller()      let values = [| { make = "ford"; model = "mustang" }; { make = "nissan"; model = "titan" } |]      member x.get() = values      member x.post(data) =          ignore 

what updates need make make simple post?

as @fyodor soikin has pointed out, post method generic ('a -> 'b -> unit), , asp.net web api refuses wire such methods.

asp.net web api uses convention on configuration in order figure out how route , handle incoming requests. if http post arrives, it'll go hunting method (partially) named post, , attempt call it. while argue if generic method handle input, it'd possible web api still call it, doesn't that.

you'll need add type annotation - example:

member x.post(data : car) =      ignore 

that's still not going enough, because type of version of post car -> 'a -> unit, return value generic function. i'd surprised if web api knows that.

the reason ignore function, , since post doesn't invoke function, return value function itself.

if want ignore input , return unit, can this:

member x.post(data : car) = () 

this version has type car -> unit, expect web api find acceptable.