Merge pull request #17 from BennieCopeland/empty-body-bug

Catch exception thrown by JsonTextReader when the request body is empty.

src/ThothSerializer.fs

@@ -55,16 +55,21 @@ type ThothSerializer (?caseStrategy : CaseStrategy, ?extra : ExtraCoders, ?skipN
 
     static member ReadBodyRaw (ctx: HttpContext) =
         task {
-            use stream = new System.IO.StreamReader(ctx.Request.Body, Utf8EncodingWithoutBom, true, DefaultBufferSize, true)
-            use jsonReader = new JsonTextReader(stream)
-            let! json = JValue.ReadFromAsync jsonReader
-            return json
+            try
+                use stream = new System.IO.StreamReader(ctx.Request.Body, Utf8EncodingWithoutBom, true, DefaultBufferSize, true)
+                use jsonReader = new JsonTextReader(stream)
+                let! json = JValue.ReadFromAsync jsonReader
+                return Ok json
+            with
+                | :? Newtonsoft.Json.JsonReaderException as ex ->
+                    return Error("Given an invalid JSON: " + ex.Message)
         }
 
     static member ReadBody (ctx: HttpContext) (decoder: Decoder<'T>) =
         task {
-            let! json = ThothSerializer.ReadBodyRaw ctx
-            return Decode.fromValue "$" decoder json
+            match! ThothSerializer.ReadBodyRaw ctx with
+            | Ok json -> return Decode.fromValue "$" decoder json
+            | Error e -> return Error e
         }
 
     static member ReadBodyUnsafe (ctx: HttpContext) (decoder: Decoder<'T>) =

tests/ThothSerializer.fs

@@ -167,4 +167,14 @@ let tests =
 
             Expect.equal content json "Deserialization failure"
         }
+
+        testTask "DeserializationWhenBodyIsEmpty" {
+            let host = createHost ()
+            use _ = host.StartAsync ()
+            let client = new HttpClient()
+            let! (response : HttpResponseMessage) = client.PostAsync("http://localhost:5000/", null)
+            let! content = response.Content.ReadAsStringAsync()
+
+            Expect.stringStarts content "Error while deserializing" "Deserialization exception handling failure"
+        }
   ]