Review for #581 (#651)

Author: sungam3r

src/Transports.AspNetCore/GraphQLHttpMiddleware.cs

@@ -61,9 +61,12 @@ public async Task InvokeAsync(HttpContext context)
             if (!isGet && !isPost)
             {
                 httpResponse.Headers["Allow"] = "GET, POST";
-                await WriteErrorResponseAsync(httpResponse, writer, cancellationToken,
+                await WriteErrorResponseAsync(
+                    httpResponse,
+                    writer,
+                    cancellationToken,
                     $"Invalid HTTP method. Only GET and POST are supported. {DOCS_URL}",
-                    httpStatusCode: HttpStatusCode.MethodNotAllowed
+                    HttpStatusCode.MethodNotAllowed
                 );
                 return;
             }
@@ -75,7 +78,12 @@ await WriteErrorResponseAsync(httpResponse, writer, cancellationToken,
             {
                 if (!MediaTypeHeaderValue.TryParse(httpRequest.ContentType, out var mediaTypeHeader))
                 {
-                    await WriteErrorResponseAsync(httpResponse, writer, cancellationToken, $"Invalid 'Content-Type' header: value '{httpRequest.ContentType}' could not be parsed.");
+                    await WriteErrorResponseAsync(
+                        httpResponse,
+                        writer,
+                        cancellationToken,
+                        $"Invalid 'Content-Type' header: value '{httpRequest.ContentType}' could not be parsed.",
+                        HttpStatusCode.BadRequest);
                     return;
                 }
 
@@ -88,7 +96,7 @@ await WriteErrorResponseAsync(httpResponse, writer, cancellationToken,
                             var message = deserializationResult.Exception is null
                                 ? "JSON body text could not be parsed."
                                 : $"JSON body text could not be parsed. {deserializationResult.Exception.Message}";
-                            await WriteErrorResponseAsync(httpResponse, writer, cancellationToken, message);
+                            await WriteErrorResponseAsync(httpResponse, writer, cancellationToken, message, HttpStatusCode.BadRequest);
                             return;
                         }
                         bodyGQLRequest = deserializationResult.Single;
@@ -132,9 +140,12 @@ await WriteErrorResponseAsync(
 
                 if (string.IsNullOrWhiteSpace(gqlRequest.Query))
                 {
-                    await WriteErrorResponseAsync(httpResponse, writer, cancellationToken,
+                    await WriteErrorResponseAsync(
+                        httpResponse,
+                        writer,
+                        cancellationToken,
                         "GraphQL query is missing.",
-                        httpStatusCode: HttpStatusCode.BadRequest
+                        HttpStatusCode.BadRequest
                     );
                     return;
                 }
@@ -204,7 +215,7 @@ protected virtual Task RequestExecutedAsync(in GraphQLRequestExecutionResult req
         }
 
         private Task WriteErrorResponseAsync(HttpResponse httpResponse, IDocumentWriter writer, CancellationToken cancellationToken,
-            string errorMessage, HttpStatusCode httpStatusCode = HttpStatusCode.BadRequest)
+            string errorMessage, HttpStatusCode httpStatusCode)
         {
             var result = new ExecutionResult
             {

src/Transports.AspNetCore/GraphQLRequestDeserializationException.cs

@@ -2,6 +2,10 @@
 
 namespace GraphQL.Server.Transports.AspNetCore
 {
+    /// <summary>
+    /// Exception used by <see cref="IGraphQLRequestDeserializer"/> implementations
+    /// when deserialization failed.
+    /// </summary>
     public class GraphQLRequestDeserializationException : Exception
     {
         public GraphQLRequestDeserializationException(string message) : base(message)
@@ -12,6 +16,14 @@ public GraphQLRequestDeserializationException(Exception inner) : base(inner.Mess
         {
         }
 
+        public GraphQLRequestDeserializationException(string message, Exception inner) : base(message, inner)
+        {
+        }
+
+        /// <summary>
+        /// Creates an instance of <see cref="GraphQLRequestDeserializationException"/> for a situations
+        /// when the first symbol of JSON body neither '{' nor '['.
+        /// </summary>
         public static GraphQLRequestDeserializationException InvalidFirstChar()
         {
             return new GraphQLRequestDeserializationException("Body text should start with '{' for normal graphql query or with '[' for batched query.");

src/Transports.AspNetCore/GraphQLRequestDeserializationResult.cs

@@ -10,7 +10,7 @@ public class GraphQLRequestDeserializationResult
         /// Flag indicating success. When false, the <see cref="GraphQLHttpMiddleware{TSchema}"/>
         /// will return a 400 BadRequest HTTP status to the client.
         /// </summary>
-        public bool IsSuccessful { get; set; }
+        public bool IsSuccessful { get; set; } // TODO: delete in v6
 
         /// <summary>
         /// A deserialized GraphQL request,
@@ -25,7 +25,7 @@ public class GraphQLRequestDeserializationResult
         public GraphQLRequest[] Batch { get; set; }
 
         /// <summary>
-        /// If deserialization throws an exception, it is stored here
+        /// If deserialization throws an exception, it is stored here.
         /// </summary>
         public GraphQLRequestDeserializationException Exception { get; set; }
     }

tests/ApiApprovalTests/GraphQL.Server.Transports.AspNetCore.approved.txt

@@ -26,6 +26,7 @@ namespace GraphQL.Server.Transports.AspNetCore
     {
         public GraphQLRequestDeserializationException(System.Exception inner) { }
         public GraphQLRequestDeserializationException(string message) { }
+        public GraphQLRequestDeserializationException(string message, System.Exception inner) { }
         public static GraphQL.Server.Transports.AspNetCore.GraphQLRequestDeserializationException InvalidFirstChar() { }
     }
     public class GraphQLRequestDeserializationResult