Fixed: use status code from error; unwrap reflection errors

Author: Bart Koelman

src/Examples/JsonApiDotNetCoreExample/Controllers/ThrowingResourcesController.cs

@@ -0,0 +1,18 @@
+using JsonApiDotNetCore.Configuration;
+using JsonApiDotNetCore.Controllers;
+using JsonApiDotNetCore.Services;
+using JsonApiDotNetCoreExample.Models;
+using Microsoft.Extensions.Logging;
+
+namespace JsonApiDotNetCoreExample.Controllers
+{
+    public sealed class ThrowingResourcesController : JsonApiController<ThrowingResource>
+    {
+        public ThrowingResourcesController(
+            IJsonApiOptions jsonApiOptions,
+            ILoggerFactory loggerFactory,
+            IResourceService<ThrowingResource> resourceService)
+            : base(jsonApiOptions, loggerFactory, resourceService)
+        { }
+    }
+}

src/Examples/JsonApiDotNetCoreExample/Data/AppDbContext.cs

@@ -19,6 +19,7 @@ public sealed class AppDbContext : DbContext
         public DbSet<ArticleTag> ArticleTags { get; set; }
         public DbSet<IdentifiableArticleTag> IdentifiableArticleTags { get; set; }
         public DbSet<Tag> Tags { get; set; }
+        public DbSet<ThrowingResource> ThrowingResources { get; set; }
 
         public AppDbContext(DbContextOptions<AppDbContext> options) : base(options) { }
 

src/Examples/JsonApiDotNetCoreExample/Models/ThrowingResource.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Diagnostics;
+using System.Linq;
+using JsonApiDotNetCore.Formatters;
+using JsonApiDotNetCore.Models;
+
+namespace JsonApiDotNetCoreExample.Models
+{
+    public sealed class ThrowingResource : Identifiable
+    {
+        [Attr]
+        public string FailsOnSerialize
+        {
+            get
+            {
+                var isSerializingResponse = new StackTrace().GetFrames()
+                    .Any(frame => frame.GetMethod().DeclaringType == typeof(JsonApiWriter));
+                
+                if (isSerializingResponse)
+                {
+                    throw new InvalidOperationException($"The value for the '{nameof(FailsOnSerialize)}' property is currently unavailable.");
+                }
+
+                return string.Empty;
+            }
+            set { }
+        }
+    }
+}

src/JsonApiDotNetCore/Formatters/JsonApiWriter.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Net;
 using System.Net.Http;
+using System.Reflection;
 using System.Text;
 using System.Threading.Tasks;
 using JsonApiDotNetCore.Exceptions;
@@ -54,6 +55,8 @@ public async Task WriteAsync(OutputFormatterWriteContext context)
                 {
                     var errorDocument = _exceptionHandler.HandleException(exception);
                     responseContent = _serializer.Serialize(errorDocument);
+
+                    response.StatusCode = (int)errorDocument.GetErrorStatusCode();
                 }
             }
 
@@ -79,6 +82,10 @@ private string SerializeResponse(object contextObject, HttpStatusCode statusCode
             {
                 return _serializer.Serialize(contextObject);
             }
+            catch (TargetInvocationException exception)
+            {
+                throw new InvalidResponseBodyException(exception.InnerException);
+            }
             catch (Exception exception)
             {
                 throw new InvalidResponseBodyException(exception);

src/JsonApiDotNetCore/Serialization/Server/ResponseSerializer.cs

@@ -83,7 +83,7 @@ private string SerializeErrorDocument(ErrorDocument errorDocument)
         /// </remarks>
         internal string SerializeSingle(IIdentifiable entity)
         {
-            if (RequestRelationship != null)
+            if (RequestRelationship != null && entity != null)
                return JsonConvert.SerializeObject(((ResponseResourceObjectBuilder)_resourceObjectBuilder).Build(entity, RequestRelationship));
 
             var (attributes, relationships) = GetFieldsToSerialize();

test/JsonApiDotNetCoreExampleTests/Acceptance/Spec/ThrowingResourceTests.cs

@@ -0,0 +1,46 @@
+using System.Linq;
+using System.Net;
+using System.Threading.Tasks;
+using JsonApiDotNetCore.Models.JsonApiDocuments;
+using JsonApiDotNetCoreExample.Models;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using Xunit;
+
+namespace JsonApiDotNetCoreExampleTests.Acceptance.Spec
+{
+    public class ThrowingResourceTests : FunctionalTestCollection<StandardApplicationFactory>
+    {
+        public ThrowingResourceTests(StandardApplicationFactory factory) : base(factory)
+        {
+        }
+
+        [Fact]
+        public async Task GetThrowingResource_Fails()
+        {
+            // Arrange
+            var throwingResource = new ThrowingResource();
+            _dbContext.Add(throwingResource);
+            _dbContext.SaveChanges();
+
+            // Act
+            var (body, response) = await Get($"/api/v1/throwingResources/{throwingResource.Id}");
+
+            // Assert
+            AssertEqualStatusCode(HttpStatusCode.InternalServerError, response);
+
+            var errorDocument = JsonConvert.DeserializeObject<ErrorDocument>(body);
+
+            Assert.Single(errorDocument.Errors);
+            Assert.Equal(HttpStatusCode.InternalServerError, errorDocument.Errors[0].StatusCode);
+            Assert.Equal("Failed to serialize response body.", errorDocument.Errors[0].Title);
+            Assert.Equal("The value for the 'FailsOnSerialize' property is currently unavailable.", errorDocument.Errors[0].Detail);
+
+            var stackTraceLines =
+                ((JArray) errorDocument.Errors[0].Meta.Data["stackTrace"]).Select(token => token.Value<string>());
+            
+            Assert.Contains(stackTraceLines, line => line.Contains(
+                "System.InvalidOperationException: The value for the 'FailsOnSerialize' property is currently unavailable."));
+        }
+    }
+}