Various small fixes

Author: Bart Koelman

src/Examples/JsonApiDotNetCoreExample/Services/CustomArticleService.cs

@@ -26,12 +26,7 @@ public CustomArticleService(
         public override async Task<Article> GetAsync(int id)
         {
             var newEntity = await base.GetAsync(id);
-
-            if (newEntity != null)
-            {
-                newEntity.Name = "None for you Glen Coco";
-            }
-
+            newEntity.Name = "None for you Glen Coco";
             return newEntity;
         }
     }

src/JsonApiDotNetCore/Exceptions/InvalidRequestBodyException.cs

@@ -9,32 +9,44 @@ namespace JsonApiDotNetCore.Exceptions
     /// </summary>
     public sealed class InvalidRequestBodyException : JsonApiException
     {
+        private readonly string _details;
+        private string _requestBody;
+
         public InvalidRequestBodyException(string reason, string details, string requestBody, Exception innerException = null)
             : base(new Error(HttpStatusCode.UnprocessableEntity)
             {
                 Title = reason != null
                     ? "Failed to deserialize request body: " + reason
                     : "Failed to deserialize request body.",
-                Detail = FormatDetails(details, requestBody, innerException)
             }, innerException)
         {
+            _details = details;
+            _requestBody = requestBody;
+
+            UpdateErrorDetail();
         }
 
-        private static string FormatDetails(string details, string requestBody, Exception innerException)
+        private void UpdateErrorDetail()
         {
-            string text = details ?? innerException?.Message;
+            string text = _details ?? InnerException?.Message;
 
-            if (requestBody != null)
+            if (_requestBody != null)
             {
                 if (text != null)
                 {
                     text += " - ";
                 }
 
-                text += "Request body: <<" + requestBody + ">>";
+                text += "Request body: <<" + _requestBody + ">>";
             }
 
-            return text;
+            Error.Detail = text;
+        }
+
+        public void SetRequestBody(string requestBody)
+        {
+            _requestBody = requestBody;
+            UpdateErrorDetail();
         }
     }
 }

src/JsonApiDotNetCore/Formatters/JsonApiReader.cs

@@ -45,8 +45,9 @@ public async Task<InputFormatterResult> ReadAsync(InputFormatterContext context)
             {
                 model = _deserializer.Deserialize(body);
             }
-            catch (InvalidRequestBodyException)
+            catch (InvalidRequestBodyException exception)
             {
+                exception.SetRequestBody(body);
                 throw;
             }
             catch (Exception exception)

src/JsonApiDotNetCore/Services/DefaultResourceService.cs

@@ -236,7 +236,7 @@ public virtual async Task UpdateRelationshipsAsync(TId id, string relationshipNa
 
         protected virtual async Task<IEnumerable<TResource>> ApplyPageQueryAsync(IQueryable<TResource> entities)
         {
-            if (_pageService.PageSize <= 0)
+            if (_pageService.PageSize == 0)
             {
                 _logger.LogDebug("Fetching complete result set.");
 

test/JsonApiDotNetCoreExampleTests/Acceptance/Spec/CreatingDataTests.cs

@@ -266,6 +266,7 @@ public async Task CreateResource_UnknownEntityType_Fails()
             Assert.Equal(HttpStatusCode.UnprocessableEntity, errorDocument.Errors[0].StatusCode);
             Assert.Equal("Failed to deserialize request body: Payload includes unknown resource type.", errorDocument.Errors[0].Title);
             Assert.StartsWith("The resource 'something' is not registered on the resource graph.", errorDocument.Errors[0].Detail);
+            Assert.Contains("Request body: <<", errorDocument.Errors[0].Detail);
         }
 
         [Fact]