Include request body in logged exception when available

Author: Bart Koelman

src/JsonApiDotNetCore/Exceptions/InvalidRequestBodyException.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Net;
+using System.Text;
 using JsonApiDotNetCore.Models.JsonApiDocuments;
 
 namespace JsonApiDotNetCore.Exceptions
@@ -9,30 +10,32 @@ namespace JsonApiDotNetCore.Exceptions
     /// </summary>
     public sealed class InvalidRequestBodyException : JsonApiException
     {
-        public InvalidRequestBodyException(string reason)
-            : this(reason, null, null)
-        {
-        }
-
-        public InvalidRequestBodyException(string reason, string details)
-            : this(reason, details, null)
-        {
-        }
-
-        public InvalidRequestBodyException(Exception innerException)
-            : this(null, null, innerException)
-        {
-        }
-
-        private InvalidRequestBodyException(string reason, string details = null, Exception innerException = null)
+        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 = details ?? innerException?.Message
+                Detail = FormatDetails(details, requestBody, innerException)
             }, innerException)
         {
         }
+
+        private static string FormatDetails(string details, string requestBody, Exception innerException)
+        {
+            string text = details ?? innerException?.Message;
+
+            if (requestBody != null)
+            {
+                if (text != null)
+                {
+                    text += Environment.NewLine;
+                }
+
+                text += "Request body: <<" + requestBody + ">>";
+            }
+
+            return text;
+        }
     }
 }

src/JsonApiDotNetCore/Formatters/JsonApiReader.cs

@@ -50,15 +50,15 @@ public async Task<InputFormatterResult> ReadAsync(InputFormatterContext context)
             }
             catch (Exception exception)
             {
-                throw new InvalidRequestBodyException(exception);
+                throw new InvalidRequestBodyException(null, null, body, exception);
             }
 
             if (context.HttpContext.Request.Method == "PATCH")
             {
                 var hasMissingId = model is IList list ? CheckForId(list) : CheckForId(model);
                 if (hasMissingId)
                 {
-                    throw new InvalidRequestBodyException("Payload must include id attribute.");
+                    throw new InvalidRequestBodyException("Payload must include id attribute.", null, body);
                 }
             }
 

src/JsonApiDotNetCore/Serialization/Common/BaseDocumentParser.cs

@@ -138,7 +138,7 @@ private IIdentifiable ParseResourceObject(ResourceObject data)
                 throw new InvalidRequestBodyException("Payload includes unknown resource type.",
                     $"The resource '{data.Type}' is not registered on the resource graph. " +
                     "If you are using Entity Framework, make sure the DbSet matches the expected resource name. " +
-                    "If you have manually registered the resource, check that the call to AddResource correctly sets the public name.");
+                    "If you have manually registered the resource, check that the call to AddResource correctly sets the public name.", null);
             }
 
             var entity = resourceContext.ResourceType.New<IIdentifiable>();

test/JsonApiDotNetCoreExampleTests/Acceptance/Spec/UpdatingDataTests.cs

@@ -88,7 +88,7 @@ public async Task Response422IfUpdatingNotSettableAttribute()
             var error = document.Errors.Single();
             Assert.Equal(HttpStatusCode.UnprocessableEntity, error.StatusCode);
             Assert.Equal("Failed to deserialize request body.", error.Title);
-            Assert.Equal("Property set method not found.", error.Detail);
+            Assert.StartsWith("Property set method not found." + Environment.NewLine + "Request body: <<", error.Detail);
         }
 
         [Fact]
@@ -145,7 +145,7 @@ public async Task Respond_422_If_IdNotInAttributeList()
             var error = document.Errors.Single();
             Assert.Equal(HttpStatusCode.UnprocessableEntity, error.StatusCode);
             Assert.Equal("Failed to deserialize request body: Payload must include id attribute.", error.Title);
-            Assert.Null(error.Detail);
+            Assert.StartsWith("Request body: <<", error.Detail);
         }
 
         [Fact]