ASP.NET MVC 4 WebAPI (beta) - how to change maximum response buffer size

Question

In ASP.NET MVC 4.0 WebAPI (beta version), I am returning an object that is serialised to JSON that is larger than 65kb. As you can see from the stack trace below, the framework is throwing an exception because this exceeds some internal limit.

System.Net.Http.HttpRequestException: Cannot write more bytes to the buffer than the configured maximum buffer size: 65536.
   at System.Net.Http.HttpContent.LimitMemoryStream.CheckSize(Int32 countToAdd)
   at System.Net.Http.HttpContent.LimitMemoryStream.Write(Byte[] buffer, Int32 offset, Int32 count)
   at System.IO.StreamWriter.Flush(Boolean flushStream, Boolean flushEncoder)
   at System.IO.StreamWriter.Write(Char value)
   at Newtonsoft.Json.JsonWriter.AutoComplete(JsonToken tokenBeingWritten) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\JsonWriter.cs:line 634
   at Newtonsoft.Json.JsonTextWriter.WritePropertyName(String name) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\JsonTextWriter.cs:line 204
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty(JsonWriter writer, Object memberValue, JsonProperty property, JsonContract contract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 209
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 336
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty(JsonWriter writer, Object memberValue, JsonProperty property, JsonContract contract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 209
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 336
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList(JsonWriter writer, IWrappedCollection values, JsonArrayContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 445
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty(JsonWriter writer, Object memberValue, JsonProperty property, JsonContract contract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 209
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 336
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty(JsonWriter writer, Object memberValue, JsonProperty property, JsonContract contract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 209
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 336
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList(JsonWriter writer, IWrappedCollection values, JsonArrayContract contract, JsonProperty member, JsonContract collectionValueContract) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 445
   at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize(JsonWriter jsonWriter, Object value) in d:\Development\Releases\Json\Working\Src\Newtonsoft.Json\Serialization\JsonSerializerInternalWriter.cs:line 59
   at xxx.Api.JsonNetFormatter.<>c__DisplayClass5.<OnWriteToStreamAsync>b__4() in c:\xxx\xxx\xxx.Api\JsonNetFormatter.cs:line 79
   at System.Threading.Tasks.Task.Execute()

I can't find any way to change this default. Can anyone help?

thanks

Answer 1

According to the System.Net.Http.dll released with the nightly source code builds, value of the max buffer size is defined in HttpContent as :

internal const long MaxBufferSize = 0x7fffffffL; // 2147483647

So if you switch to the new version (rather than the beta installer) the problem should go away.

I suggest to switch anyway regardless of this problem as there are quite a few breaking changes and whatever you are building now is guaranteed not to work with the final release.