[SOLVED] ASP.NET web api 2 truncating json response

Issue

I’m experiencing a very weird intermittent issue with my API calls. Sometimes the response gets truncated.

• There isn’t a pattern for how or when it gets truncated.
• Response size is 200kb and configured response limit is 20mb.

Formatters configuration:

private static HttpConfiguration ConfigureFormatters(this HttpConfiguration config)
{
    config.Formatters.Clear();
    config.Formatters.Add(new JsonMediaTypeFormatter());
    config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();

    return config;
}

Simplified Api call:

[HttpGet, Route]
public IHttpActionResult Explore(int cityId)
{
    var lists = exploreBuilderService.Build(cityId);
    return Ok(lists);
}

lists type is List<SomeModel>. SomeModel is DTO with no circular references.

Sample response:

Response Headers
Content-Type: application/json; charset=utf-8
Server: Microsoft-IIS/10.0
X-Powered-By: ASP.NET
Date: Fri, 17 Jan 2020 12:02:37 GMT
Content-Length: 290248

Data
[..., {"id":47

... are other objects in the array.
It looks like json response string is cut in a random place. Our android application fails with MalformedJsonException when the response comes like this. It happens once on like 5-10 requests for the same data set.

Did you encounter a problem like this? Where should I look for potential problems causing this?

Solution

The issue was with one of our middlewares which did response interception.

Answered By – Marko Marinovic

Answer Checked By – Willingham (BugsFixing Volunteer)