How to disable Chunked Transfer Encoding in ASP.Net C# using HttpClient

dontbesorry80 picture dontbesorry80 · Feb 17, 2016 · Viewed 8.4k times · Source

I'm trying to post some JSON to an external API which keeps failing because my content is chunked. Please can someone tell me how to disable it?

I'm using ASP.NET 5 so think I'm using System.Net.Http, Version=4.0.1.0

Here is the code I've tried:

using (var client = new HttpClient())
{
    // TODO - Send HTTP requests
    client.BaseAddress = new Uri(apiBaseUrl);
    client.DefaultRequestHeaders.Accept.Clear();
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("SAML", samlToken);
    client.DefaultRequestHeaders.TransferEncodingChunked = false;

    HttpResponseMessage response = await client.PostAsJsonAsync(path, jsonObject);
}

But It still seems to have the Transfer-Encoding set to "chunked" when I check Fiddler.

Can anyone help with this?

Answer

Kevin Smith picture Kevin Smith · Jun 26, 2018

It looks like you need to set the Content-Length header too, if you don't it seems to use the MaxRequestContentBufferSize on HttpClientHandler to chunk the data when sending it.

Try using a StringContent, ByteArrayContent or StreamContent (If the steam is seekable) as these will be able to calculate the length for you.

var content = new StringContent(json);

HttpResponseMessage response = await client.PostAsync(content);

The PostAsJsonAsync extension methods create ObjectContent under the hood which doesn't calculate the Content-Length and return false:

public class ObjectContent : HttpContent
{
    /* snip */

    protected override bool TryComputeLength(out long length)
    {
        length = -1L;
        return false;
    }
}

Thus will always fall back to chunking to the buffer size.