HttpResponseMessage - Decompression of Gzip respone from an API Call throws the following exceptiong - The response ended prematurely

Question

I am actually consuming a REST Service from which I receive the response compressed as Gzip so, following is my code

HttpClientHandler handler = new HttpClientHandler()
{
    AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate
};
var httpClient = new HttpClient(handler);
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var result = await httpClient.GetAsync(url);

I get an exception of the last line "await httpClient.GetAsync(url)"

Following is the stack trace :

at System.Net.Http.HttpConnection.<FillAsync>d__87.MoveNext()
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Net.Http.HttpConnection.ChunkedEncodingReadStream.<CopyToAsyncCore>d__10.MoveNext()
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)   
at System.IO.Compression.DeflateStream.CopyToStream.<CopyFromSourceToDestinationAsync>d__6.MoveNext()
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Net.Http.DecompressionHandler.DecompressedContent.<SerializeToStreamAsync>d__5.MoveNext()
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()  
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Net.Http.HttpContent.<LoadIntoBufferAsyncCore>d__54.MoveNext()

As a quick update: I did try a different implementation of the call as follow :

HttpWebRequest Http = (HttpWebRequest)WebRequest.Create("url");

Http.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip,deflate");
HttpWebResponse WebResponse = (HttpWebResponse)Http.GetResponse();
Stream responseStream = responseStream = WebResponse.GetResponseStream();
if (WebResponse.ContentEncoding.ToLower().Contains("gzip"))
{
    responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
}
StreamReader Reader = new StreamReader(responseStream, Encoding.Default);
string responseAsString= Reader.ReadToEnd();
WebResponse.Close();
responseStream.Close();

I am getting an exception on the following line string responseAsString= Reader.ReadToEnd();

The exception message is also "The response ended prematurely."

Following is the stack trace:

at System.Net.Http.HttpConnection.Fill()
at System.Net.Http.HttpConnection.ChunkedEncodingReadStream.Read(Span`1 buffer)
at System.Net.Http.HttpBaseStream.Read(Byte[] buffer, Int32 offset, Int32 count)
at System.IO.Compression.DeflateStream.ReadCore(Span`1 buffer)
at System.IO.Compression.DeflateStream.Read(Byte[] array, Int32 offset, Int32 count)
at System.IO.StreamReader.ReadBuffer()
at System.IO.StreamReader.ReadToEnd()
at ApiCall.Program.<Main>d__0.MoveNext() in 
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
at ApiCall.Program.<Main>(String[] args)

Answer 1

Try adding HttpCompletionOption.ResponseContentRead to your GetAsync call:

var result = await httpClient.GetAsync(url, HttpCompletionOption.ResponseContentRead);

This should make your code wait until the entire response has been read.