I'm attempting to request some information using the Stack Exchange API. Supposedly, it returns responses compress with GZip. Using Microsoft's System.IO.Compression.GZipStream or Ionic.Zlib.GZipStream, I'm always told the data is not in GZip format... Even though the response's Content-Encoding is "gzip".
I've also written the bytes from the response to a file and transferred it to a Linux box and attempted to gunzip it, but that also returned an error.
What am I doing wrong? I am sending Accept-Encoding: gzip and getting Content-Encoding: gzip...
System.IO.InvalidDataException - The magic number in GZip header is not correct. Make sure you are passing in a GZip stream.
Here's is runnable code:
internal static readonly string TagSearchUrl = "http://api.stackexchange.com/2.1/tags?site=stackoverflow&inname=c#";
internal static string FetchURL(string url) {
var req = HttpWebRequest.Create(url);
req.Headers["Accept-Encoding"] = "gzip";
var resp = req.GetResponse();
var contentType = resp.Headers["Content-Encoding"];
var responseString = new StreamReader(resp.GetResponseStream()).ReadToEnd();
return UnZip(responseString);
}
public static string UnZip(string value) {
byte[] byteArray = StringToByteArray(value);
using (var ms = new System.IO.MemoryStream(byteArray)) {
//using (var sr = new Ionic.Zlib.GZipStream(ms, Ionic.Zlib.CompressionMode.Decompress)) {
using (var sr = new System.IO.Compression.GZipStream(ms, System.IO.Compression.CompressionMode.Decompress)) {
byteArray = new byte[byteArray.Length];
try {
var count = sr.Read(byteArray, 0, byteArray.Length);
}
finally {
sr.Close();
ms.Close();
}
}
}
return ByteArrayToString(byteArray);
}
private static string ByteArrayToString(byte[] byteArray) {
return System.Text.Encoding.UTF8.GetString(byteArray);
}
private static byte[] StringToByteArray(string value) {
return System.Text.Encoding.UTF8.GetBytes(value);
}