Sockets in C#: How to get the response stream?
I'm trying to replace this:
void ProcessRequest(object listenerContext)
{
var context = (HttpListenerContext)listenerContext;
Uri URL = new Uri(context.Request.RawUrl);
HttpWebRequest.DefaultWebProxy = null;
HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(URL);
httpWebRequest.Method = context.Request.HttpMethod;
httpWebRequest.Headers.Clear();
if (context.Request.UserAgent != null) httpWebRequest.UserAgent = context.Request.UserAgent;
foreach (string headerKey in context.Request.Headers.AllKeys)
{
try { httpWebRequest.Headers.Set(headerKey, context.Request.Headers[headerKey]); }
catch (Exception) { }
}
using (HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse())
{
Stream responseStream = httpWebResponse.GetResponseStream();
if (httpWebResponse.ContentEncoding.ToLower().Contains("gzip"))
responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
else if (httpWebResponse.ContentEncoding.ToLower().Contains("deflate"))
responseStream = new DeflateStream(responseStream, CompressionMode.Decompress);
MemoryStream memStream = new MemoryStream();
byte[] respBuffer = new byte[4096];
try
{
int bytesRead = responseStream.Read(respBuffer, 0, respBuffer.Length);
while (bytesRead > 0)
{
memStream.Write(respBuffer, 0, bytesRead);
bytesRead = responseStream.Read(respBuffer, 0, respBuffer.Length);
}
}
finally
{
responseStream.Close();
}
byte[] msg = memStream.ToArray();
context.Response.ContentLength64 = msg.Length;
using (Stream strOut = context.Response.OutputStream)
{
strOut.Write(msg, 0, msg.Length);
}
}
catch (Exception ex)
{
// Some error handling
}
}
with sockets. This is what I have so far:
void ProcessRequest(object listenerContext)
{
HttpListenerContext context = (HttpListenerContext)listenerContext;
Uri URL = new Uri(context.Request.RawUrl);
string getString = string.Format("GET {0} HTTP/1.1\r\nHost: {1}\r\nAccept-Encoding: gzip\r\n\r\n",
context.Request.Url.PathAndQuery,
context.Request.UserHostName);
Socket socket = null;
string[] hostAndPort;
if (context.Request.UserHostName.Contains(":"))
{
hostAndPort = context.Request.UserHostName.Split(':');
}
else
{
hostAndPort = new string[] { context.Request.UserHostName, "80" };
}
IPHostEntry ipAddress = Dns.GetHostEntry(hostAndPort[0]);
IPEndPoint ip = new IPEndPoint(IPAddress.Parse(ipAddress.AddressList[0].ToString()), int.Parse(hostAndPort[1]));
socket = new Socket(ip.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
socket.Connect(ip);
BEGIN NEW CODE
Encoding ASCII = Encoding.ASCII;
Byte[] byteGetString = ASCII.GetBytes(getString);
Byte[] receiveByte = new Byte[256];
string response = string.Empty;
socket.Send(byteGetString, byteGetString.Length, 0);
Int32 bytes = socket.Receive(receiveByte, receiveByte.Length, 0);
response += ASCII.GetString(receiveByte, 0, bytes);
while (bytes > 0)
{
bytes = socket.Receive(receiveByte, receiveByte.Length, 0);
strPage = strPage + ASCII.GetString(receiveByte, 0, bytes);
}
socket.Close();
string separator = "\r\n\r\n";
string header = strPage.Substring(0,strPage.IndexOf(separator));
string content = strPage.Remove(0, strPage.IndexOf(separator) + 4);
byte[] byteResponse = ASCII.GetBytes(content);
context.Response.ContentLength64 = byteResponse .Length;
context.Response.OutputStream.Write(byteResponse , 0, byteResponse .Length);
context.Response.OutputStream.Close();
END NEW CODE
After connecting to the socket I don't know how to get the Stream response to decompress, and send back to context.Response.OutputStream
Any help will be appreciated. Thanks. Cheers.
EDIT 2: With this edit now seems to be working fine (same as HttpWebRequest at least). Do you find any error here?
EDIT 3: False alarm... Still can't get this working
EDIT 4: I needed to add the following lines to Scott's code ... because not always the first to bytes of reponseStream are the gzip magic number. The sequence seems to be: 0x0a (10), 0x1f (31), 0x8b (139). The last two are the gzip magic number. The first number was always before in my tests.
if (contentEncoding.Equals("gzip"))
{
int magicNumber = 0;
while (magicNumber != 10)
magicNumber = responseStream.ReadByte();
responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
}
Answer
Here's some code that works for me.
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.IO.Compression;
namespace HttpUsingSockets {
public class Program {
private static readonly Encoding DefaultEncoding = Encoding.ASCII;
private static readonly byte[] LineTerminator = new byte[] { 13, 10 };
public static void Main(string[] args) {
var host = "stackoverflow.com";
var url = "/questions/523930/sockets-in-c-how-to-get-the-response-stream";
IPHostEntry ipAddress = Dns.GetHostEntry(host);
var ip = new IPEndPoint(ipAddress.AddressList[0], 80);
using (var socket = new Socket(ip.AddressFamily, SocketType.Stream, ProtocolType.Tcp)) {
socket.Connect(ip);
using (var n = new NetworkStream(socket)) {
SendRequest(n, new[] {"GET " + url + " HTTP/1.1", "Host: " + host, "Connection: Close", "Accept-Encoding: gzip"});
var headers = new Dictionary<string, string>();
while (true) {
var line = ReadLine(n);
if (line.Length == 0) {
break;
}
int index = line.IndexOf(':');
headers.Add(line.Substring(0, index), line.Substring(index + 2));
}
string contentEncoding;
if (headers.TryGetValue("Content-Encoding", out contentEncoding)) {
Stream responseStream = n;
if (contentEncoding.Equals("gzip")) {
responseStream = new GZipStream(responseStream, CompressionMode.Decompress);
}
else if (contentEncoding.Equals("deflate")) {
responseStream = new DeflateStream(responseStream, CompressionMode.Decompress);
}
var memStream = new MemoryStream();
var respBuffer = new byte[4096];
try {
int bytesRead = responseStream.Read(respBuffer, 0, respBuffer.Length);
while (bytesRead > 0) {
memStream.Write(respBuffer, 0, bytesRead);
bytesRead = responseStream.Read(respBuffer, 0, respBuffer.Length);
}
}
finally {
responseStream.Close();
}
var body = DefaultEncoding.GetString(memStream.ToArray());
Console.WriteLine(body);
}
else {
while (true) {
var line = ReadLine(n);
if (line == null) {
break;
}
Console.WriteLine(line);
}
}
}
}
}
static void SendRequest(Stream stream, IEnumerable<string> request) {
foreach (var r in request) {
var data = DefaultEncoding.GetBytes(r);
stream.Write(data, 0, data.Length);
stream.Write(LineTerminator, 0, 2);
}
stream.Write(LineTerminator, 0, 2);
// Eat response
var response = ReadLine(stream);
}
static string ReadLine(Stream stream) {
var lineBuffer = new List<byte>();
while (true) {
int b = stream.ReadByte();
if (b == -1) {
return null;
}
if (b == 10) {
break;
}
if (b != 13) {
lineBuffer.Add((byte)b);
}
}
return DefaultEncoding.GetString(lineBuffer.ToArray());
}
}
}
You could substitute this for the Socket/NetworkStream and save a bit of work.
using (var client = new TcpClient(host, 80)) {
using (var n = client.GetStream()) {
}
}