private void SendRequest()
{
// Record when we first started the download
headerLength = 0;
startTime = DateTime.Now;
// Create a HTTP request using the Deusty.Net.HTTP.HTTPHeader class.
// The HTTP protocol is fairly straightforward, but this class helps hide protocol
// specific information that we're not really concerned with for this AsyncSocket sameple.
HTTPHeader request = HTTPHeader.CreateRequest("GET", FETCH_REQUEST);
request.SetHeaderFieldValue("Host", FETCH_HOST);
String requestStr = request.ToString();
LogInfo("Sending Request:");
LogMessage(requestStr);
// Convert HTTPHeader object to a byte array.
byte[] requestData = Encoding.UTF8.GetBytes(requestStr);
Console.WriteLine(Data.ToHexString(requestData));
// Now write the data over the socket.
// This call is asynchronous, and returns immediately.
// When finished writing, the asyncSocket_DidWrite method is called.
asyncSocket.Write(requestData, WRITE_TIMEOUT, HTTP_HEADERS);
// Setup http response
response = HTTPHeader.CreateEmptyResponse();
// And start reading in the response
asyncSocket.Read(AsyncSocket.CRLFData, READ_HEADER_TIMEOUT, HTTP_HEADERS);
// Reset progress bar
progressBar.Value = 0;
}
private void asyncSocket_DidRead(AsyncSocket sender, byte[] data, long tag)
{
// LogInfo("DidRead: {0}", tag);
if (tag == HTTP_HEADERS)
{
// We read in one line of the http header response
// Do we have the full http header yet?
headerLength += data.Length;
response.AppendBytes(data);
if (!response.IsHeaderComplete())
{
// We don't have a complete header yet
asyncSocket.Read(AsyncSocket.CRLFData, READ_HEADER_TIMEOUT, HTTP_HEADERS);
}
else
{
LogInfo("Received Response: ({0} bytes)", headerLength);
LogMessage(response.ToString());
// Check the http status code
if (response.GetStatusCode() != 200)
{
// We only support status code 200 in this overly simple http client
LogError("HTTP status code is not \"200 OK\"");
LogError("Disconnecting...");
asyncSocket.Close();
return;
}
// Extract the Content-Length
String contentLength = response.GetHeaderFieldValue("Content-Length");
Int32.TryParse(contentLength, out fileSizeInBytes);
// Extract Transfer-Encoding
String transferEncoding = response.GetHeaderFieldValue("Transfer-Encoding");
bool usingChunkedTransfer = String.Equals(transferEncoding, "chunked", StringComparison.OrdinalIgnoreCase);
if (fileSizeInBytes > 0)
{
// Using traditional transfer
totalBytesReceived = 0;
asyncSocket.Read(fileSizeInBytes, READ_BODY_TIMEOUT, HTTP_BODY);
}
else if (usingChunkedTransfer)
{
// Using chunked transfer
// For more information on chunked transfer, see the "HTTP Made Really Easy" website:
// http://www.jmarshall.com/easy/http/
LogInfo("Using chunked transfer - Unable to use progress bar");
chunkedTransferStage = CHUNKED_STAGE_SIZE;
asyncSocket.Read(AsyncSocket.CRLFData, READ_CHUNKSIZE_TIMEOUT, HTTP_BODY_CHUNKED);
}
else
{
LogError("Unable to extract content length, and not using chunked transfer encoding!");
LogError("Disconnecting...");
asyncSocket.Close();
return;
}
}
}
else if (tag == HTTP_BODY)
{
// Write the data to log
try
{
LogMessage(Encoding.UTF8.GetString(data));
}
catch
{
LogError("Cannot convert chunk to UTF-8 string");
}
LogInfo("\r\nDownload complete");
progressBar.Value = 100;
TimeSpan ellapsed = DateTime.Now - startTime;
LogInfo("\r\nTotal Time = {0:N} milliseconds", ellapsed.TotalMilliseconds);
LogInfo("Disconnecting...");
asyncSocket.Close();
}
else if (tag == HTTP_BODY_CHUNKED)
{
if (chunkedTransferStage == CHUNKED_STAGE_SIZE)
{
// We have just read in a line with the size of the chunk data, in hex,
// possibly followed by a semicolon and extra parameters that can be ignored,
// and ending with CRLF
String sizeLine = Encoding.UTF8.GetString(data);
Int32 chunkSizeInBytes;
Int32.TryParse(sizeLine, System.Globalization.NumberStyles.HexNumber, null, out chunkSizeInBytes);
if (chunkSizeInBytes > 0)
{
// Don't forget about the trailing CRLF when downloading the data
chunkSizeInBytes += 2;
chunkedTransferStage = CHUNKED_STAGE_DATA;
asyncSocket.Read(chunkSizeInBytes, READ_BODY_TIMEOUT, tag);
}
else
{
chunkedTransferStage = CHUNKED_STAGE_FOOTER;
asyncSocket.Read(AsyncSocket.CRLFData, READ_FOOTER_TIMEOUT, tag);
}
}
else if (chunkedTransferStage == CHUNKED_STAGE_DATA)
{
// Write the data to log (excluding trailing CRLF)
try
{
String str = Encoding.UTF8.GetString(data, 0, data.Length - 2);
LogMessage(str);
}
catch
{
LogError("Cannot convert chunk to UTF-8 string");
}
chunkedTransferStage = CHUNKED_STAGE_SIZE;
asyncSocket.Read(AsyncSocket.CRLFData, READ_CHUNKSIZE_TIMEOUT, tag);
}
else if (chunkedTransferStage == CHUNKED_STAGE_FOOTER)
{
// The data we just downloaded is either a footer, or an empty line (single CRLF)
if (data.Length > 2)
{
LogInfo("Received HTTP Footer:");
LogInfo(Encoding.UTF8.GetString(data));
asyncSocket.Read(AsyncSocket.CRLFData, READ_FOOTER_TIMEOUT, tag);
}
else
{
LogInfo("\r\nDownload complete");
TimeSpan ellapsed = DateTime.Now - startTime;
LogInfo("\r\nTotal Time = {0:N} milliseconds", ellapsed.TotalMilliseconds);
LogInfo("Disconnecting...");
asyncSocket.Close();
}
}
}
}