private void SavePendingRequest(httpRequestType incomingRequest)
{
SqlCommand cmd = s_connection.CreateCommand();
cmd.CommandText = "sp_AddOrUpdatePendingRequest";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Transaction = s_transaction;
cmd.Parameters.AddWithValue("@ConversationHandle", s_currentConversation.Handle);
cmd.Parameters.AddWithValue("@RetriesUsed", ++m_numRetriesUsed);
if (s_msgReceived.Type == x_httpRequestMessageType)
{
MemoryStream stream = new MemoryStream();
XmlSerializer xs = new XmlSerializer(typeof(httpRequestType));
xs.Serialize(stream, incomingRequest);
cmd.Parameters.AddWithValue("@RequestBody", stream.ToArray());
}
else
{
cmd.Parameters.Add("@RequestBody", SqlDbType.VarBinary).Value = DBNull.Value;
}
if (m_lastError == null)
cmd.Parameters.AddWithValue("@Status", DBNull.Value);
else
cmd.Parameters.AddWithValue("@Status", m_lastError);
try
{
cmd.ExecuteNonQuery();
}
catch (SqlException e)
{
SqlContext.Pipe.Send(e.Message);
}
}
public void OnHttpRequest(
Message msgReceived,
SqlConnection connection,
SqlTransaction transaction)
{
s_connection = connection;
s_transaction = transaction;
s_currentConversation = msgReceived.Conversation;
s_msgReceived = msgReceived;
try
{
XmlSerializer xs = new XmlSerializer(typeof(httpRequestType));
httpRequestType request = (httpRequestType)xs.Deserialize(msgReceived.Body);
ServiceRequest(request);
}
catch (Exception e)
{
SqlContext.Pipe.Send(e.StackTrace);
if (connection.State == ConnectionState.Open)
{
msgReceived.Conversation.EndWithError(1, e.Message + "\n" + e.StackTrace, connection, transaction);
}
}
}
private RequestFilterAction MatchRequestFilter(httpRequestType incomingRequest)
{
SqlCommand cmd = s_connection.CreateCommand();
cmd.CommandText = "sp_MatchRequestFilter";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Transaction = s_transaction;
SqlParameter prmMethod = cmd.Parameters.AddWithValue("@Method", incomingRequest.method);
SqlParameter prmUrl = cmd.Parameters.AddWithValue("@Url", incomingRequest.url);
SqlDataReader reader = cmd.ExecuteReader();
if (!reader.Read())
{
reader.Close();
return RequestFilterAction.Deny;
}
RequestFilterAction action = (RequestFilterAction)reader.GetByte(0);
if (!reader.IsDBNull(1))
m_timeout = TimeSpan.FromSeconds(reader.GetInt32(1));
if (!reader.IsDBNull(2))
m_numRetries = (int) reader.GetByte(2);
if (!reader.IsDBNull(3))
m_retryDelay = reader.GetInt32(3);
if (!reader.IsDBNull(4))
m_backoffFactor = reader.GetFloat(4);
reader.Close();
return action;
}
private void ServiceRequest(httpRequestType incomingRequest)
{
RequestFilterAction reqAction = MatchRequestFilter(incomingRequest);
switch (reqAction)
{
case RequestFilterAction.Deny:
ErrorConversation(2, "Proxy does not accept this type of request to given URL.");
return;
}
HttpWebRequest outgoingRequest = CreateWebRequest(incomingRequest);
if (outgoingRequest == null)
{
SavePendingRequest(incomingRequest);
BeginTimer();
return;
}
HttpWebResponse incomingResponse = null;
ResponseFilterAction respAction = TryWebRequest(outgoingRequest, out incomingResponse);
SqlContext.Pipe.Send(respAction.ToString());
switch (respAction)
{
case ResponseFilterAction.Respond:
httpResponseType outgoingResponse = CreateBrokerResponse(incomingResponse);
SendResponse(outgoingResponse);
EndConversation();
// Deletes the pending request, if there was one stored...
DeletePendingRequest();
break;
case ResponseFilterAction.Retry:
if (m_numRetries == m_numRetriesUsed)
{
ErrorConversation(5, m_lastError);
}
else
{
SavePendingRequest(incomingRequest);
BeginTimer();
}
break;
case ResponseFilterAction.Error:
if (incomingResponse != null)
{
ErrorConversation(4, m_lastError);
}
break;
}
}
public void OnTimer(
Message msgReceived,
SqlConnection connection,
SqlTransaction transaction)
{
s_connection = connection;
s_transaction = transaction;
s_currentConversation = msgReceived.Conversation;
s_msgReceived = msgReceived;
httpRequestType pendingRequest = GetPendingRequest();
if (pendingRequest == null)
{
ErrorConversation(6, "Your pending request was mysteriously lost.");
return;
}
SqlContext.Pipe.Send("retrieved: " + pendingRequest.url);
SqlContext.Pipe.Send("num used: " + m_numRetriesUsed);
ServiceRequest(pendingRequest);
}
private httpRequestType GetPendingRequest()
{
SqlCommand cmd = s_connection.CreateCommand();
cmd.CommandText = @"SELECT RequestBody, RetriesUsed FROM PendingRequest WHERE ConversationHandle = @ConversationHandle";
cmd.Transaction = s_transaction;
cmd.Parameters.AddWithValue("@ConversationHandle", s_currentConversation.Handle);
SqlDataReader reader = cmd.ExecuteReader();
if (!reader.Read())
{
reader.Close();
return null;
}
SqlBytes requestBytes = reader.GetSqlBytes(0);
XmlSerializer xs = new XmlSerializer(typeof(httpRequestType));
httpRequestType pendingRequest = xs.Deserialize(requestBytes.Stream) as httpRequestType;
m_numRetriesUsed = (int) reader.GetByte(1);
reader.Close();
return pendingRequest;
}
private HttpWebRequest CreateWebRequest(httpRequestType incomingRequest)
{
HttpWebRequest outgoingRequest;
outgoingRequest = (HttpWebRequest)HttpWebRequest.Create(incomingRequest.url);
outgoingRequest.Method = incomingRequest.method;
outgoingRequest.Timeout = (int) m_timeout.TotalMilliseconds;
if (incomingRequest.protocolVersion != null)
{
try
{
string[] s = incomingRequest.protocolVersion.Split(new char[] { '/' });
if (s.Length > 1)
{
outgoingRequest.ProtocolVersion = new Version(s[1]);
}
}
catch
{ }
}
outgoingRequest.ContentLength = incomingRequest.body.Length;
if (incomingRequest.headers != null)
{
foreach (headerType h in incomingRequest.headers)
{
SqlContext.Pipe.Send(h.name + ": " + h.value);
switch (h.name.ToLowerInvariant())
{
case "host":
case "date":
case "range":
break;
case "accept":
outgoingRequest.Accept = h.value;
break;
case "connection":
outgoingRequest.Connection = h.value;
break;
//case "content-length":
// outgoingRequest.ContentLength = Int32.Parse(h.value);
// break;
case "content-type":
outgoingRequest.ContentType = h.value;
break;
case "expect":
outgoingRequest.Expect = h.value;
break;
case "if-modified-since":
outgoingRequest.IfModifiedSince = DateTime.Parse(h.value);
break;
case "referer":
outgoingRequest.Referer = h.value;
break;
case "transfer-encoding":
outgoingRequest.TransferEncoding = h.value;
break;
case "user-agent":
outgoingRequest.UserAgent = h.value;
break;
default:
outgoingRequest.Headers[h.name] = h.value;
break;
}
}
}
byte[] buffer = incomingRequest.body;
if (buffer != null && buffer.Length > 0)
{
try
{
Stream body = outgoingRequest.GetRequestStream();
body.Write(buffer, 0, buffer.Length);
body.Close();
}
catch (WebException we)
{
// The web service isn't available
m_lastError = we.Message;
return null;
}
}
return outgoingRequest;
}
