From eb9458bba9fdb966ffcbcc682b34aa46022aad5a Mon Sep 17 00:00:00 2001
From: Tatsuhiro Tsujikawa <tatsuhiro.t@gmail.com>
Date: Tue, 12 Jun 2012 23:02:01 +0900
Subject: [PATCH] Adjust read/write timeout depending on the request/response
 state

---
 examples/shrpx.cc                       |  2 ++
 examples/shrpx_config.h                 |  1 +
 examples/shrpx_downstream.cc            |  4 ++++
 examples/shrpx_downstream_connection.cc | 25 +++++++++++++++++++++++--
 examples/shrpx_downstream_connection.h  |  1 +
 examples/spdycat.cc                     |  3 ++-
 6 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/examples/shrpx.cc b/examples/shrpx.cc
index 686fa4ec..ca814583 100644
--- a/examples/shrpx.cc
+++ b/examples/shrpx.cc
@@ -251,6 +251,8 @@ void fill_default_config()
   mod_config()->downstream_write_timeout.tv_sec = 30;
   mod_config()->downstream_write_timeout.tv_usec = 0;
 
+  mod_config()->downstream_idle_read_timeout.tv_sec = 15;
+
   mod_config()->downstream_host = "localhost";
   mod_config()->downstream_port = 80;
 
diff --git a/examples/shrpx_config.h b/examples/shrpx_config.h
index 9c2bdc8b..97157adc 100644
--- a/examples/shrpx_config.h
+++ b/examples/shrpx_config.h
@@ -64,6 +64,7 @@ struct Config {
   timeval spdy_upstream_write_timeout;
   timeval downstream_read_timeout;
   timeval downstream_write_timeout;
+  timeval downstream_idle_read_timeout;
   size_t num_worker;
   size_t spdy_max_concurrent_streams;
   Config();
diff --git a/examples/shrpx_downstream.cc b/examples/shrpx_downstream.cc
index 64aaf24a..0d5517cb 100644
--- a/examples/shrpx_downstream.cc
+++ b/examples/shrpx_downstream.cc
@@ -254,6 +254,8 @@ bool Downstream::get_output_buffer_full()
   }
 }
 
+// Call this function after this object is attached to
+// Downstream. Otherwise, the program will crash.
 int Downstream::push_request_headers()
 {
   bool xff_found = false;
@@ -317,6 +319,8 @@ int Downstream::push_request_headers()
   bufferevent *bev = dconn_->get_bev();
   evbuffer *output = bufferevent_get_output(bev);
   evbuffer_add(output, hdrs.c_str(), hdrs.size());
+
+  dconn_->start_waiting_response();
   return 0;
 }
 
diff --git a/examples/shrpx_downstream_connection.cc b/examples/shrpx_downstream_connection.cc
index 5bdd7513..ca0c675d 100644
--- a/examples/shrpx_downstream_connection.cc
+++ b/examples/shrpx_downstream_connection.cc
@@ -87,13 +87,29 @@ int DownstreamConnection::attach_downstream(Downstream *downstream)
                     upstream->get_downstream_readcb(),
                     upstream->get_downstream_writecb(),
                     upstream->get_downstream_eventcb(), this);
-
+  // HTTP request/response model, we first issue request to downstream
+  // server, so just enable write timeout here.
   bufferevent_set_timeouts(bev_,
-                           &get_config()->downstream_read_timeout,
+                           0,
                            &get_config()->downstream_write_timeout);
   return 0;
 }
 
+// When downstream request is issued, call this function to set read
+// timeout. We don't know when the request is completely received by
+// the downstream server. This function may be called before that
+// happens. Overall it does not cause problem for most of the time.
+// If the downstream server is too slow to recv/send, the connection
+// will be dropped by read timeout.
+void DownstreamConnection::start_waiting_response()
+{
+  if(bev_) {
+    bufferevent_set_timeouts(bev_,
+                             &get_config()->downstream_read_timeout,
+                             0);
+  }
+}
+
 namespace {
 // Gets called when DownstreamConnection is pooled in ClientHandler.
 void idle_eventcb(bufferevent *bev, short events, void *arg)
@@ -136,6 +152,11 @@ void DownstreamConnection::detach_downstream(Downstream *downstream)
   downstream_ = 0;
   bufferevent_enable(bev_, EV_READ);
   bufferevent_setcb(bev_, 0, 0, idle_eventcb, this);
+  // On idle state, just enable read timeout. Normally idle downstream
+  // connection will get EOF from the downstream server and closed.
+  bufferevent_set_timeouts(bev_,
+                           &get_config()->downstream_idle_read_timeout,
+                           0);
   client_handler_->pool_downstream_connection(this);
 }
 
diff --git a/examples/shrpx_downstream_connection.h b/examples/shrpx_downstream_connection.h
index f866ba08..76a66c66 100644
--- a/examples/shrpx_downstream_connection.h
+++ b/examples/shrpx_downstream_connection.h
@@ -46,6 +46,7 @@ public:
 
   ClientHandler* get_client_handler();
   Downstream* get_downstream();
+  void start_waiting_response();
 private:
   ClientHandler *client_handler_;
   bufferevent *bev_;
diff --git a/examples/spdycat.cc b/examples/spdycat.cc
index 7a21ac93..416c5f6b 100644
--- a/examples/spdycat.cc
+++ b/examples/spdycat.cc
@@ -269,6 +269,7 @@ void on_data_chunk_recv_callback
   std::map<int32_t, Request*>::iterator itr =
     spdySession->streams.find(stream_id);
   if(itr != spdySession->streams.end()) {
+    spdylay_submit_rst_stream(session, stream_id, SPDYLAY_PROTOCOL_ERROR);
     Request *req = (*itr).second;
     if(req->inflater) {
       while(len > 0) {
@@ -387,7 +388,7 @@ void on_stream_close_callback
     (*itr).second->record_complete_time();
     ++spdySession->complete;
     if(spdySession->all_requests_processed()) {
-      spdylay_submit_goaway(session, SPDYLAY_GOAWAY_OK);
+      //spdylay_submit_goaway(session, SPDYLAY_GOAWAY_OK);
     }
   }
 }