HTTPS: Keep-Alive connection to downstream servers.

Reset status = 0 when entering s_status state in htparse_run

examples/htparse/htparse.c

@@ -1118,6 +1118,7 @@ htparser_run(htparser * p, htparse_hooks * hooks, const char * data, size_t len)
                         if (p->type == htp_type_request) {
                             p->state = s_spaces_after_digit;
                         } else if (p->type == htp_type_response) {
+                            p->status = 0;
                             p->state = s_status;
                         }
 

examples/shrpx_downstream.cc

@@ -42,6 +42,7 @@ Downstream::Downstream(Upstream *upstream, int stream_id, int priority)
     bev_(0),
     stream_id_(stream_id),
     priority_(priority),
+    counter_(1),
     ioctrl_(0),
     request_state_(INITIAL),
     request_major_(1),
@@ -53,6 +54,7 @@ Downstream::Downstream(Upstream *upstream, int stream_id, int priority)
     response_major_(1),
     response_minor_(1),
     chunked_response_(false),
+    response_connection_close_(false),
     response_htp_(htparser_new()),
     response_body_buf_(0)
 {
@@ -82,6 +84,41 @@ Downstream::~Downstream()
   }
 }
 
+int Downstream::get_counter() const
+{
+  return counter_;
+}
+
+void Downstream::reuse(int stream_id)
+{
+  stream_id_ = stream_id;
+  ++counter_;
+  request_state_ = INITIAL;
+}
+
+void Downstream::idle()
+{
+  stream_id_ = -1;
+  priority_ = 0;
+  ioctrl_.force_resume_read();
+  request_state_ = IDLE;
+  request_method_.clear();
+  request_path_.clear();
+  request_major_ = 1;
+  request_minor_ = 1;
+  chunked_request_ = false;
+  request_connection_close_ = false;
+  request_headers_.clear();
+
+  response_state_ = INITIAL;
+  response_http_status_ = 0;
+  response_major_ = 1;
+  response_minor_ = 1;
+  chunked_response_ = false;
+  response_connection_close_ = false;
+  response_headers_.clear();
+}
+
 void Downstream::pause_read(IOCtrlReason reason)
 {
   ioctrl_.pause_read(reason);
@@ -110,7 +147,7 @@ void check_transfer_encoding_chunked(bool *chunked,
 } // namespace
 
 namespace {
-void check_request_connection(bool *connection_close,
+void check_connection_close(bool *connection_close,
                             const Headers::value_type &item)
 {
   if(util::strieq(item.first.c_str(), "connection")) {
@@ -134,7 +171,7 @@ void Downstream::set_last_request_header_value(const std::string& value)
   Headers::value_type &item = request_headers_.back();
   item.second = value;
   check_transfer_encoding_chunked(&chunked_request_, item);
-  check_request_connection(&request_connection_close_, item);
+  check_connection_close(&request_connection_close_, item);
 }
 
 void Downstream::set_request_method(const std::string& method)
@@ -255,7 +292,9 @@ int Downstream::push_request_headers()
     }
     hdrs += "\r\n";
   }
+  if(request_connection_close_) {
     hdrs += "Connection: close\r\n";
+  }
   if(!xff_found) {
     hdrs += "X-Forwarded-For: ";
     hdrs += upstream_->get_client_handler()->get_ipaddr();
@@ -327,6 +366,7 @@ void Downstream::set_last_response_header_value(const std::string& value)
   Headers::value_type &item = response_headers_.back();
   item.second = value;
   check_transfer_encoding_chunked(&chunked_response_, item);
+  check_connection_close(&response_connection_close_, item);
 }
 
 unsigned int Downstream::get_response_http_status() const
@@ -364,6 +404,11 @@ bool Downstream::get_chunked_response() const
   return chunked_response_;
 }
 
+bool Downstream::get_response_connection_close() const
+{
+  return response_connection_close_;
+}
+
 namespace {
 int htp_hdrs_completecb(htparser *htp)
 {

examples/shrpx_downstream.h

@@ -57,6 +57,9 @@ public:
   void pause_read(IOCtrlReason reason);
   bool resume_read(IOCtrlReason reason);
   void force_resume_read();
+  void idle();
+  void reuse(int stream_id);
+  int get_counter() const;
   // downstream request API
   const Headers& get_request_headers() const;
   void add_request_header(const std::string& name, const std::string& value);
@@ -78,7 +81,8 @@ public:
     HEADER_COMPLETE,
     MSG_COMPLETE,
     STREAM_CLOSED,
-    CONNECT_FAIL
+    CONNECT_FAIL,
+    IDLE
   };
   void set_request_state(int state);
   int get_request_state() const;
@@ -93,6 +97,7 @@ public:
   int get_response_major() const;
   int get_response_minor() const;
   bool get_chunked_response() const;
+  bool get_response_connection_close() const;
   int parse_http_response();
   void set_response_state(int state);
   int get_response_state() const;
@@ -103,6 +108,7 @@ private:
   bufferevent *bev_;
   int32_t stream_id_;
   int priority_;
+  int counter_;
   IOControl ioctrl_;
   int request_state_;
   std::string request_method_;
@@ -118,6 +124,7 @@ private:
   int response_major_;
   int response_minor_;
   bool chunked_response_;
+  bool response_connection_close_;
   Headers response_headers_;
   htparser *response_htp_;
   // This buffer is used to temporarily store downstream response

examples/shrpx_https_upstream.cc

@@ -76,8 +76,14 @@ int htp_msg_begin(htparser *htp)
   HttpsUpstream *upstream;
   upstream = reinterpret_cast<HttpsUpstream*>(htparser_get_userdata(htp));
   upstream->reset_current_header_length();
-  Downstream *downstream = new Downstream(upstream, 0, 0);
+  Downstream *downstream = upstream->get_top_downstream();
+  if(downstream) {
+    // Keep-Alived connection
+    downstream->reuse(0);
+  } else {
+    downstream = new Downstream(upstream, 0, 0);
     upstream->add_downstream(downstream);
+  }
   return 0;
 }
 } // namespace
@@ -160,12 +166,14 @@ int htp_hdrs_completecb(htparser *htp)
   downstream->push_request_headers();
   downstream->set_request_state(Downstream::HEADER_COMPLETE);
 
+  if(downstream->get_counter() == 1) {
     int rv = downstream->start_connection();
     if(rv != 0) {
       LOG(ERROR) << "Upstream connection failed";
       downstream->set_request_state(Downstream::CONNECT_FAIL);
       return 1;
     }
+  }
   return 0;
 }
 } // namespace
@@ -298,12 +306,21 @@ void https_downstream_readcb(bufferevent *bev, void *ptr)
   Downstream *downstream = reinterpret_cast<Downstream*>(ptr);
   HttpsUpstream *upstream;
   upstream = static_cast<HttpsUpstream*>(downstream->get_upstream());
+  if(downstream->get_request_state() == Downstream::IDLE) {
+    upstream->pop_downstream();
+    delete downstream;
+    return;
+  }
   int rv = downstream->parse_http_response();
   if(rv == 0) {
     if(downstream->get_response_state() == Downstream::MSG_COMPLETE) {
       assert(downstream == upstream->get_top_downstream());
+      if(downstream->get_response_connection_close()) {
         upstream->pop_downstream();
         delete downstream;
+      } else {
+        downstream->idle();
+      }
       upstream->resume_read(SHRPX_MSG_BLOCK);
     } else {
       ClientHandler *handler = upstream->get_client_handler();
@@ -344,12 +361,12 @@ void https_downstream_eventcb(bufferevent *bev, short events, void *ptr)
       LOG(INFO) << "Downstream connection established. downstream "
                 << downstream;
     }
-  }
-  if(events & BEV_EVENT_EOF) {
+  } else if(events & BEV_EVENT_EOF) {
     if(ENABLE_LOG) {
       LOG(INFO) << "Downstream EOF. stream_id="
                 << downstream->get_stream_id();
     }
+    if(downstream->get_request_state() != Downstream::IDLE) {
       if(downstream->get_response_state() == Downstream::HEADER_COMPLETE) {
         // Server may indicate the end of the request by EOF
         if(ENABLE_LOG) {
@@ -366,6 +383,7 @@ void https_downstream_eventcb(bufferevent *bev, short events, void *ptr)
         }
         upstream->error_reply(502);
       }
+    }
     upstream->pop_downstream();
     delete downstream;
     upstream->resume_read(SHRPX_MSG_BLOCK);