asio_service support stream mode (#527)

* asio_service support stream mode
1. set TCP_NODELAY = true this can be set after the socket open. So we can't set it in constructor. (async_connect will open the socket)
2. does the order of calling all the when_done matter when error occur? in write path when_done(error triggered) -> close_socket(in destructor) in read path close_socket(directly call) -> when_done(error triggered)
3. keep the old path for all request if stream_mode_ = false

already addressed all the comment.

* handle comments

* fix error

* error handle

* move all function call out of lock

* [Refactoring] renaming, comments, indent

---------

Co-authored-by: lihzeng <[email protected]>
Co-authored-by: Jung-Sang Ahn <[email protected]>

.github/workflows/cmake.yml

@@ -9,6 +9,7 @@ on:
   pull_request:
     branches:
       - master
+      - streaming
 
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)

include/libnuraft/asio_service_options.hxx

@@ -125,6 +125,7 @@ struct asio_service_options {
         , crc_on_entire_message_(false)
         , crc_on_payload_(false)
         , corrupted_msg_handler_(nullptr)
+        , streaming_mode_(false)
         {}
 
     /**
@@ -276,6 +277,13 @@ struct asio_service_options {
      */
     std::function< void( std::shared_ptr<buffer>,
                          std::shared_ptr<buffer> ) > corrupted_msg_handler_;
+
+    /**
+     * If `true`,  NuRaft will use streaming mode, which allows it to send
+     * subsequent requests without waiting for the response to previous requests.
+     * The order of responses will be identical to the order of requests.
+     */
+    bool streaming_mode_;
 };
 
 }

scripts/test/runtests.sh

@@ -9,3 +9,4 @@ set -e
 ./tests/raft_server_test --abort-on-failure
 ./tests/failure_test --abort-on-failure
 ./tests/asio_service_test --abort-on-failure
+./tests/asio_service_stream_test --abort-on-failure