| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| // |
| // C++11 or greater |
| // |
| // A multi-threaded client that calls proton::container::run() in one thread, sends |
| // messages in another and receives messages in a third. |
| // |
| // Note this client does not deal with flow-control. If the sender is faster |
| // than the receiver, messages will build up in memory on the sending side. |
| // See @ref multithreaded_client_flow_control.cpp for a more complex example with |
| // flow control. |
| // |
| // NOTE: no proper error handling |
| |
| #include <proton/connection.hpp> |
| #include <proton/connection_options.hpp> |
| #include <proton/container.hpp> |
| #include <proton/message.hpp> |
| #include <proton/messaging_handler.hpp> |
| #include <proton/receiver.hpp> |
| #include <proton/sender.hpp> |
| #include <proton/work_queue.hpp> |
| |
| #include <condition_variable> |
| #include <iostream> |
| #include <mutex> |
| #include <queue> |
| #include <sstream> |
| #include <string> |
| #include <thread> |
| |
| // Lock output from threads to avoid scrambling |
| std::mutex out_lock; |
| #define OUT(x) do { std::lock_guard<std::mutex> l(out_lock); x; } while (false) |
| |
| // Handler for a single thread-safe sending and receiving connection. |
| class client : public proton::messaging_handler { |
| // Invariant |
| const std::string url_; |
| const std::string address_; |
| |
| // Only used in proton handler thread |
| proton::sender sender_; |
| |
| // Shared by proton and user threads, protected by lock_ |
| std::mutex lock_; |
| proton::work_queue *work_queue_; |
| std::condition_variable sender_ready_; |
| std::queue<proton::message> messages_; |
| std::condition_variable messages_ready_; |
| |
| public: |
| client(const std::string& url, const std::string& address) : url_(url), address_(address), work_queue_(0) {} |
| |
| // Thread safe |
| void send(const proton::message& msg) { |
| // Use [=] to copy the message, we cannot pass it by reference since it |
| // will be used in another thread. |
| work_queue()->add([=]() { sender_.send(msg); }); |
| } |
| |
| // Thread safe |
| proton::message receive() { |
| std::unique_lock<std::mutex> l(lock_); |
| while (messages_.empty()) messages_ready_.wait(l); |
| auto msg = std::move(messages_.front()); |
| messages_.pop(); |
| return msg; |
| } |
| |
| // Thread safe |
| void close() { |
| work_queue()->add([=]() { sender_.connection().close(); }); |
| } |
| |
| private: |
| |
| proton::work_queue* work_queue() { |
| // Wait till work_queue_ and sender_ are initialized. |
| std::unique_lock<std::mutex> l(lock_); |
| while (!work_queue_) sender_ready_.wait(l); |
| return work_queue_; |
| } |
| |
| // == messaging_handler overrides, only called in proton handler thread |
| |
| // Note: this example creates a connection when the container starts. |
| // To create connections after the container has started, use |
| // container::connect(). |
| // See @ref multithreaded_client_flow_control.cpp for an example. |
| void on_container_start(proton::container& cont) override { |
| cont.connect(url_); |
| } |
| |
| void on_connection_open(proton::connection& conn) override { |
| conn.open_sender(address_); |
| conn.open_receiver(address_); |
| } |
| |
| void on_sender_open(proton::sender& s) override { |
| // sender_ and work_queue_ must be set atomically |
| std::lock_guard<std::mutex> l(lock_); |
| sender_ = s; |
| work_queue_ = &s.work_queue(); |
| sender_ready_.notify_all(); |
| } |
| |
| void on_message(proton::delivery& dlv, proton::message& msg) override { |
| std::lock_guard<std::mutex> l(lock_); |
| messages_.push(msg); |
| messages_ready_.notify_all(); |
| } |
| |
| void on_error(const proton::error_condition& e) override { |
| OUT(std::cerr << "unexpected error: " << e << std::endl); |
| exit(1); |
| } |
| }; |
| |
| int main(int argc, const char** argv) { |
| try { |
| if (argc != 4) { |
| std ::cerr << |
| "Usage: " << argv[0] << " CONNECTION-URL AMQP-ADDRESS MESSAGE-COUNT\n" |
| "CONNECTION-URL: connection address, e.g.'amqp://127.0.0.1'\n" |
| "AMQP-ADDRESS: AMQP node address, e.g. 'examples'\n" |
| "MESSAGE-COUNT: number of messages to send\n"; |
| return 1; |
| } |
| const char *url = argv[1]; |
| const char *address = argv[2]; |
| int n_messages = atoi(argv[3]); |
| |
| client cl(url, address); |
| proton::container container(cl); |
| std::thread container_thread([&]() { container.run(); }); |
| |
| std::thread sender([&]() { |
| for (int i = 0; i < n_messages; ++i) { |
| proton::message msg(std::to_string(i + 1)); |
| cl.send(msg); |
| OUT(std::cout << "sent \"" << msg.body() << '"' << std::endl); |
| } |
| }); |
| |
| int received = 0; |
| std::thread receiver([&]() { |
| for (int i = 0; i < n_messages; ++i) { |
| auto msg = cl.receive(); |
| OUT(std::cout << "received \"" << msg.body() << '"' << std::endl); |
| ++received; |
| } |
| }); |
| |
| sender.join(); |
| receiver.join(); |
| cl.close(); |
| container_thread.join(); |
| std::cout << received << " messages sent and received" << std::endl; |
| |
| return 0; |
| } catch (const std::exception& e) { |
| std::cerr << e.what() << std::endl; |
| } |
| |
| return 1; |
| } |