client.cpp

The client part of a request-response example.

The client part of a request-response example. Sends requests and prints out responses. Requires an intermediary that supports the AMQP 1.0 dynamic nodes on which the responses are received. The requests are sent through the 'examples' node.

/*
 *
 * 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
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 * KIND, either express or implied.  See the License for the
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#include "options.hpp"
#include <proton/connection.hpp>
#include <proton/container.hpp>
#include <proton/delivery.hpp>
#include <proton/message.hpp>
#include <proton/messaging_handler.hpp>
#include <proton/receiver_options.hpp>
#include <proton/source_options.hpp>
#include <proton/tracker.hpp>
 
#include <iostream>
#include <vector>
 
 
using proton::receiver_options;
using proton::source_options;
 
class client : public proton::messaging_handler {
  private:
    std::string url;
    std::vector<std::string> requests;
    proton::sender sender;
    proton::receiver receiver;
 
  public:
    client(const std::string &u, const std::vector<std::string>& r) : url(u), requests(r) {}
 
    void on_container_start(proton::container &c) override {
        sender = c.open_sender(url);
        // Create a receiver requesting a dynamically created queue
        // for the message source.
        receiver_options opts = receiver_options().source(source_options().dynamic(true));
        receiver = sender.connection().open_receiver("", opts);
    }
 
    void send_request() {
        proton::message req;
        req.body(requests.front());
        req.reply_to(receiver.source().address());
        sender.send(req);
    }
 
    void on_receiver_open(proton::receiver &) override {
        send_request();
    }
 
    void on_message(proton::delivery &d, proton::message &response) override {
        if (requests.empty()) return; // Spurious extra message!
 
        std::cout << requests.front() << " => " << response.body() << std::endl;
        requests.erase(requests.begin());
 
        if (!requests.empty()) {
            send_request();
        } else {
            d.connection().close();
        }
    }
};
 
int main(int argc, char **argv) {
    std::string url("127.0.0.1:5672/examples");
    example::options opts(argc, argv);
 
    opts.add_value(url, 'a', "address", "connect and send to URL", "URL");
 
    try {
        opts.parse();
 
        std::vector<std::string> requests;
        requests.push_back("Twas brillig, and the slithy toves");
        requests.push_back("Did gire and gymble in the wabe.");
        requests.push_back("All mimsy were the borogroves,");
        requests.push_back("And the mome raths outgrabe.");
 
        client c(url, requests);
        proton::container(c).run();
 
        return 0;
    } catch (const example::bad_option& e) {
        std::cout << opts << std::endl << e.what() << std::endl;
    } catch (const std::exception& e) {
        std::cerr << e.what() << std::endl;
    }
 
    return 1;
}