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/*
*
* 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.
*
*/
/**
* client.cpp
*
* This program is one of two programs that illustrate the
* request/response pattern.
*
* client.cpp (this program)
*
* Make requests of a service, print the response.
*
* service.cpp
*
* Accept requests, reverse the letters in each message, and
* return it as a response.
*
*/
#include <qpid/client/Connection.h>
#include <qpid/client/Dispatcher.h>
#include <qpid/client/Session.h>
#include <qpid/client/Message.h>
#include <qpid/client/MessageListener.h>
#include <unistd.h>
#include <cstdlib>
#include <iostream>
#include <sstream>
using namespace qpid::client;
using namespace qpid::framing;
class Listener : public MessageListener{
private:
Session session;
std::string destination_name;
Dispatcher dispatcher;
int counter;
public:
Listener(Session& session, string destination_name):
session(session),
destination_name(destination_name),
dispatcher(session),
counter(0)
{};
virtual void listen();
virtual void wait();
virtual void received(Message& message);
~Listener() { };
};
void Listener::listen() {
std::cout << "Activating response queue listener for: " <<destination_name << std::endl;
session.messageSubscribe(arg::queue=destination_name, arg::destination=destination_name);
session.messageFlow(arg::destination=destination_name, arg::unit=MESSAGE_CREDIT, arg::value=1);
session.messageFlow(arg::destination=destination_name, arg::unit=BYTE_CREDIT, arg::value=UNLIMITED_CREDIT);
dispatcher.listen(destination_name, this);
}
void Listener::wait() {
std::cout << "Waiting for all responses to arrive ..." << std::endl;
dispatcher.run();
}
void Listener::received(Message& message) {
std::cout << "Response: " << message.getData() << std::endl;
++ counter;
if (counter > 3) {
std::cout << "Shutting down listener for " << destination_name << std::endl;
dispatcher.stop();
}
}
using std::stringstream;
using std::string;
int main(int argc, char** argv) {
const char* host = argc>1 ? argv[1] : "127.0.0.1";
int port = argc>2 ? atoi(argv[2]) : 5672;
Connection connection;
Message request;
try {
connection.open(host, port);
Session session = connection.newSession();
//--------- Main body of program --------------------------------------------
// Create a response queue so the server can send us responses
// to our requests. Use the client's session ID as the name
// of the response queue.
stringstream response_queue;
response_queue << "client" << session.getId().getName();
// Use the name of the response queue as the routing key
session.queueDeclare(arg::queue=response_queue.str());
session.exchangeBind(arg::exchange="amq.direct", arg::queue=response_queue.str(), arg::bindingKey=response_queue.str());
// Create a listener for the response queue and start listening.
Listener listener(session, response_queue.str());
listener.listen();
// The routing key for the request queue is simply
// "request", and all clients use the same routing key.
//
// Each client sends the name of their own response queue so
// the service knows where to route messages.
request.getDeliveryProperties().setRoutingKey("request");
request.getMessageProperties().setReplyTo(ReplyTo("amq.direct", response_queue.str()));
// Now send some requests ...
string s[] = {
"Twas brillig, and the slithy toves",
"Did gire and gymble in the wabe.",
"All mimsy were the borogroves,",
"And the mome raths outgrabe."
};
for (int i=0; i<4; i++) {
request.setData(s[i]);
// Asynchronous transfer sends messages as quickly as
// possible without waiting for confirmation.
async(session).messageTransfer(arg::content=request, arg::destination="amq.direct");
std::cout << "Request: " << s[i] << std::endl;
}
// And wait for any outstanding responses to arrive
listener.wait();
//-----------------------------------------------------------------------------
connection.close();
return 0;
} catch(const std::exception& error) {
std::cout << error.what() << std::endl;
}
return 1;
}
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