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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.
*
*/
/**
* server.cpp
*
* This program is one of two programs that illustrate the
* request/response pattern.
*
*
* client.cpp
*
* A client application that sends messages to the "amq.direct"
* exchange, using the routing key "request" to route messages to
* the server.
*
* Each instance of the client creates its own private response
* queue, binding it to the "amq.direct" exchange using it's
* session identifier as the routing key, and places its session
* identifier in the "reply-to" property of each message it sends.
*
*
* server.cpp (this program)
*
* A service that accepts messages from a request queue, converts
* their content to upper case, and sends the result to the
* original sender.
*
* This program creates a request queue, binds it to "amq.direct"
* using the routing key "request", then receives messages from
* the request queue. Each incoming message is converted to upper
* case, then sent to the "amq.direct" exchange using the
* request's reply-to property as the routing key for the
* response.
*
*
*/
#include <qpid/client/Connection.h>
#include <qpid/client/Session.h>
#include <qpid/client/AsyncSession.h>
#include <qpid/client/Message.h>
#include <qpid/client/MessageListener.h>
#include <qpid/client/SubscriptionManager.h>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <string>
using namespace qpid::client;
using namespace qpid::framing;
using std::stringstream;
using std::string;
class Listener : public MessageListener{
private:
SubscriptionManager& subscriptions;
AsyncSession asyncSession;
public:
Listener(SubscriptionManager& subscriptions, Session& session);
virtual void received(Message& message);
};
Listener::Listener(SubscriptionManager& subs, Session& session)
: subscriptions(subs), asyncSession(session)
{}
void Listener::received(Message& request) {
Message response;
// Get routing key for response from the request's replyTo property
string routingKey;
if (request.getMessageProperties().hasReplyTo()) {
routingKey = request.getMessageProperties().getReplyTo().getRoutingKey();
} else {
std::cout << "Error: " << "No routing key for request (" << request.getData() << ")" << std::endl;
return;
}
std::cout << "Request: " << request.getData() << " (" <<routingKey << ")" << std::endl;
// Transform message content to upper case
std::string s = request.getData();
std::transform (s.begin(), s.end(), s.begin(), toupper);
response.setData(s);
// Send it back to the user
response.getDeliveryProperties().setRoutingKey(routingKey);
// Asynchronous transfer sends messages as quickly as
// possible without waiting for confirmation.
asyncSession.messageTransfer(arg::content=response, arg::destination="amq.direct");
}
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;
try {
connection.open(host, port);
Session session = connection.newSession();
//--------- Main body of program --------------------------------------------
// Create a request queue for clients to use when making
// requests.
string request_queue = "request";
// Use the name of the request queue as the routing key
session.queueDeclare(arg::queue=request_queue);
session.exchangeBind(arg::exchange="amq.direct", arg::queue=request_queue, arg::bindingKey=request_queue);
// Create a listener and subscribe it to the request_queue
std::cout << "Activating request queue listener for: " << request_queue << std::endl;
SubscriptionManager subscriptions(session);
Listener listener(subscriptions, session);
subscriptions.subscribe(listener, request_queue);
// Deliver messages until the subscription is cancelled
// by Listener::received()
std::cout << "Waiting for requests" << std::endl;
subscriptions.run();
//-----------------------------------------------------------------------------
connection.close();
return 0;
} catch(const std::exception& error) {
std::cout << error.what() << std::endl;
}
return 1;
}
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