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Chapter 4. Examples

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This chapter demonstrates the use of Red Hat build of Rhea through example programs.

For more examples, see the Rhea example suite and the Rhea examples.

4.1. Sending messages

This client program connects to a server using <connection-url>, creates a sender for target <address>, sends a message containing <message-body>, closes the connection, and exits.

Example: Sending messages

"use strict";

var rhea = require("rhea");
var url = require("url");

if (process.argv.length !== 5) {
    console.error("Usage: send.js <connection-url> <address> <message-body>");
    process.exit(1);
}

var conn_url = url.parse(process.argv[2]);
var address = process.argv[3];
var message_body = process.argv[4];

var container = rhea.create_container();

container.on("sender_open", function (event) {
    console.log("SEND: Opened sender for target address '" +
                event.sender.target.address + "'");
});

container.on("sendable", function (event) {
    var message = {
        body: message_body
    };

    event.sender.send(message);

    console.log("SEND: Sent message '" + message.body + "'");

    event.sender.close();
    event.connection.close();
});

var opts = {
    host: conn_url.hostname,
    port: conn_url.port || 5672,
    // To connect with a user and password:
    // username: "<username>",
    // password: "<password>",
};

var conn = container.connect(opts);
conn.open_sender(address);

Running the example

To run the example program, copy it to a local file and invoke it using the node command. For more information, see Chapter 3, Getting started.

$ node send.js amqp://localhost queue1 hello

4.2. Receiving messages

This client program connects to a server using <connection-url>, creates a receiver for source <address>, and receives messages until it is terminated or it reaches <count> messages.

Example: Receiving messages

"use strict";

var rhea = require("rhea");
var url = require("url");

if (process.argv.length !== 4 && process.argv.length !== 5) {
    console.error("Usage: receive.js <connection-url> <address> [<message-count>]");
    process.exit(1);
}

var conn_url = url.parse(process.argv[2]);
var address = process.argv[3];
var desired = 0;
var received = 0;

if (process.argv.length === 5) {
    desired = parseInt(process.argv[4]);
}

var container = rhea.create_container();

container.on("receiver_open", function (event) {
    console.log("RECEIVE: Opened receiver for source address '" +
                event.receiver.source.address + "'");
});

container.on("message", function (event) {
    var message = event.message;

    console.log("RECEIVE: Received message '" + message.body + "'");

    received++;

    if (received == desired) {
        event.receiver.close();
        event.connection.close();
    }
});

var opts = {
    host: conn_url.hostname,
    port: conn_url.port || 5672,
    // To connect with a user and password:
    // username: "<username>",
    // password: "<password>",
};

var conn = container.connect(opts);
conn.open_receiver(address);

Running the example

To run the example program, copy it to a local file and invoke it using the python command. For more information, see Chapter 3, Getting started.

$ node receive.js amqp://localhost queue1
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