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Chapter 4. Examples

This chapter demonstrates the use of AMQ JavaScript through example programs. To run them, make sure you have completed the steps in the Chapter 2, Installation chapter for your environment and you have a running and configured broker.

See the Rhea examples for more sample programs. Note that some of the sample programs there require the minimist package in order to parse command-line options.

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
};

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. 

$ 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
};

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. 

$ node receive.js amqp://localhost queue1