amqp-ts
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    1.8.0 • Public • Published

    amqp-ts (AMQP TypeScript)

    This is a summary. See the amqp-ts Wiki for the full documentation of the library.

    Table of Contents

    Overview

    Amqp-ts is a library for nodejs that simplifies communication with AMQP message busses written in Typescript. It has been tested on RabbitMQ. It uses the amqplib library by Michael Bridgen (squaremo).

    Important Changes

    Starting in version 0.14 the return type of exchange.rpc and queue.rpc changed from 'Promise < any >' to 'Promise < Message >'.

    Starting in version 0.12 the Message class has been added. It is a more elegant way to send and receive messages. It is the preferred way to deal with sending and receiving messages.

    Defining Features

    • [High level non opinioned library], no need to worry about channels etc.
    • 'Lazy' initialization, async AMQP dependencies are resolved automatically
    • Automatic reconnection, when the connection with the AMQP server fails, the whole connection and configuration is rebuilt automatically
    • Written in typescript, it is compatible with the Typescript 1.6 module type definition resolution for node.js.

    Current status

    The library is considered production ready.

    It does depend on the following npm libraries:

    The DefinitelyTyped tsd tool is used to manage the typescript type definitions.

    Lazy Initialization

    No need to nest functionality, just create a connection, declare your exchanges, queues and bindings and send and receive messages. The library takes care of any direct dependencies.

    If you define an exchange and a queue and bind the queue to the exchange and want to make sure that the queue is connected to the exchange before you send a message to the exchange you can call the connection.completeConfiguration() method and act on the promise it returns.

    ES6/Typescript Example
    import * as Amqp from "amqp-ts";
     
    var connection = new Amqp.Connection("amqp://localhost");
    var exchange = connection.declareExchange("ExchangeName");
    var queue = connection.declareQueue("QueueName");
    queue.bind(exchange);
    queue.activateConsumer((message) => {
        console.log("Message received: " + message.getContent());
    });
     
    // it is possible that the following message is not received because
    // it can be sent before the queue, binding or consumer exist
    var msg = new Amqp.Message("Test");
    exchange.send(msg);
     
    connection.completeConfiguration().then(() => {
        // the following message will be received because
        // everything you defined earlier for this connection now exists
        var msg2 = new Amqp.Message("Test2");
        exchange.send(msg2);
    });
    Javascript Example
    var amqp = require("amqp-ts");
     
    var connection = new amqp.Connection("amqp://localhost");
    var exchange = connection.declareExchange("ExchangeName");
    var queue = connection.declareQueue("QueueName");
    queue.bind(exchange);
    queue.activateConsumer((message) => {
        console.log("Message received: " + message.getContent());
    });
     
    // it is possible that the following message is not received because
    // it can be sent before the queue, binding or consumer exist
    var msg = new amqp.Message("Test");
    exchange.send(msg);
     
    connection.completeConfiguration().then(() => {
        // the following message will be received because
        // everything you defined earlier for this connection now exists
        var msg2 = new amqp.Message("Test2");
        exchange.send(msg2);
    });

    More examples can be found in the tutorials directory.

    Connection Status

    To know the status of the connection: connection.isConnected. Returns true if the connection exists and false, otherwise.

    Events

    #on('open_connection', function() {...})
    

    It's emitted when a connection is concretized and can publish/subscribe in Rabbit Bus.

    #on('close_connection', function() {...})
    

    It's emitted when a connection is closed, after calling the close method.

    #on('lost_connection', function() {...})
    

    It is emitted when the connection is lost and before attempting to re-establish the connection.

    #on('trying_connect', function() {...})
    

    It is emitted during the time that try re-establish the connection.

    #on('re_established_connection', function() {...})
    

    It is emitted when the connection is re-established.

    #on('error_connection', function(err) {...})
    

    It's emitted when a error is registered during the connection.

    Automatic Reconnection

    When the library detects that the connection with the AMQP server is lost, it tries to automatically reconnect to the server.

    What's new

    version 1.4.0

    • now you can return a Promise with queue.activateConsumer for RPC's. The result of the resolved Promise will be returned to the RPC caller.

    version 1.3.0

    • added noCreate creation option property for Exchange and Queue (expects the exchange or queue to already exist in AMQP)
    • improved unit tests

    version 1.2.0

    • added name property for Exchange and Queue and type property for Exchange
    • improved consumer cleanup for Exchange and Queue methods close and delete

    version 1.1.1

    • added the prefetch option to DeclarationOptions in the amqp-ts.d.ts file

    version 1.1.0

    • fixed incorrect implementation of nack, syntax is now in line with amqplib nack

    version 1.0.1

    • fixed bug in automatic reconnect (exponential growth of retries hanging the application)

    version 1.0.0

    version 0.14.4

    • fixed error when using node.js version 0.10.x: path library does not have a method parse in 0.10.x

    version 0.14.3

    • improved readability of readme.md on npmjs

    version 0.14.2

    • multiple calls of exchange.close, exchange.delete, queue.close and queue.delete return the same promise (and are thereby executed only once)

    version 0.14.1

    • added extra promise rejection handling for exchange.close, exchange.delete, queue.close and queue.delete

    version 0.14.0

    version 0.13.0

    • skipped to avoid bad luck :)

    version 0.12.0

    version 0.11.0

    • revised amqp-ts logging, see Logging in the wiki for more details
    • fixed bug in tutorials library reference

    version 0.10.4

    • added amqp-ts examples for the RabbitMQ tutorials
    • fixed a bug in the queue.rpc
    • fixed documentation errors

    version 0.10.3

    • Moved the documentation to the wiki,only the 'Overview', 'What's new' and 'Roadmap' stay in the readme.md for npmjs and GitHub.
    • Improved the documentation

    version 0.10.2

    version 0.10.1

    • added a 'low level' queue consumer that receives the raw message and can 'ack' or 'nack' these messages itself
    • cleanup integration tests
    • readme update and fixes

    version 0.10

    version 0.9.4 & 0.9.5

    • small code cleanup: defined optional parameter default values in typescript
    • fixed a few bugs when publishing a message to an exchange after a disconnect/reconnect

    version 0.9.3

    • Added this section
    • Added the roadmap section
    • Improved the winston logging messages

    Roadmap

    The roadmap section describes things that I want to add or change in the (hopefully near) future.

    • Better source code documentation, maybe even use jsdoc or tsdoc to generate the api documentation

    Install

    npm i amqp-ts

    DownloadsWeekly Downloads

    8,318

    Version

    1.8.0

    License

    MIT

    Unpacked Size

    195 kB

    Total Files

    42

    Last publish

    Collaborators

    • abreits