@azure/core-amqp

What is @azure/core-amqp?

@azure/core-amqp is a library that provides core functionality for working with the Advanced Message Queuing Protocol (AMQP) in Azure services. It is primarily used as a building block for other Azure SDKs that need to communicate over AMQP, such as Azure Service Bus and Azure Event Hubs.

What are @azure/core-amqp's main functionalities?

AMQP Connection Management

This feature allows you to establish and manage AMQP connections. The code sample demonstrates how to create a connection context and open a connection using a connection string.

const { ConnectionContext } = require('@azure/core-amqp');

async function createConnection() {
  const connectionContext = ConnectionContext.create({
    connectionString: 'your-connection-string',
    options: {}
  });
  await connectionContext.connection.open();
  console.log('Connection established');
  return connectionContext;
}

createConnection().catch(console.error);

AMQP Sender and Receiver

This feature allows you to send and receive messages over AMQP. The code sample demonstrates how to create a sender to send a message and a receiver to receive messages from a specified queue.

const { ConnectionContext, Sender, Receiver } = require('@azure/core-amqp');

async function sendMessage() {
  const connectionContext = await createConnection();
  const sender = new Sender(connectionContext, 'queue-name');
  await sender.send({ body: 'Hello, World!' });
  console.log('Message sent');
}

async function receiveMessage() {
  const connectionContext = await createConnection();
  const receiver = new Receiver(connectionContext, 'queue-name');
  receiver.on('message', (message) => {
    console.log('Received message:', message.body);
  });
}

sendMessage().catch(console.error);
receiveMessage().catch(console.error);

AMQP Error Handling

This feature provides mechanisms for handling errors that occur during AMQP operations. The code sample demonstrates how to handle errors when establishing a connection.

const { ConnectionContext } = require('@azure/core-amqp');

async function createConnectionWithErrorHandling() {
  try {
    const connectionContext = ConnectionContext.create({
      connectionString: 'your-connection-string',
      options: {}
    });
    await connectionContext.connection.open();
    console.log('Connection established');
    return connectionContext;
  } catch (error) {
    console.error('Error establishing connection:', error);
  }
}

createConnectionWithErrorHandling().catch(console.error);

Other packages similar to @azure/core-amqp

amqp10

The 'amqp10' package is a pure JavaScript implementation of the AMQP 1.0 protocol. It provides similar functionalities for managing AMQP connections, sending, and receiving messages. However, it is not specifically tailored for Azure services and lacks some of the Azure-specific optimizations and integrations found in @azure/core-amqp.

rhea

The 'rhea' package is another AMQP 1.0 client library for Node.js. It offers a flexible and extensible API for working with AMQP connections and messaging. Like 'amqp10', it is a general-purpose library and does not include Azure-specific features or optimizations.

amqplib

The 'amqplib' package is a client for the AMQP 0.9.1 protocol, commonly used with RabbitMQ. While it provides robust support for AMQP messaging, it is not compatible with AMQP 1.0 and therefore not suitable for use with Azure services that require AMQP 1.0.

README

Azure Core AMQP client library for JavaScript

The @azure/core-amqp package provides common functionality for Azure JavaScript libraries that use the AMQP protocol like the ones for Azure Service Bus and Azure Event Hubs.

Getting started

Installation

Install this library using npm as follows:

npm install @azure/core-amqp

Currently supported environments

• LTS versions of Node.js
• Latest versions of Safari, Chrome, Edge, and Firefox.

See our support policy for more details.

Key concepts

Some of the key features of Azure Core AMQP library are:

• Claims based Authorization
• Request-Response link for sending request and receiving response over AMQP
• Error translation of AMQP error codes along with errors specific to Azure Service Bus and Azure Event Hubs.
• RetryPolicy for retrying a given operation if a retryable error was encountered.

Next steps

You can build and run the tests locally by executing rushx test. Explore the test folder to see advanced usage and behavior of the public classes.

Troubleshooting

The core-amqp library depends on the rhea-promise library for managing connections, and for sending and receiving events over the AMQP protocol.

Logging

You can set the AZURE_LOG_LEVEL environment variable to one of the following values to enable logging to stderr:

• verbose
• info
• warning
• error

You can also set the log level programmatically by importing the @azure/logger package and calling the setLogLevel function with one of the log level values. For example, when you set the log level to info, the logs that are written for levels warning and error are also emitted. This SDK follows the Azure SDK for TypeScript guidelines when determining which level to log to.

When setting a log level either programmatically or via the AZURE_LOG_LEVEL environment variable, any logs that are written using a log level equal to or less than the one you choose will be emitted.

You can alternatively set the DEBUG environment variable to get logs when using this library. This can be useful if you also want to emit logs from the dependencies rhea-promise and rhea as well.

Note: AZURE_LOG_LEVEL, if set, takes precedence over DEBUG. Do not specify any azure libraries via DEBUG when also specifying AZURE_LOG_LEVEL or calling setLogLevel.

• Getting only info level debug logs from the core-amqp library.

export DEBUG=azure:core-amqp:info

• Getting debug logs from the core-amqp and the protocol level library.

export DEBUG=azure:core-amqp:*,rhea*

• If you are not interested in viewing the raw event data (which consumes a large amount of console/disk space) then you can set the DEBUG environment variable as follows:

export DEBUG=azure:core-amqp:*,rhea*,-rhea:raw,-rhea:message

• If you are interested only in errors and SDK warnings, then you can set the DEBUG environment variable as follows:

export DEBUG=azure:core-amqp:(error|warning),rhea-promise:error,rhea:events,rhea:frames,rhea:io,rhea:flow

Logging to a file

• Set the DEBUG environment variable as shown above and then run your test script as follows:
  • Logging statements from you test script go to out.log and logging statement from the sdk go to debug.log.

    node your-test-script.js > out.log 2>debug.log
    

  • Logging statements from your test script and the sdk go to the same file out.log by redirecting stderr to stdout (&1), and then redirect stdout to a file:

    node your-test-script.js >out.log 2>&1
    

  • Logging statements from your test script and the sdk go to the same file out.log.

    node your-test-script.js &> out.log
    

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

If you'd like to contribute to this library, please read the contributing guide to learn more about how to build and test the code.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact [e-mail] with any additional questions or comments.