Skip to main content

Overview

Azure Service Bus is a fully managed enterprise message broker with message queues and publish-subscribe topics. The Ballerina ballerinax/asb connector (v3.9.1) provides programmatic access to Azure Service Bus for sending, receiving, and administering messages across queues, topics, and subscriptions, enabling reliable cloud messaging in your Ballerina integration flows.

Key features

  • Send messages to Azure Service Bus queues and topics with the MessageSender client
  • Receive messages from queues and subscriptions with configurable receive modes (PEEK_LOCK, RECEIVE_AND_DELETE)
  • Schedule messages for future delivery and cancel scheduled messages
  • Batch send and receive operations for high-throughput scenarios
  • Message settlement operations: complete, abandon, dead-letter, and defer
  • Full queue, topic, subscription, and rule administration via the Administrator client
  • Event-driven message consumption using Listener and service callbacks (onMessage, onError)
  • Automatic lock renewal and auto-completion for simplified message processing

Actions

Actions are operations you invoke on Azure Service Bus from your integration. Use these actions for sending messages, receiving from queues, managing entities, and more. The ASB connector exposes actions across four clients:

ClientActions
Message SenderSend individual or batch messages, schedule and cancel scheduled messages
Message ReceiverReceive messages, settle (complete/abandon/dead-letter/defer), and renew locks
AdministratorCreate, get, update, delete, and list queues, topics, subscriptions, and rules
CallerSettlement operations (complete, abandon, dead-letter, defer) available within service callbacks

See the Action Reference for the full list of operations, parameters, and sample code for each client.

Triggers

Triggers allow your integration to react to messages arriving on Azure Service Bus queues or subscriptions in real time. The connector uses an asb:Listener that continuously receives messages and dispatches them to your service callbacks automatically; no polling required.

Supported trigger events:

EventCallbackDescription
Message receivedonMessageFired when a message is received from the configured queue or subscription.
Message retrieval erroronErrorFired when an error occurs during message retrieval.

See the Trigger Reference for listener configuration, service callbacks, and the asb:Message payload structure.

Documentation

  • Setup Guide: This guide walks you through creating an Azure Service Bus namespace, a queue or topic, and obtaining the connection string required to use the ASB connector.

  • Action Reference: Full reference for all clients: operations, parameters, return types, and sample code.

  • Trigger Reference: Reference for event-driven integration using the listener and service model.

  • Example: Learn how to build and configure an integration using the Azure Service Bus connector, including connection setup, operation configuration, execution flow, and event-driven trigger setup.

What's next

How to contribute

As an open source project, WSO2 welcomes contributions from the community.

To contribute to the code for this connector, please create a pull request in the following repository.

Check the issue tracker for open issues that interest you. We look forward to receiving your contributions.