Azure Functions

Queue Trigger Bindings

Azure Functions provides a Queue trigger that allows you to easily create functions that run in response to messages arriving on an Azure Storage Queue or an Azure Service Bus Queue.

How it Works

When a message is added to a configured queue, the Queue trigger automatically invokes your function. The function receives the message content and can perform actions based on it. The trigger handles polling the queue and processing messages.

Supported Queue Types

Configuration

The queue trigger is configured in your function.json file (for JavaScript, Python, etc.) or via attributes/decorators (for C#, Java).

function.json Example (Azure Storage Queue)


{
  "scriptFile": "../run.js",
  "bindings": [
    {
      "name": "myQueueItem",
      "type": "queueTrigger",
      "direction": "in",
      "queueName": "myqueue-items",
      "connection": "AzureWebJobsStorage"
    }
  ]
}

function.json Example (Azure Service Bus Queue)


{
  "scriptFile": "../run.js",
  "bindings": [
    {
      "name": "message",
      "type": "queueTrigger",
      "direction": "in",
      "queueName": "my-servicebus-queue",
      "connection": "ServiceBusConnection"
    }
  ]
}

Key Properties

Property Description Required
name The name of the variable that holds the queue message in your function code. Yes
type Must be queueTrigger. Yes
direction Must be in for a trigger. Yes
queueName The name of the queue to monitor. Yes
connection The name of an app setting that contains the queue connection string. Yes

Processing Messages

When your function is triggered, the message payload is passed to your function based on the name property defined in the binding.

Example: JavaScript Function

This function logs the content of a message from an Azure Storage Queue.


module.exports = async function (context, myQueueItem) {
    context.log('JavaScript queue trigger function processed work item', myQueueItem);
    // You can access the message content via the myQueueItem variable
    // For example, if the message is JSON:
    // const data = JSON.parse(myQueueItem);
    // context.log('Parsed data:', data);
};

Example: C# Function

This example shows a C# function triggered by an Azure Storage Queue message.


using Microsoft.Azure.Functions.Worker;
using Microsoft.Extensions.Logging;

namespace MyCompany.MyFunctions
{
    public class QueueTriggerFunction
    {
        private readonly ILogger _logger;

        public QueueTriggerFunction(ILogger logger)
        {
            _logger = logger;
        }

        [Function("QueueTriggerCSharp")]
        public void Run([QueueTrigger("myqueue-items", Connection = "AzureWebJobsStorage")] string myQueueItem)
        {
            _logger.LogInformation($"C# Queue trigger function processed: {myQueueItem}");
            // Process the message content
        }
    }
}

Message Deletion

By default, the Queue trigger automatically deletes messages from the queue after they have been successfully processed by your function. If your function throws an unhandled exception, the message may be reprocessed (depending on queue configuration and retry policies).

Advanced Scenarios