Azure Storage SDKs

Azure Storage Queues SDK

This document provides guidance on using the Azure Storage Queue SDK for various programming languages. Azure Queues is a service that stores large numbers of messages that can be accessed from anywhere in the world via HTTP or HTTPS.

Core Concepts

• Queues: A set of messages. Each queue is the scope of access control.
• Messages: Data that can be stored in a queue. A message can be up to 64 KB in size.
• Dequeueing: A message is retrieved from a queue and made invisible to other clients for a specified period (visibility timeout).
• Popping: A message is retrieved and immediately deleted from the queue.
• Peek: Retrieve messages without making them invisible.

SDK Overview

The Azure Storage SDKs simplify interactions with Azure Storage services. They provide idiomatic client libraries for common tasks, including queue management, message enqueuing, dequeuing, and deletion.

Supported Languages

• C# / .NET
• Java
• Python
• JavaScript / TypeScript
• Go

Getting Started with the SDK

Installation

The installation process varies by language. Below are common examples:

• Python:

  pip install azure-storage-queue

• JavaScript/TypeScript:

  npm install @azure/storage-queue

• .NET:

  dotnet add package Azure.Storage.Queues

Authentication

You can authenticate with Azure Storage Queues using:

• Connection String: A shared secret that grants access.
• Shared Access Signatures (SAS): Time-limited access tokens with specific permissions.
• Azure Identity: For managed identities or service principals in Azure environments.

Basic Usage Example (Python)

This example demonstrates creating a queue, adding a message, and retrieving it.

from azure.storage.queue import QueueClient
import os

# Replace with your actual connection string
connect_str = os.getenv("AZURE_STORAGE_CONNECTION_STRING")
queue_name = "my-sample-queue"

try:
    # Create a QueueClient
    queue_client = QueueClient.from_connection_string(connect_str, queue_name)

    # Create the queue if it doesn't exist
    queue_client.create_queue()
    print(f"Queue '{queue_name}' created or already exists.")

    # Send a message
    message_content = "Hello, Azure Queues!"
    response = queue_client.send_message(message_content)
    message_id = response["messageid"]
    pop_receipt = response["popreceipt"]
    print(f"Message sent with ID: {message_id}")

    # Receive a message
    messages = queue_client.receive_messages()
    for msg in messages:
        print(f"Received message: {msg.content}")
        # Delete the message after processing
        queue_client.delete_message(msg.message_id, msg.pop_receipt)
        print(f"Message {msg.message_id} deleted.")

except Exception as e:
    print(f"An error occurred: {e}")

                

Advanced Features

• Message Timed Out: Control how long a message remains invisible after being dequeued.
• Message Metadata: Add custom metadata to messages.
• Batch Operations: Efficiently send or delete multiple messages.
• Queue Metrics and Logging: Monitor queue performance and troubleshoot issues.

Best Practices

• Idempotency: Design your message processing logic to be idempotent, as messages may be delivered more than once.
• Visibility Timeout: Set an appropriate visibility timeout to prevent multiple consumers from processing the same message simultaneously.
• Error Handling: Implement robust error handling and retry mechanisms.
• Queue Size: Be mindful of queue size limits and consider partitioning if you expect a very large number of messages.

Resources