Azure Storage Queues client library for Python

Azure Queue storage is a service for storing large numbers of messages that can be accessed from anywhere in the world via authenticated calls using HTTP or HTTPS. A single queue message can be up to 64 KiB in size, and a queue can contain millions of messages, up to the total capacity limit of a storage account.

Common uses of Queue storage include:

Creating a backlog of work to process asynchronously
Passing messages between different parts of a distributed application

Getting started

Prerequisites

Python 3.9 or later is required to use this package. For more details, please read our page on Azure SDK for Python version support policy.
You must have an Azure subscription and an Azure storage account to use this package.

Install the package

Install the Azure Storage Queues client library for Python with pip:

pip install azure-storage-queue

Create a storage account

If you wish to create a new storage account, you can use the Azure Portal, Azure PowerShell, or Azure CLI:

# Create a new resource group to hold the storage account -
# if using an existing resource group, skip this step
az group create --name my-resource-group --location westus2

# Create the storage account
az storage account create -n my-storage-account-name -g my-resource-group

Create the client

The Azure Storage Queues client library for Python allows you to interact with three types of resources: the storage account itself, queues, and messages. Interaction with these resources starts with an instance of a client. To create a client object, you will need the storage account's queue service endpoint URL and a credential that allows you to access the storage account:

from azure.storage.queue import QueueServiceClient

service = QueueServiceClient(account_url="https://<my-storage-account-name>.queue.core.windows.net/", credential=credential)

Looking up the account URL

You can find the storage account's queue service URL using the Azure Portal, Azure PowerShell, or Azure CLI:

# Get the queue service URL for the storage account
az storage account show -n my-storage-account-name -g my-resource-group --query "primaryEndpoints.queue"

Types of credentials

The credential parameter may be provided in a number of different forms, depending on the type of authorization you wish to use:

To use a shared access signature (SAS) token, provide the token as a string. If your account URL includes the SAS token, omit the credential parameter. You can generate a SAS token from the Azure Portal under "Shared access signature" or use one of the generate_sas() functions to create a sas token for the storage account or queue:

from datetime import datetime, timedelta
from azure.storage.queue import QueueServiceClient, generate_account_sas, ResourceTypes, AccountSasPermissions

sas_token = generate_account_sas(
    account_name="<storage-account-name>",
    account_key="<account-access-key>",
    resource_types=ResourceTypes(service=True),
    permission=AccountSasPermissions(read=True),
    start=datetime.utcnow(),
    expiry=datetime.utcnow() + timedelta(hours=1)
)

queue_service_client = QueueServiceClient(account_url="https://<my_account_name>.queue.core.windows.net", credential=sas_token)

To use a storage account shared key (aka account key or access key), provide the key as a string. This can be found in the Azure Portal under the "Access Keys" section or by running the following Azure CLI command:

az storage account keys list -g MyResourceGroup -n MyStorageAccount

Use the key as the credential parameter to authenticate the client:
```
from azure.storage.queue import QueueServiceClient
service = QueueServiceClient(account_url="https://<my_account_name>.queue.core.windows.net", credential="<account_access_key>")
```
To use an Azure Active Directory (AAD) token credential, provide an instance of the desired credential type obtained from the azure-identity library. For example, DefaultAzureCredential can be used to authenticate the client.

This requires some initial setup:
- Install azure-identity
- Register a new AAD application and give permissions to access Azure Storage
- Grant access to Azure Queue data with RBAC in the Azure Portal
- Set the values of the client ID, tenant ID, and client secret of the AAD application as environment variables: AZURE_TENANT_ID, AZURE_CLIENT_ID, AZURE_CLIENT_SECRET
Use the returned token credential to authenticate the client:
```
from azure.identity import DefaultAzureCredential
from azure.storage.queue import QueueServiceClient
token_credential = DefaultAzureCredential()

queue_service_client = QueueServiceClient(
    account_url="https://<my_account_name>.queue.core.windows.net",
    credential=token_credential
)
```

Creating the client from a connection string

Depending on your use case and authorization method, you may prefer to initialize a client instance with a storage connection string instead of providing the account URL and credential separately. To do this, pass the storage connection string to the client's from_connection_string class method:

from azure.storage.queue import QueueServiceClient

connection_string = "DefaultEndpointsProtocol=https;AccountName=xxxx;AccountKey=xxxx;EndpointSuffix=core.windows.net"
service = QueueServiceClient.from_connection_string(conn_str=connection_string)

The connection string to your storage account can be found in the Azure Portal under the "Access Keys" section or by running the following CLI command:

az storage account show-connection-string -g MyResourceGroup -n MyStorageAccount

Key concepts

The following components make up the Azure Queue Service:

The storage account itself
A queue within the storage account, which contains a set of messages
A message within a queue, in any format, of up to 64 KiB

The Azure Storage Queues client library for Python allows you to interact with each of these components through the use of a dedicated client object.

Async Clients

This library includes a complete async API supported on Python 3.5+. To use it, you must first install an async transport, such as aiohttp. See azure-core documentation for more information.

Async clients and credentials should be closed when they're no longer needed. These objects are async context managers and define async close methods.

Clients

Two different clients are provided to interact with the various components of the Queue Service:

QueueServiceClient - this client represents interaction with the Azure storage account itself, and allows you to acquire preconfigured client instances to access the queues within. It provides operations to retrieve and configure the account properties as well as list, create, and delete queues within the account. To perform operations on a specific queue, retrieve a client using the get_queue_client method.
QueueClient - this client represents interaction with a specific queue (which need not exist yet). It provides operations to create, delete, or configure a queue and includes operations to send, receive, peek, delete, and update messages within it.

Messages

Send - Adds a message to the queue and optionally sets a visibility timeout for the message.

azure-storage-queue

Description