Quickstart: Use Azure Cache for Redis in Python

In this Quickstart, you incorporate Azure Cache for Redis into a Python script to have access to a secure, dedicated cache that is accessible from any application within Azure.

Skip to the code on GitHub

If you want to skip straight to the code, see the Python quickstart on GitHub.

Prerequisites

• Azure subscription - create one for free
• Python 3
  • For macOS or Linux, download from python.org.
  • For Windows 11, use the Windows Store.

Create an Azure Cache for Redis instance

1. To create a cache, sign in to the Azure portal and select Create a resource.

   

2. On the Get Started page, type Azure Cache for Redis in the search box. Then, select Create.

   

3. On the New Redis Cache page, configure the settings for your cache.

   Setting	Choose a value	Description
   Subscription	Drop down and select your subscription.	The subscription under which to create this new Azure Cache for Redis instance.
   Resource group	Drop down and select a resource group, or select Create new and enter a new resource group name.	Name for the resource group in which to create your cache and other resources. By putting all your app resources in one resource group, you can easily manage or delete them together.
   DNS name	Enter a unique name.	The cache name must be a string between 1 and 63 characters that contain only numbers, letters, or hyphens. The name must start and end with a number or letter, and can't contain consecutive hyphens. Your cache instance's host name is <DNS name>.redis.cache.windows.net.
   Location	Drop down and select a location.	Select a region near other services that use your cache.
   Cache SKU	Drop down and select a SKU.	The SKU determines the size, performance, and features parameters that are available for the cache. For more information, see Azure Cache for Redis Overview.
   Cache size	Drop down and select a size of your cache	For more information, see Azure Cache for Redis Overview.

4. Select the Networking tab or select the Networking button at the bottom of the page.

5. In the Networking tab, select your connectivity method.

6. Select the Next: Advanced tab or select the Next: Advanced button on the bottom of the page to see the Advanced tab.

   

   • For Basic or Standard caches, toggle the selection for a non-TLS port. You can also select if you want to enable Microsoft Entra Authentication.
   • For a Premium cache, configure the settings for non-TLS port, clustering, managed identity, and data persistence. You can also select if you want to enable Microsoft Entra Authentication.

   Important

   For optimal security, Microsoft recommends using Microsoft Entra ID with managed identities to authorize requests against your cache whenever possible. Authorization with Microsoft Entra ID and managed identities provides superior security and ease of use over Shared Key authorization. For more about using managed identities with your caches, see Use Microsoft Entra ID for cache authentication.

7. Select the Next: Tags tab or select the Next: Tags button at the bottom of the page.

8. Optionally, in the Tags tab, enter the name and value if you wish to categorize the resource.

9. Select Review + create. You're taken to the Review + create tab where Azure validates your configuration.

10. After the green Validation passed message appears, select Create.

It takes a while for a cache to create. You can monitor progress on the Azure Cache for Redis Overview page. When Status shows as Running, the cache is ready to use.

Install redis-py library

Redis-py is a Python interface to Azure Cache for Redis. Use the Python packages tool, pip, to install the redis-py package from a command prompt.

The following example used pip3 for Python 3 to install redis-py on Windows 11 from an Administrator command prompt.

Create a Python script to access your cache

Create a Python script to that uses either Microsoft Entra ID or access keys to connect to an Azure Cache for Redis. We recommend you use Microsoft Entra ID.

Microsoft Entra ID Authentication (recommended)

Enable Microsoft Entra ID authentication on your cache

If you have a cache already, you first want to check to see if Microsoft Entra Authentication has been enabled. If not, then enable it. We recommend using Microsoft Entra ID for your applications.

1. In the Azure portal, select the Azure Cache for Redis instance where you'd like to use Microsoft Entra token-based authentication.

2. Select Authentication from the Resource menu.

3. Check in the working pane to see if Enable Microsoft Entra Authentication is checked. If so, you can move on.

4. Select Enable Microsoft Entra Authentication, and enter the name of a valid user. The user you enter is automatically assigned Data Owner Access Policy by default when you select Save. You can also enter a managed identity or service principal to connect to your cache instance.

   

5. A popup dialog box displays asking if you want to update your configuration, and informing you that it takes several minutes. Select Yes.

   Important

   Once the enable operation is complete, the nodes in your cache instance reboots to load the new configuration. We recommend performing this operation during your maintenance window or outside your peak business hours. The operation can take up to 30 minutes.

For information on using Microsoft Entra ID with Azure CLI, see the references pages for identity.

Install the Microsoft Authentication Library

1. Install the Microsoft Authentication Library (MSAL). This library allows you to acquire security tokens from Microsoft identity to authenticate users.

2. You can use the Python Azure identity client library available that uses MSAL to provide token authentication support. Install this library using pip:

pip install azure-identity

Create a Python script using Microsoft Entra ID

1. Create a new text file, add the following script, and save the file as PythonApplication1.py.

2. Replace <Your Host Name> with the value from your Azure Cache for Redis instance. Your host name is of the form <DNS name>.redis.cache.windows.net.

3. Replace <Your Username> with the values from your Microsoft Entra ID user.

   import redis
   from azure.identity import DefaultAzureCredential
   
   scope = "https://redis.azure.com/.default"
   host = "<Your Host Name>"
   port = 6380
   user_name = "<Your Username>"
   
   
   def hello_world():
       cred = DefaultAzureCredential()
       token = cred.get_token(scope)
       r = redis.Redis(host=host,
                       port=port,
                       ssl=True,    # ssl connection is required.
                       username=user_name,
                       password=token.token,
                       decode_responses=True)
       result = r.ping()
       print("Ping returned : " + str(result))
   
       result = r.set("Message", "Hello!, The cache is working with Python!")
       print("SET Message returned : " + str(result))
   
       result = r.get("Message")
       print("GET Message returned : " + result)
   
       result = r.client_list()
       print("CLIENT LIST returned : ")
       for c in result:
           print(f"id : {c['id']}, addr : {c['addr']}")
   
   if __name__ == '__main__':
       hello_world()
   

4. Before you run your Python code from a Terminal, make sure you authorize the terminal for using Microsoft Entra ID.

   azd auth login

5. Run PythonApplication1.py with Python. You should see results like the following example:

   

Create a Python script using reauthentication

Microsoft Entra ID access tokens have limited lifespans, averaging 75 minutes. In order to maintain a connection to your cache, you need to refresh the token. This example demonstrates how to do this using Python.

1. Create a new text file, add the following script. Then, save the file as PythonApplication2.py.

2. Replace <Your Host Name> with the value from your Azure Cache for Redis instance. Your host name is of the form <DNS name>.redis.cache.windows.net.

3. Replace <Your Username> with the values from your Microsoft Entra ID user.

   import time
   import logging
   import redis
   from azure.identity import DefaultAzureCredential
   
   scope = "https://redis.azure.com/.default"
   host = "<Your Host Name>"
   port = 6380
   user_name = "<Your Username>"
   
   def re_authentication():
       _LOGGER = logging.getLogger(__name__)
       cred = DefaultAzureCredential()
       token = cred.get_token(scope)
       r = redis.Redis(host=host,
                       port=port,
                       ssl=True,   # ssl connection is required.
                       username=user_name,
                       password=token.token,
                       decode_responses=True)
       max_retry = 3
       for index in range(max_retry):
           try:
               if _need_refreshing(token):
                   _LOGGER.info("Refreshing token...")
                   tmp_token = cred.get_token(scope)
                   if tmp_token:
                       token = tmp_token
                   r.execute_command("AUTH", user_name, token.token)
               result = r.ping()
               print("Ping returned : " + str(result))
   
               result = r.set("Message", "Hello!, The cache is working with Python!")
               print("SET Message returned : " + str(result))
   
               result = r.get("Message")
               print("GET Message returned : " + result)
   
               result = r.client_list()
               print("CLIENT LIST returned : ")
               for c in result:
                   print(f"id : {c['id']}, addr : {c['addr']}")
               break
           except redis.ConnectionError:
               _LOGGER.info("Connection lost. Reconnecting.")
               token = cred.get_token(scope)
               r = redis.Redis(host=host,
                               port=port,
                               ssl=True,   # ssl connection is required.
                               username=user_name,
                               password=token.token,
                               decode_responses=True)
           except Exception:
               _LOGGER.info("Unknown failures.")
               break
   
   
   def _need_refreshing(token, refresh_offset=300):
       return not token or token.expires_on - time.time() < refresh_offset
   
   if __name__ == '__main__':
       re_authentication()
   

4. Run PythonApplication2.py with Python. You should see results like the following example:

   

   Unlike the first example, If your token expires, this example automatically refreshes it.

Access Key Authentication

Retrieve host name, ports, and access keys from the Azure portal

To connect your Azure Cache for Redis server, the cache client needs the host name, ports, and a key for the cache. Some clients might refer to these items by slightly different names. You can get the host name, ports, and keys from the Azure portal.

• To get the access keys, select Authentication from the Resource menu. Then, select the Access keys tab.

  

• To get the host name and ports for your cache, select Overview from the Resource menu. The host name is of the form <DNS name>.redis.cache.windows.net.

  

Read and write to the cache from the command line

Run Python from the command line to test your cache. First, initiate the Python interpreter in your command line by typing py, and then use the following code. Replace <Your Host Name> and <Your Access Key> with the values from your Azure Cache for Redis instance. Your host name is of the form <DNS name>.redis.cache.windows.net.

>>> import redis
>>> r = redis.Redis(host='<Your Host Name>',
        port=6380, db=0, password='<Your Access Key>', ssl=True)
>>> r.set('foo', 'bar')
True
>>> r.get('foo')
b'bar'

Create a Python script using access keys

Create a new text file, add the following script, and save the file as PythonApplication1.py. Replace <Your Host Name> and <Your Access Key> with the values from your Azure Cache for Redis instance. Your host name is of the form <DNS name>.redis.cache.windows.net.

import redis

myHostname = "<Your Host Name>"
myPassword = "<Your Access Key>"

r = redis.Redis(host=myHostname, port=6380,
                      password=myPassword, ssl=True)

result = r.ping()
print("Ping returned : " + str(result))

result = r.set("Message", "Hello!, The cache is working with Python!")
print("SET Message returned : " + str(result))

result = r.get("Message")
print("GET Message returned : " + result)

result = r.client_list()
print("CLIENT LIST returned : ")
for c in result:
    print(f"id : {c['id']}, addr : {c['addr']}")

Run PythonApplication1.py with Python. You should see results like the following example:

Clean up resources

If you want to continue to use the resources you created in this article, keep the resource group.

Otherwise, if you're finished with the resources, you can delete the Azure resource group that you created to avoid charges.

Important

Deleting a resource group is irreversible. When you delete a resource group, all the resources in it are permanently deleted. Make sure that you do not accidentally delete the wrong resource group or resources. If you created the resources inside an existing resource group that contains resources you want to keep, you can delete each resource individually instead of deleting the resource group.

To delete a resource group

1. Sign in to the Azure portal, and then select Resource groups.

2. Select the resource group you want to delete.

   If there are many resource groups, use the Filter for any field... box, type the name of your resource group you created for this article. Select the resource group in the results list.

   

3. Select Delete resource group.

4. You're asked to confirm the deletion of the resource group. Type the name of your resource group to confirm, and then select Delete.

   

After a few moments, the resource group and all of its resources are deleted.

Related content

• Create a ASP.NET web app that uses an Azure Cache for Redis.