Create a Python app with the Azure SDK for Python

This document shows examples of how to use the Azure SDK for Python to access your data in Azure App Configuration.

Tip

App Configuration offers a Python provider library that is built on top of the Python SDK and is designed to be easier to use with richer features. It enables configuration settings to be used like a dictionary, and offers other features like configuration composition from multiple labels, key name trimming, and automatic resolution of Key Vault references. Go to the Python quickstart to learn more.

Prerequisites

• Azure subscription - create one for free
• Python 3.8 or later - for information on setting up Python on Windows, see the Python on Windows documentation
• An App Configuration store. Create a store.

Create a key-value

Add the following key-value to the App Configuration store and leave Label and Content Type with their default values. For more information about how to add key-values to a store using the Azure portal or the CLI, go to Create a key-value.

Key	Value
TestApp:Settings:Message	Data from Azure App Configuration

Set up the Python app

1. Create a new directory for the project named app-configuration-example.

   mkdir app-configuration-example
   

2. Switch to the newly created app-configuration-example directory.

   cd app-configuration-example
   

3. Install the Azure App Configuration client library by using the pip install command.

   pip install azure-appconfiguration
   

4. Create a new file called app-configuration-example.py in the app-configuration-example directory and add the following code:

   import os
   from azure.appconfiguration import AzureAppConfigurationClient, ConfigurationSetting
   
   try:
       print("Azure App Configuration - Python example")
       # Example code goes here
   except Exception as ex:
       print('Exception:')
       print(ex)
   

Note

The code snippets in this example will help you get started with the App Configuration client library for Python. For your application, you should also consider handling exceptions according to your needs. To learn more about exception handling, please refer to our Python SDK documentation.

Configure your App Configuration connection string

1. Set an environment variable named AZURE_APPCONFIG_CONNECTION_STRING, and set it to the connection string of your App Configuration store. At the command line, run the following command:

   Windows command prompt

   To run the app locally using the Windows command prompt, run the following command and replace <app-configuration-store-connection-string> with the connection string of your app configuration store:

   setx AZURE_APPCONFIG_CONNECTION_STRING "<connection-string-of-your-app-configuration-store>"
   

   PowerShell

   If you use Windows PowerShell, run the following command and replace <app-configuration-store-connection-string> with the connection string of your app configuration store:

   $Env:AZURE_APPCONFIG_CONNECTION_STRING = "<app-configuration-store-connection-string>"
   

   macOS

   If you use macOS, run the following command and replace <app-configuration-store-connection-string> with the connection string of your app configuration store:

   export AZURE_APPCONFIG_CONNECTION_STRING='<app-configuration-store-connection-string>'
   

   Linux

   If you use Linux, run the following command and replace <app-configuration-store-connection-string> with the connection string of your app configuration store:

   export AZURE_APPCONFIG_CONNECTION_STRING='<app-configuration-store-connection-string>'
   

2. Print out the value of the environment variable to validate that it is set properly with the command below.

   Windows command prompt

   Using the Windows command prompt, restart the command prompt to allow the change to take effect and run the following command:

   echo %AZURE_APPCONFIG_CONNECTION_STRING%
   

   PowerShell

   If you use Windows PowerShell, run the following command:

   $Env:AZURE_APPCONFIG_CONNECTION_STRING
   

   macOS

   If you use macOS, run the following command:

   echo "$AZURE_APPCONFIG_CONNECTION_STRING"
   

   Linux

   If you use Linux, run the following command:

   echo "$AZURE_APPCONFIG_CONNECTION_STRING"
   

Code samples

The sample code snippets in this section show you how to perform common operations with the App Configuration client library for Python. Add these code snippets to the try block in app-configuration-example.py file you created earlier.

Note

The App Configuration client library refers to a key-value object as ConfigurationSetting. Therefore, in this article, the key-values in App Configuration store will be referred to as configuration settings.

Learn below how to:

• Connect to an App Configuration store
• Get a configuration setting
• Add a configuration setting
• Get a list of configuration settings
• Lock a configuration setting
• Unlock a configuration setting
• Update a configuration setting
• Delete a configuration setting

Connect to an App Configuration store

The following code snippet creates an instance of AzureAppConfigurationClient using the connection string stored in your environment variables.

    connection_string = os.getenv('AZURE_APPCONFIG_CONNECTION_STRING')
    app_config_client = AzureAppConfigurationClient.from_connection_string(connection_string)

Get a configuration setting

The following code snippet retrieves a configuration setting by key name.

    retrieved_config_setting = app_config_client.get_configuration_setting(key='TestApp:Settings:Message')
    print("\nRetrieved configuration setting:")
    print("Key: " + retrieved_config_setting.key + ", Value: " + retrieved_config_setting.value)

Add a configuration setting

The following code snippet creates a ConfigurationSetting object with key and value fields and invokes the add_configuration_setting method. This method will throw an exception if you try to add a configuration setting that already exists in your store. If you want to avoid this exception, the set_configuration_setting method can be used instead.

    config_setting = ConfigurationSetting(
        key='TestApp:Settings:NewSetting',
        value='New setting value'
    )
    added_config_setting = app_config_client.add_configuration_setting(config_setting)
    print("\nAdded configuration setting:")
    print("Key: " + added_config_setting.key + ", Value: " + added_config_setting.value)

Get a list of configuration settings

The following code snippet retrieves a list of configuration settings. The key_filter and label_filter arguments can be provided to filter key-values based on key and label respectively. For more information on filtering, see how to query configuration settings.

    filtered_settings_list = app_config_client.list_configuration_settings(key_filter="TestApp*")
    print("\nRetrieved list of configuration settings:")
    for item in filtered_settings_list:
        print("Key: " + item.key + ", Value: " + item.value)

Lock a configuration setting

The lock status of a key-value in App Configuration is denoted by the read_only attribute of the ConfigurationSetting object. If read_only is True, the setting is locked. The set_read_only method can be invoked with read_only=True argument to lock the configuration setting.

    locked_config_setting = app_config_client.set_read_only(added_config_setting, read_only=True)
    print("\nRead-only status for " + locked_config_setting.key + ": " + str(locked_config_setting.read_only))

Unlock a configuration setting

If the read_only attribute of a ConfigurationSetting is False, the setting is unlocked. The set_read_only method can be invoked with read_only=False argument to unlock the configuration setting.

    unlocked_config_setting = app_config_client.set_read_only(locked_config_setting, read_only=False)
    print("\nRead-only status for " + unlocked_config_setting.key + ": " + str(unlocked_config_setting.read_only))

Update a configuration setting

The set_configuration_setting method can be used to update an existing setting or create a new setting. The following code snippet changes the value of an existing configuration setting.

    added_config_setting.value = "Value has been updated!"
    updated_config_setting = app_config_client.set_configuration_setting(added_config_setting)
    print("\nUpdated configuration setting:")
    print("Key: " + updated_config_setting.key + ", Value: " + updated_config_setting.value)

Delete a configuration setting

The following code snippet deletes a configuration setting by key name.

    deleted_config_setting = app_config_client.delete_configuration_setting(key="TestApp:Settings:NewSetting")
    print("\nDeleted configuration setting:")
    print("Key: " + deleted_config_setting.key + ", Value: " + deleted_config_setting.value)

Run the app

In this example, you created a Python app that uses the Azure App Configuration client library to retrieve a configuration setting created through the Azure portal, add a new setting, retrieve a list of existing settings, lock and unlock a setting, update a setting, and finally delete a setting.

At this point, your app-configuration-example.py file should have the following code:

import os
from azure.appconfiguration import AzureAppConfigurationClient, ConfigurationSetting

try:
    print("Azure App Configuration - Python example")
    # Example code goes here

    connection_string = os.getenv('AZURE_APPCONFIG_CONNECTION_STRING')
    app_config_client = AzureAppConfigurationClient.from_connection_string(connection_string)

    retrieved_config_setting = app_config_client.get_configuration_setting(key='TestApp:Settings:Message')
    print("\nRetrieved configuration setting:")
    print("Key: " + retrieved_config_setting.key + ", Value: " + retrieved_config_setting.value)

    config_setting = ConfigurationSetting(
        key='TestApp:Settings:NewSetting',
        value='New setting value'
    )
    added_config_setting = app_config_client.add_configuration_setting(config_setting)
    print("\nAdded configuration setting:")
    print("Key: " + added_config_setting.key + ", Value: " + added_config_setting.value)

    filtered_settings_list = app_config_client.list_configuration_settings(key_filter="TestApp*")
    print("\nRetrieved list of configuration settings:")
    for item in filtered_settings_list:
        print("Key: " + item.key + ", Value: " + item.value)

    locked_config_setting = app_config_client.set_read_only(added_config_setting, read_only=True)
    print("\nRead-only status for " + locked_config_setting.key + ": " + str(locked_config_setting.read_only))

    unlocked_config_setting = app_config_client.set_read_only(locked_config_setting, read_only=False)
    print("\nRead-only status for " + unlocked_config_setting.key + ": " + str(unlocked_config_setting.read_only))

    added_config_setting.value = "Value has been updated!"
    updated_config_setting = app_config_client.set_configuration_setting(added_config_setting)
    print("\nUpdated configuration setting:")
    print("Key: " + updated_config_setting.key + ", Value: " + updated_config_setting.value)

    deleted_config_setting = app_config_client.delete_configuration_setting(key="TestApp:Settings:NewSetting")
    print("\nDeleted configuration setting:")
    print("Key: " + deleted_config_setting.key + ", Value: " + deleted_config_setting.value)

except Exception as ex:
    print('Exception:')
    print(ex)

In your console window, navigate to the directory containing the app-configuration-example.py file and execute the following Python command to run the app:

python app-configuration-example.py

You should see the following output:

Azure App Configuration - Python example

Retrieved configuration setting:
Key: TestApp:Settings:Message, Value: Data from Azure App Configuration

Added configuration setting:
Key: TestApp:Settings:NewSetting, Value: New setting value

Retrieved list of configuration settings:
Key: TestApp:Settings:Message, Value: Data from Azure App Configuration
Key: TestApp:Settings:NewSetting, Value: New setting value

Read-only status for TestApp:Settings:NewSetting: True

Read-only status for TestApp:Settings:NewSetting: False

Updated configuration setting:
Key: TestApp:Settings:NewSetting, Value: Value has been updated!

Deleted configuration setting:
Key: TestApp:Settings:NewSetting, Value: Value has been updated!

Clean up resources

If you don't want to continue using the resources created in this article, delete the resource group you created here to avoid charges.

Important

Deleting a resource group is irreversible. The resource group and all the resources in it are permanently deleted. Ensure that you don't accidentally delete the wrong resource group or resources. If you created the resources for this article inside a resource group that contains other resources you want to keep, delete each resource individually from its respective pane instead of deleting the resource group.

1. Sign in to the Azure portal, and select Resource groups.
2. In the Filter by name box, enter the name of your resource group.
3. In the result list, select the resource group name to see an overview.
4. Select Delete resource group.
5. You're asked to confirm the deletion of the resource group. Enter the name of your resource group to confirm, and select Delete.

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

Next steps

This guide showed you how to use the Azure SDK for Python to access your data in Azure App Configuration.

For additional code samples, visit:

Azure App Configuration client library samples

To learn how to use Azure App Configuration with Python apps, go to:

Create a Python app with Azure App Configuration