Device Code Flow in Azure AD using Python's requests module and MSAL
Sample on how to integrate requests with MSAL to achieve device code flow
If you have created any Python application that required integration with Azure Active Directory you would have most likely used an excellent library from Azure AD team called MSAL for Python. However there is no easy way to integrate it with requests library which is a very popular HTTP library for Python.
I have written a sample application and reusable class to integrate Python requests library with MSAL to get AD token using Device Code Flow. Device Code Flow is typically used in a client side applications such as CLI. Therefore I have also implemented a TokenCache serialization/deserialization logic to persist the token in file system. This is similar to how Azure CLI persists the token in
Feel free to copy and use
rest_service.py in your own project. The files depends upon following PyPI -
DeviceCodeFlowTokenAuth by passing
auth_config object to it.
auth_config must have
- client_id: Azure AD Application ID
- authority: Azure AD authority
- scope: Scope to send while requesting for token
Pass the initialized
RestService will use it to set Authorization token before sending request.
In addition to above, change _DEFAULT_TOKEN_CACHE_DIR in
DeviceCodeFlowTokenAuth to any folder of your choosing where you would like the token to be chached. More details below.
How does it work
DeviceCodeFlowTokenAuth accepts configuration which contains client_id, authority and scope to get access token. It first checks if a valid access token or refresh token is present in cache. The in-memory cache is serialized and stored as a file named token in a folder specified by
_DEFAULT_TOKEN_CACHE_DIR variable in home folder (default ~/.myapp).
The code will try to read the token from the folder above and populate its TokenCache. If valid access token exist it will use it. Otherwise if a valid refresh token exists it will use it to get a fresh access token and save it in the cache. If neither of them are valid it will initiate device code flow to fetch fresh tokens. The device code flow will print the code generated to console.