ADAL to MSAL migration guide for Python
This article highlights changes you need to make to migrate an app that uses the Azure Active Directory Authentication Library (ADAL) to use the Microsoft Authentication Library (MSAL).
You can learn more about MSAL and get started with an overview of the Microsoft Authentication Library.
ADAL works with the Azure Active Directory (Azure AD) v1.0 endpoint. The Microsoft Authentication Library (MSAL) works with the Microsoft identity platform--formerly known as the Azure Active Directory v2.0 endpoint. The Microsoft identity platform differs from Azure AD v1.0 in that it:
Work and school accounts (Azure AD provisioned accounts)
Personal accounts (such as Outlook.com or Hotmail.com)
Your customers who bring their own email or social identity (such as LinkedIn, Facebook, Google) via the Azure AD B2C offering
Is standards compatible with:
- OAuth v2.0
- OpenID Connect (OIDC)
For more information about MSAL, see MSAL overview.
Scopes not resources
ADAL Python acquires tokens for resources, but MSAL Python acquires tokens for scopes. The API surface in MSAL Python does not have resource parameter anymore. You would need to provide scopes as a list of strings that declare the desired permissions and resources that are requested. To see some example of scopes, see Microsoft Graph's scopes.
You can add the
/.default scope suffix to the resource to help migrate your apps from the v1.0 endpoint (ADAL) to the Microsoft identity platform (MSAL). For example, for the resource value of
https://graph.microsoft.com, the equivalent scope value is
https://graph.microsoft.com/.default. If the resource is not in the URL form, but a resource ID of the form
XXXXXXXX-XXXX-XXXX-XXXXXXXXXXXX, you can still use the scope value as
For more details about the different types of scopes, refer to Permissions and consent in the Microsoft identity platform and the Scopes for a Web API accepting v1.0 tokens articles.
Azure Active Directory Authentication Library (ADAL) for Python uses the exception
AdalError to indicate that there's been a problem. MSAL for Python typically uses error codes, instead. For more information, see MSAL for Python error handling.
The following table lists an API in ADAL for Python, and the one to use in its place in MSAL for Python:
Migrate existing refresh tokens for MSAL Python
The Microsoft Authentication Library (MSAL) abstracts the concept of refresh tokens. MSAL Python provides an in-memory token cache by default so that you don't need to store, lookup, or update refresh tokens. Users will also see fewer sign-in prompts because refresh tokens can usually be updated without user intervention. For more information about the token cache, see Custom token cache serialization in MSAL for Python.
The following code will help you migrate your refresh tokens managed by another OAuth2 library (including but not limited to ADAL Python) to be managed by MSAL for Python. One reason for migrating those refresh tokens is to prevent existing users from needing to sign in again when you migrate your app to MSAL for Python.
The method for migrating a refresh token is to use MSAL for Python to acquire a new access token using the previous refresh token. When the new refresh token is returned, MSAL for Python will store it in the cache. Since MSAL Python 1.3.0, we provide an API inside MSAL for this purpose. Please refer to the following code snippet, quoted from a completed sample of migrating refresh tokens with MSAL Python
import msal def get_preexisting_rt_and_their_scopes_from_elsewhere(): # Maybe you have an ADAL-powered app like this # https://github.com/AzureAD/azure-activedirectory-library-for-python/blob/1.2.3/sample/device_code_sample.py#L72 # which uses a resource rather than a scope, # you need to convert your v1 resource into v2 scopes # See https://learn.microsoft.com/azure/active-directory/develop/migrate-python-adal-msal#scopes-not-resources # You may be able to append "/.default" to your v1 resource to form a scope # See https://learn.microsoft.com/azure/active-directory/develop/v2-permissions-and-consent#the-default-scope # Or maybe you have an app already talking to the Microsoft identity platform, # powered by some 3rd-party auth library, and persist its tokens somehow. # Either way, you need to extract RTs from there, and return them like this. return [ ("old_rt_1", ["scope1", "scope2"]), ("old_rt_2", ["scope3", "scope4"]), ] # We will migrate all the old RTs into a new app powered by MSAL app = msal.PublicClientApplication( "client_id", authority="...", # token_cache=... # Default cache is in memory only. # You can learn how to use SerializableTokenCache from # https://msal-python.readthedocs.io/en/latest/#msal.SerializableTokenCache ) # We choose a migration strategy of migrating all RTs in one loop for old_rt, scopes in get_preexisting_rt_and_their_scopes_from_elsewhere(): result = app.acquire_token_by_refresh_token(old_rt, scopes) if "error" in result: print("Discarding unsuccessful RT. Error: ", json.dumps(result, indent=2)) print("Migration completed")