I have an application to save Azure Active Directory users to SQL Server. For this I am using MSAL authentication to get the users.
But sometimes my access token will get expired and I will get 401 unauthorized error from Graph. So I need to add the logic of validating the expiry in my code itself. I searched a lot but couldn't find a good solution.
Could anybody help me how to achieve this?
The default lifetime of an access token is variable. When issued, an access token's default lifetime is assigned a random value ranging between 60-90 minutes (75 minutes on average). I suggest you save the Refresh token instead and then obtain the access token any time you want to query the users resource.
The reason for that is that the Refresh tokens have a longer lifetime than access tokens. The default lifetime for the tokens is 90 days and they replace themselves with a fresh token upon every use. As such, whenever a refresh token is used to acquire a new access token, a new refresh token is also issued. The Microsoft identity platform doesn't revoke old refresh tokens when used to fetch new access tokens. Securely delete the old refresh token after acquiring a new one. Refresh tokens need to be stored safely like access tokens or application credentials.
More about Refresh token in Microsoft identity platform can be found here - https://docs.microsoft.com/en-us/azure/active-directory/develop/refresh-tokens
