Function App to Function App Authentication always unauthrised

Question

so I have a function (func1) which is AuthorizationLevel.Anonymous which when called along with other things calls another func (func2) with AuthorizationLevel.Func.

On func2 i have gone into the Authentication tab and set an AAD connection, and used the scope and DefaultAzureCredentials to get the token which works.

But it doesn't authenticate successfully.

Any suggestions would be appriciated

Answer 1

Function based authentication uses keys to authenticate, these are strings and can be created/rotated at the function level. If your calling app isn't providing these keys, authentication will fail and you should move it to Anonymous authentication at the function level and instead rely on the User Authentication provided at the Function App level..

https://learn.microsoft.com/en-us/azure/azure-functions/functions-identity-based-connections-tutorial