Let’s talk about authentication between Azure Functions and resources used by Azure Functions and conclude with many poorly documented secrets about how to use User Assigned Managed Identity. When we build Azure functions, they usually need to authenticate against other Azure resources: Azure SQL Database, Storage Accounts, Service Bus and many more.
Each of these services have an authentication that we can call “Meh!”: Azure SQL has SQL Standard Logins, storage accounts have SAS tokens, service bus, shared access keys and so on. These are not the safest methods possible. If the key leaks, you will have a security problem because