How to log on to user mailbox from service using oAuth and MS Graph API
问题 I am adding oAuth authentication support to daemon application. In case of IMAP, application logs on to every mailbox by specifying userID/password. Office365 oAuth access requires application registration and uses Clients Credential Grant flow. In this case, application authenticates with Azure AD once and accesses every mailbox using oAuth token. This authentication flow requires significant changes of existing code base. I would like to access mailbox in logically same way as IMAP (specify