Azure OAuth 2.0 token classes, with an interface based on the Token2.0 class in httr. Rather than calling the initialization methods directly, tokens should be created via get_azure_token().
An R6 object representing an Azure Active Directory token and its associated credentials. AzureToken is the base class, and the others inherit from it.
refresh: Refreshes the token. For expired tokens without an associated refresh token, refreshing really means requesting a new token.
validate: Checks if the token has not yet expired. Note that a token may be invalid for reasons other than having expired, eg if it is revoked on the server.
hash: Computes an MD5 hash on the input fields of the object. Used internally for identification purposes when caching.
cache: Stores the token on disk for use in future sessions.