AccessTokenRetriever is the internal API by which the login module will
retrieve an access token for use in authorization by the broker. The implementation may
involve authentication to a remote system, or it can be as simple as loading the contents
of a file or configuration setting.
Retrieval is a separate concern from validation, so it isn't necessary for
AccessTokenRetriever implementation to validate the integrity of the JWT
retrieveRetrieves a JWT access token in its serialized three-part form. The implementation is free to determine how it should be retrieved but should not perform validation on the result. Note: This is a blocking function and callers should be aware that the implementation may be communicating over a network, with the file system, coordinating threads, etc. The facility in the
LoginModulefrom which this is ultimately called does not provide an asynchronous approach.
nullJWT access token string
IOException- Thrown on errors related to IO during retrieval
closedefault void close() throws IOExceptionLifecycle method to perform a clean shutdown of the retriever. This must be performed by the caller to ensure the correct state, freeing up and releasing any resources performed in