tree 12a585b3b32e395b76d4336cc72d7707872cf64a
parent 19e022d8cf43ce81f046bae8cc18c5397cc7732f
author Shin Fan <shinfan@google.com> 1544822591 -0800
committer Jean de Klerk <deklerk@google.com> 1546621657 +0000

Add support for JWT token auth in client options.

- The credentials will default to use JWT token with default audience. If user does not specify anything, JWT token auth is the default method.
- OAuth is used only when scopes are provided
- Providing both scopes and audiences at the same is disallowed.

Change-Id: I69f9d678e4c837d6e03915e3b3b9b8634ea641d7
Reviewed-on: https://code-review.googlesource.com/c/36471
Reviewed-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jean de Klerk <deklerk@google.com>