For internal use or for those programming around the Gmail API.
Returns a token pre-processed with httr::config()
. Most users
do not need to handle tokens "by hand" or, even if they need some
control, gm_auth()
is what they need. If there is no current
token, gm_auth()
is called to either load from cache or
initiate OAuth2.0 flow.
If auth has been deactivated via gm_deauth()
, gm_token()
returns NULL
.