Redirect URI to send the response from the authorisation request to.
This must either be OAUTH2_REDIRECT_URI_OOB,
OAUTH2_REDIRECT_URI_OOB_AUTO, or a http://localhost
URI with any port number (optionally) specified.
This URI is where the authorisation server will redirect the user after they have completed interacting with the authentication page
(gdata_oauth2_authorizer_build_authentication_uri()). If it is
OAUTH2_REDIRECT_URI_OOB, a page will be returned in the user’s browser with the authorisation code in its title and also embedded
in the page for the user to copy if it is not possible to automatically extract the code from the page title. If it is
OAUTH2_REDIRECT_URI_OOB_AUTO, a similar page will be returned with
the authorisation code in its title, but without displaying the code to the user — the user will simply be asked to close the page. If
it is a localhost URI, the authentication page will redirect to that URI with the authorisation code appended as a code query
parameter. If the user denies the authentication request, the authentication page will redirect to that URI with error=access_denied
appended as a query parameter.
Note that the redirect URI used must match that registered in Google’s Developer Console for your application.
See the reference documentation for details about choosing a redirect URI.