feat: support refresh callable on google.oauth2.credentials.Credentials (#812)
This is an optional parameter that can be set via the constructor.
It is used to provide the credentials with new tokens and their
expiration time on `refresh()` call.
```
def refresh_handler(request, scopes):
# Generate a new token for the requested scopes by calling
# an external process.
return (
"ACCESS_TOKEN",
_helpers.utcnow() + datetime.timedelta(seconds=3600))
creds = google.oauth2.credentials.Credentials(
scopes=scopes,
refresh_handler=refresh_handler)
creds.refresh(request)
```
It is useful in the following cases:
- Useful in general when tokens are obtained by calling some
external process on demand.
- Useful in particular for retrieving downscoped tokens from a
token broker.
This should have no impact on existing behavior. Refresh tokens
will still have higher priority over refresh handlers.
A getter and setter is exposed to make it easy to set the callable
on unpickled credentials as the callable may not be easily serialized.
```
unpickled = pickle.loads(pickle.dumps(oauth_creds))
unpickled.refresh_handler = refresh_handler
```2 files changed
