authorizer

An object which implements Authorizer.

This should have previously been authenticated authorized against this service type (and potentially other service types). The service will use the authorizer to add an authorization token to each request it performs.

Your application should call methods on the Authorizer object itself in order to authenticate with the Google accounts service and authorize against this service type. See the documentation for the particular Authorizer implementation being used for more details.

The authorizer for a service can be changed at runtime for a different Authorizer object or null without affecting ongoing requests and operations.

Note that it's only necessary to set an authorizer on the service if your application is going to make requests of the service which require authorization. For example, listing the current most popular videos on YouTube does not require authorization, but uploading a video to YouTube does. It's an unnecessary overhead to require the user to authorize against a service when not strictly required.