How can I determine a user_id based on an email address in App Engine?

Question

The newest App Engine SDK (1.2.1) has an API call to compute an ID for a user account based on his email address. (The ID remains the same even if the user changes his addr

Answer 1

The current workaround is to create a User object, store it to the datastore, and fetch it again. If the email corresponds to a valid Google account, the User object in the returned entity will have its user_id field populated.