Prerequisites
This page assumes that you have already:
Configuring authentication
To authenticate with a service account:
- Import the App Engine Endpoints API in your API class: - import endpoints
- Add an issuer object for the service account to the API decorator. For example: - @endpoints.api( name='echo', version='v1', issuers={'serviceAccount': endpoints.Issuer( 'YOUR_SERVICE_ACCOUNT_EMAIL', 'https://www.googleapis.com/robot/v1/metadata/x509/YOUR_SERVICE_ACCOUNT_EMAIL')}, audiences={'serviceAccount': ['YOUR_AUDIENCE']})- Replace echowith the name of your API.
- Replace v1with your API version.
- Replace YOUR_SERVICE_ACCOUNT_EMAILwith your service account email.
- Replace YOUR_AUDIENCEwith the value in theaudfield sent by the calling service.
 
- Replace 
- In each API method where you want to check for proper authentication, check for a valid - Userand raise error- 401if there isn't one, as shown in this sample method definition:- user = endpoints.get_current_user() # If there's no user defined, the request was unauthenticated, so we # raise 401 Unauthorized.
- Deploy the API. You need to redeploy the API whenever you add new clients.