Publsher
Subscriber
Subscriber's ID must be uniq!
Subscriber join to Topic.
I gess Subscriber's ID this like Topic/Subscriber_id.
Subscriber's ID must be project uniq.
push & GAE
From sample...
Endpoint URL has query string.
https://{ver}-dot-{pj}.appspot.com/_ah/push-handlers/receive_message?token=hogefuga
push-ed message
push & Functions
message
logMessage: "Post body: {"message":{"data":"44Gv44GE44CA44Gj44Gj772M","attributes":"attributes":{"key":"imaoka","fuga":"hoge"},"message_id":"87814319259086","messageId":"87814319259086","publish_time":"2017-03-16T09:37:37.635Z","publishTime":"2017-03-16T09:37:37.635Z"},"subscription":"projects/articulate-sol-739/subscriptions/subscription-python-articulate-sol-739-imaoka"}"