This tutorial is an introduction to Google's Appengine and Pub/Sub. It is an example of what a service responding to an event-driven system might look like.

This tutorial builds on the "hello world" Google App Engine tutorial.

1. Walk through the Google Node.js App Engine tutorial

2. Create a Twitter app account

3. Create a topic and subscription.

    gcloud beta pubsub topics create <your-topic-name>
    gcloud beta pubsub subscriptions create <your-subscription-name> \
      --topic <your-topic-name> \
      --push-endpoint \
        https://<your-project-id>.appspot.com/pubsub/push?token=<your-verification-token> \
      --ack-deadline 30
   

1. Modify the initial "hello world" app with app-v1.js. We will add our own Twitter app credentials and it will tweet as we start our app.
2. Walk through the appengine/pubsub tutorial
3. Combine app-v1 and the pubsub tutorial into app-v2.js.