You shouldn’t need to do this on App Engine. We scale out but starting up new docker processes, so you shouldn’t need to worry about throng. By default we autoscale, starting with 2 instances and going up to 20 based on load. You don’t need to do anything to take advantage :)
I forgot to include a step where you need to set up the local environment (sorry!). You just need to edit your server.js to read from both the environment AND the local config. app.yaml isn’t read automatically at runtime on your local machine.
Good question. We’re just using the Parse NPM module — this is not a fork or anything. We just wanted to include an easy sample to clone and run. To update to the latest version, you really just need to update package.json. We update our samples fairly frequently to use the latest version of NPM modules though.
MASTER_KEY is a key you choose, and keep private. It’s used to provide administrative access to your app. You can read all about it here: http://blog.parse.com/learn/engineering/parse-security-i-are-you-the-key-master/
App Engine automatically scales by default. It uses anywhere from 2–20 VMs, based on CPU/Memory load. It just kinda works. As far as monitoring — there’s a perf dashboard in the UI that shows a variety of metrics.
On the question about parse-server — I pointed to our demo, which uses parse-server along with app engine…
Sorry about that! I got a little ahead of myself, the code was sitting in a PR. It’s available now: https://github.com/GoogleCloudPlatform/nodejs-docs-samples/tree/master/appengine/parse-server