Deploying to appspot.com

Code is not automatically deployed to netlog-viewer.appspot.com once committed to the repository. Rather, a release needs to be prepared and deployed manually by an admin of the netlog-viewer appengine project:

Check out a clean copy of catapult/netlog_viewer (master branch).
Run the automated tests, netlog_viewer/bin/run_dev_server_tests, and confirm that (a) tests ran (b) were successful. (See caveat on CONTRIBUTING - headless tests may fail, in which case need to run them in non-headless mode.)
Authenticate with the gcloud command line tool. (Only needs to be done once.)

gcloud auth login

Build the vulcanized version that will be served by appengine.

netlog_viewer_build/build_for_appengine.py

Run the app server locally, load in browser, and do some basic sanity checks loading a net log file. Be sure to shift-reload so you aren't testing an old cached version, and also check that no JavaScript errors were logged to the console.

cd appengine
dev_appserver.py app.yaml

Deploy without making it the default version yet.

gcloud app deploy --no-promote --project netlog-viewer

Load the versioned URL that was printed in previous step, and again do some manual sanity checks.
Send live traffic to the new version using the GCP console.