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Introduction

frankenserver (technically, frankenserver's monster) is a fork of the Google App Engine SDK with modifications required by Khan Academy. It is specifically targeted at the Python SDK running on Mac OS X or Linux. Other App Engine runtimes and operating systems should work normally but are not tested or supported.

frankenserver's biggest advantage over the vanilla SDK is in how it watches the files in your app for changes. It does this much more efficiently by 1) using a native FSEvents-based file watcher on Mac OS X and 2) respecting the skip_files directive in your app.yaml.

Installation

For Khan Academy developers: frankenserver is a subrepo of webapp so there's nothing to install (assuming you've run make deps). Simply run make serve to serve webapp using frankenserver.

For others: Just git clone this repository into a convenient location and set up a symlink or shell alias for running python python/dev_appserver.py with your desired dev_appserver.py flags. To enable the FSEvents-based file watcher on Mac OS X you'll also need to run pip install -r requirements.txt (highly recommended).

Extra credit

• Set up Desmond's Technicolor Yawn to give your request logs some color. (Khan Academy developers: make serve will automatically use this if you have it installed.)

• Khan Academy developers: use multitail to interleave the logs from frankenserver and kake, our build system, in a single terminal window. (You can run tail -f genfiles/kake-server.log from your webapp directory to get kake's log output.)

Dealing with the upstream codebase

The github repo is typically behind the release tarballs, so we update from upstream using the tarballs.

1. Visit https://cloud.google.com/appengine/downloads and download the latest zipfile.
2. Create a new branch: git checkout master && git checkout -b <gae version>
3. Replace the old code with the new: rm -rf *; unzip <zipfile>
4. If the zipfile toplevel is named google_appengine, do mv google_appengine python
5. git add -A .
6. git commit -am 'Pristine copy of <gae version>, without patches applied'
7. (Now comes the hard part: cherry-picking the frankenserver changes from a previous branch.)
8. Run git branch to see what previous versions exist, then run git log <previous version> to see all the frankenserver changes. Stop when you get to the 'Pristine copy of ' log message (or something similar). Note that commit.
9. Do git log --format=%h --no-merges <commit>..<previous version>. Alternately, if you're curious what these commits are, just do git log --oneline --no-merges <commit>..<previous version>. e.g. git log --oneline --no-merges 526771777..1.9.28
10. Starting from the bottom, and preferably one at a time, run git cherry-pick <commit>. Resolve any conflicts you see.
11. Run python/run_tests.py.