Make module tools/lister.py which lists all files in a directory
tracked by git. This is done because lister.py will be used by other
scripts in the future which have to introspect files in the repository,
like linters, static code checkers, etc.
It's always been the case that in production, Tornado dumps all the
event queues when shut down so that they can be reloaded by the
replacement Tornado process. This never worked in development because
the codepath for auto-reload didn't go through either a signal or
sys.exit (it re-execs the process instead).
This meant that we didn't have a mechanism for testing the event queue
dump/load functionality in the development environment. We fix this
by adding such dumping/loading. However, this breaks the automatic
reloading of open browser windows on a server restart, so we add that
back in by adjusting the special `restart` events to pass a special
`immediate` flag when used in development.
This also has the benefit of removing the "Bad event queue" errors one
would get on every file save induced restart on the Python console.
Apparently it isn't always the case that removal of jquery and the DOM
prevents cleanup_event_queue from being called via the postunload
hook, so add a check to avoid it being double-called.
Previously, the browser might restart a get_events operation even
while it was in the middle of executing a `DELETE /events` query to
cause its event queue to be de-allocated. This was a rare race
condition when we weren't notifying clients when event queues were
de-allocated, but this will become a common case in the next commit.
This is a no-op right now, but we'll want the new structure for the
next commit, and splitting this out makes it a lot easier to read what
is actually changed in the next commit.
This should fix a problem we've been having with errors downloading
the PhantomJS packages from their original hosting service.
Eventually we should move it to an S3 bucket.