Development process

[Gustavo Niemeyer]

Hello Stormers,

The way we develop Storm (and other projects as well, for that
matter) allows people to start contributing fairly easily.  I'm
going to give an overview on the procedure so that anyone
interested can jump in and contribute more closely (patches are
still welcome), or at least understand what's going on in
certain situations (e.g. when you see review or review requests
flying somewhere).

Right now, the following people have write access to the
development trunk (AKA are member of the Storm team in
Launchpad):

 - Chris Armstrong (radix)
 - Gustavo Niemeyer (niemeyer)
 - James Henstridge (jamesh)
 - Jamu Kakar (jkakar)
 - Kevin McDermott (bigkevmcd)
 - Michel Pelletier (michelp)

There are no upfront constraints about getting people into
that list, being just a matter of interest and track record.

On the other hand, there's little benefit in being in that
list, since Storm uses Bazaar for version controlling, which
allows anyone to push branches which will even be seen
associated with the Storm project at Launchpad (without any
human intervention), and that's pretty much what people on
this list have to do to get non-trivial features merged
(including myself, of course).

So, to illustrate how's the process of developing a feature
and doing code reviews, let's say that Jolson wants to
contribute a new backend to make Storm "communicate" with DBF
files. Here's a possible story about that,

- Jolson gets excited about a new file format he's just
  discovered: DBF.

- Jolson creates a local branch based on Storm's trunk, using
  the following command:

  bzr branch https://launchpad.net/storm dbf-support

  This will create a local branch named "dbf-support".

- After that, Jolson starts hacking wildly into the branch,
  using TDD to make sure that all changes are properly
  tested, and committing often to create a good track of
  what's going on.

- Excellent. Jolson is happy. He has the feature he wants,
  and life is a joy.  Time to publish his branch:

  bzr push sftp://jolson@launchpad.net/~jolson/storm/dbf-support

  To do that, the only thing Jolson needs is an account in
  Launchpad and an SSH key registered, which he has.  This
  command will associate the branch with his user in Launchpad,
  and with the project.

- Jolson goes to https://bugs.launchpad.net/storm, and
  files a new bug: "Storm is nothing without DBF", explaining
  to whoever reads the ticket how DBF support is a life-critical
  feature in Storm.

- Finally, Jolson associates the branch he developed with the
  bug just opened by clicking on "Add branch" in the left
  navigation tab of the bug page.

- At this point Jolson is mostly done, except for one thing:
  non-trivial features are reviewed by two other developers
  before being merged on the trunk.  So Michel and Jamu grab
  the branch, and look carefully about what was done.  They point
  out some very minor problems and, understanding how important
  the feature is for Storm, they approve the branch otherwise.

- Jolson fixes the minor points mentioned, and push the branch
  to the same place with the latest changes, adding a comment
  afterwards to let everyone know that the branch is available.

- Kevin grabs the branch, and merges into trunk.

- Profit!

That's basically it.  There are variations on details, of
course.  We're not *too* rigid about where the review happens,
for instance (sometimes via mail, or interactively on more
tricky issues), but we do try to follow more or less the same
logic for every change.

-- 
Gustavo Niemeyer
http://niemeyer.net