Wizard is the new autoinstaller management system for
scripts.mit.edu.  It resides on not-backward.mit.edu at:

    /wizard

Developers, read on:

== Compatibility ==

This is Python 2.6 only!

== Module overview ==

- deploy: object model for autoinstall deployments, applications
    and versions

- shell: subprocess wrapper that does logging, error handling
    and asynchronous processing

- sset: "serialized set", use in a mass* command for tracking
    what installs have already been seen and successfully processed

- util: miscellaneous utility functions, right now mostly one-off
    parsing and convenience wrappers

== 'command' package ==

To add a new command to wizard, you need to touch the following
locations:

- bin/wizard
    Add a line describing your command in the helpstring

- wizard/command/commandname.py
    Implement your command there as main(). Copy the function
    signature and scaffolding from another file; it's non-trivial

As a command file, you're expected to have a main() and parse_args()
function.  Try to keep main() one to two page function that can
be browsed for a descriptive overview of what the command does
internally.  Use helper functions liberally.  Place all error classes
at the bottom.

== 'app' package ==

There is a certain amount of application specific code that
needs to be written for each autoinstaller.  These go here.

== Notes when fiddling with application repositories ==

- 'git rebase -p -i' is your friend.  Use it to rewrite history!

- The obvious scripts specific change that a new repository
  will have are the patches, but you should also check the
  autoinstall scripts if they do anything special.  In particular:

    - If it's a PHP application, it's probably inserting a php.ini
      file and creating symlinks to it.  Be sure to replace the
      appropriate values with placeholders WIZARD_SESSIONNAME
      and WIZARD_TMPDIR

    - You will probably need to generate relevant configuration
      files for each version

== Design decisions ==

- A mass tool will plow ahead even if the subcommand throws
  Wizard errors.  Normal errors will cause us to halt
  completely.  If the error that occured is within the realm
  of possibly, and should be dealt with by manual intervention
  (or even possibly a code change), and would not cause harm
  if we continued going, we will keep going, and let the maintainer
  deal later on with the errors en masse.

- We use the Google Python style guide.  See:
    http://code.google.com/p/soc/wiki/PythonStyleGuide
  However, we use 4-space indents, not 2-space indents.