00f_Why_Git

Getting Started.

Git is great.    Git is good.    Git is powerful.

Alas, that makes it a little daunting getting started.   This document should
help make it a little less painful.  Git is powerful and hopefully you will
find it is worth the effort.

This document is written assuming that you will be using github to contribute
to the TinyProd TinyOS repository structure.


Contents:

- Why Git?
- GitHub
- Set up Git
- Set up your working repository
- Further Reading
- Guidelines


* Why Git?

The main reason behind the selection of GIT is it's fully distributed nature,
fast branching, and associated merge magic.  The TinyOS development community
is essentially world wide and we want to make encourage the rate of development
by making the contribution process very easy as well as accessable.

  o Fully distributed.

  o Everything is local.   No need of a centralized server for anything.
    (note our workflow does require integration repositories but this isn't
    implicit in GIT), nor does it impact the contribution process.

  o Cheap local branching.  This is important.  We want to foster faster
    development.  Try something out while still staying in touch with what
    is happening in the mainline.  This is much more difficult with rTinyOS's
    (research TinyOS) CVS contrib and SVN based repositories.

    Note, branching in GIT is fundamentally different than pretty much any
    other SCM system and is responsbile for much of the productivity of projects
    using GIT.

  o GITHUB.  When coupled with github, git provides very powerful visibility tools
    (what is being changed and by whom).  Code review becomes very easy when
    using GIT and github.

  o Git is Small

  o Git is Fast

  o Support for any workflow.  Although we are using the Integration Manager
    Workflow and core Lead Developer model for the development tree.

  o Allows gradual reintegration of currently active contrib source bodies.
    Currently the contrib source body is maintained in CVS and is rather
    cumbersome to use.

  o Other DVCS could also have been chosen (SVN is not a DVCS), such as Hg
    or Bzr but I happened to be a fan of GIT.   And it seems to be working
    well for what we are trying to do.

    Git is explicitly designed for fully distributed version control.   It
    is currently in use by many major open source projects including Git itself
    and the Linux Kernel.