Backing Up Repos

git-backup

#!/usr/bin/env ruby
#
# Copyright (c) 2012 Konstantin Bender.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

# This script pushes (forced) all branches of the repo to a backup repo defined
# in the (global or local) git config file under `backup.url`. Each pushed
# branch is prefixed with the name of the remote repo followed by a slash
# followed by the original branch name.
#
# The main use case is to have a backup either of full private branches
# or commits that are not yet pushed to origin. You need only one private
# backup repo for any number of projects.
#
# INSTALLATION: Put this script somewhere in your path and make it executable
# (chmod +x git-backup).
#
# EXAMPLE: Lets say I'm working on a project called 'milk' and 'sugar' with the
# following origin urls:
#
#     git@github.com:konstantinbe/milk.git
#     git@github.com:konstantinbe/sugar.git
#
# Create a backup repo:
#
#     git@github.com:konstantinbe/backup.git
#
# Configure git for backup:
#
#     git config --global backup.url git@github.com:konstantinbe/backup.git
#
# Now at any time call 'git backup' from within a local repo. In our case:
#
#     cd ~/projects/milk
#     ... do some work ...
#     git backup
#
#     cd ~/projects/sugar
#     ... do some work ...
#     git backup
#
# Each local branch will be prefixed with the repo name and pushed (forced) to
# the backup repo, which in our case might look as follows:
#
#     git ls-remote --heads git@github.com:konstantinbe/backup.git
#
#     423fd3adace9db89b16004745df9150e5e09620e  refs/heads/master
#     32c79ed0f051ab73a9ce863f8f1b447e375814f4  refs/heads/milk/dictionary
#     32c8d8d93883b469d800dfd99369a1400172c1c9  refs/heads/milk/gh-pages
#     717c4623c9591b719a6037edbb8eaaf9381df97a  refs/heads/milk/master
#     e74a68957311c205f7e511fcd277a422061aa21c  refs/heads/sugar/gh-pages
#     e74a68957311c205f7e511fcd277a422061aa21c  refs/heads/sugar/master
#
# ---------------------------------------------------------------- constants ---

OK = "\33[0m\33[32mOK\33[0m"
FAILED = "\33[0m\33[31mFAILED\33[0m"

ORIGIN = `git config remote.origin.url`.chomp
BACKUP = `git config backup.url`.chomp
PREFIX = ORIGIN.scan(/\/(.*)\.git/).first.first.to_s

# ---------------------------------------------------------------- functions ---

def check(condition)
  unless condition
    puts FAILED
    exit 1
  end
end

def run(command)
  success = system command
  check success
end

def put(string)
  print string
  STDOUT.flush
end

# ------------------------------------------------------------------- script ---

refspecs = `git branch`.chomp.map do |branch|
  name = branch.scan(/\S+$/).first.first.to_s
  "#{name}:#{PREFIX}/#{name}"
end

put "Backing up #{refspecs.length} branch(es) ... "
run "git push --quiet --force #{BACKUP} #{refspecs.join ' '}"
puts OK