s3git.py

   1 #!/usr/bin/python
   2 #
   3 # Author: Paul D. Eden <paul@benchline.org>
   4 # Distributed under the terms of the GNU Public License version 2
   5 # Created: 2008-08-04
   6
   7 import os
   8 import sys
   9 import subprocess
  10
  11 def run(cmd):
  12     subprocess.check_call(cmd, shell=True)
  13
  14 def runbool(cmd):
  15     if subprocess.call(cmd, shell=True) == 0:
  16         return True
  17     else:
  18         return False
  19
  20 def output(cmd):
  21      process = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE)
  22      rval = process.communicate()[0]
  23      if process.returncode != 0:
  24          raise Exception, "%s failed" % cmd
  25      return rval
  26
  27 class NotRepoException(Exception): pass
  28
  29 class S3Git(object):
  30     """
  31     Simple script to automate syncing a local git repository
  32     with Amazon S3
  33
  34     The remote local git directory must have the same
  35     name as the remote S3 directory
  36     """
  37     def __init__(self):
  38         home = os.environ["HOME"]
  39         self.git_repo_dir = self._get_repo()
  40         self.shadow_repo_dir = self._setup_shadow_repo()
  41
  42     def _get_repo(self, directory=""):
  43         """
  44         Recursively tries to find the git repo we are in
  45         if any
  46         """
  47         if not directory:
  48             directory = os.path.realpath(os.getcwd())
  49         if directory == "/":
  50             raise NotRepoException, "This directory is not a git repository"
  51         else:
  52             if self._is_git_repo(directory):
  53                 return directory
  54             else:
  55                 return self._get_repo(os.path.dirname(directory))
  56
  57     def _setup_shadow_repo(self):
  58         """
  59         Makes the repo a clone of shadow_dir
  60         if necessary
  61         """
  62         short_name = os.path.basename(self.git_repo_dir)
  63         parent_dir = os.path.dirname(self.git_repo_dir)
  64         shadow_dir = os.path.join(parent_dir, ".%s.s3" % short_name)
  65         if not os.path.exists(shadow_dir):
  66             self._setup_clone(shadow_dir)
  67         return shadow_dir
  68
  69     def _setup_clone(self, shadow_dir):
  70         # make sure this code is right.  It can be destructive
  71         os.chdir("/tmp")
  72         self._backup_repo()
  73         run("cp -a %s %s" % (self.git_repo_dir, shadow_dir))
  74         run("rm -fr %s" % self.git_repo_dir)
  75         run("git clone file://%s %s" % (shadow_dir, self.git_repo_dir))
  76         os.chdir(self.git_repo_dir)
  77
  78     def _backup_repo(self):
  79         backup_dir = self.git_repo_dir + ".bak"
  80         if os.path.exists(backup_dir):
  81             run("rm -fr %s" % backup_dir)
  82         run("cp -a %s %s" % (self.git_repo_dir, backup_dir))
  83
  84     def _is_git_repo(self, directory):
  85         return os.path.exists("%s/.git" % directory)
  86
  87     def _commit_repo(self):
  88         runbool("git status")
  89         ans = raw_input("Commit the changes to git? ")
  90         if ans.lower() == "y":
  91             print "Here's a shell with which to commit."
  92             run("/bin/dash")
  93
  94     def _s3_to_shadow(self):
  95         run("s3cmd --force --delete-removed sync s3://git_repos/%s %s" % (os.path.basename(self.git_repo_dir), self.shadow_repo_dir))
  96
  97     def _shadow_to_s3(self):
  98         run("s3cmd --delete-removed sync %s s3://git_repos/%s" % (self.shadow_repo_dir,
  99             os.path.basename(self.git_repo_dir)))
 100
 101     def pull(self):
 102         self._s3_to_shadow()
 103         run("git pull")
 104
 105     def push(self):
 106         self._commit_repo()
 107         self._s3_to_shadow()
 108         run("git push")
 109         self._shadow_to_s3()
 110
 111     def main(self, args):
 112         cmd = args[0]
 113         if cmd == "push":
 114             self.push()
 115         elif cmd == "pull":
 116             self.pull()
 117         else:
 118             raise Exception, "%s is an invalid command" % cmd
 119
 120 if __name__ == "__main__":
 121     from optparse import OptionParser
 122     parser = OptionParser()
 123     parser.add_option("-v", "--verbose", action="store_true",
 124                       help="run gregariously")
 125     parser.add_option("-q", "--quiet", action="store_true",
 126                       help="run quietly")
 127     (options, args) = parser.parse_args()
 128     if len(args) < 1 or (args[0] not in ("push", "pull")):
 129         parser.error("You must specify one of 'push' or 'pull'")
 130     c = S3Git()
 131     c.main(args)