git support

static/upload.py

 #!/usr/bin/env python
 #
 # Copyright 2007 Google Inc.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Tool for uploading subversion diffs to the codereview app.
+"""Tool for uploading diffs from a version control system to the codereview app.
 
-Usage summary: upload.py [options] [-- svn_diff_options]
+Usage summary: upload.py [options] [-- diff_options]
+
+Diff options are passed to the diff command of the underlying system.
+
+Supported version control systems:
+  Git
+  Subversion
+
+(It is important for Git users to specify a tree-ish to diff against.)
 """
 # This code is derived from appcfg.py in the App Engine SDK (open source),
 # and from ASPN recipe #146306.
 
 import cookielib
 import getpass
 import logging
 import md5
 import mimetypes
 import optparse
 import os
 import re
 import socket
+import subprocess
 import sys
 import urllib
 import urllib2
 import urlparse
 
 try:
   import readline
 except ImportError:
   pass
 
@@ skipping 292 matching lines @@
         os.close(fd)
       # Always chmod the cookie file
       os.chmod(self.cookie_file, 0600)
     else:
       # Don't save cookies across runs of update.py.
       self.cookie_jar = cookielib.CookieJar()
     opener.add_handler(urllib2.HTTPCookieProcessor(self.cookie_jar))
     return opener
 
 
-parser = optparse.OptionParser(usage="%prog [options] [-- svn_diff_options]")
+parser = optparse.OptionParser(usage="%prog [options] [-- diff_options]")
 parser.add_option("-y", "--assume_yes", action="store_true",
                   dest="assume_yes", default=False,
                   help="Assume that the answer to yes/no questions is 'yes'.")
 # Logging
 group = parser.add_option_group("Logging options")
 group.add_option("-q", "--quiet", action="store_const", const=0,
                  dest="verbose", help="Print errors only.")
 group.add_option("-v", "--verbose", action="store_const", const=2,
                  dest="verbose", default=1,
                  help="Print info level logs (default).")
@@ skipping 350 matching lines @@
       else:
         content = RunShell("svn cat", [filename])
       keywords = RunShell("svn -rBASE propget svn:keywords", [filename],
                           silent_ok=True)
       if keywords:
         content = self._CollapseKeywords(content, keywords)
     else:
       StatusUpdate("svn status returned unexpected output: %s" % status)
       sys.exit(False)
     return content, status[0:5]
+
+
+class GitVCS(VersionControlSystem):
+  """Implementation of the VersionControlSystem interface for Git."""
+
+  def __init__(self):
+    # Map of filename -> hash of base file.
+    self.base_hashes = {}
+
+  def GenerateDiff(self, extra_args):
+    # This is more complicated than svn's GenerateDiff because we must convert
+    # the diff output to include an svn-style "Index:" line as well as record
+    # the hashes of the base files, so we can upload them along with our diff.
+    gitdiff = RunShell("git diff", ["--full-index"] + extra_args)
+    svndiff = []
+    filecount = 0
+    filename = None
+    for line in gitdiff.splitlines():
+      match = re.match(r"diff --git a/(.*) b/.*$", line)
+      if match:
+        filecount += 1
+        filename = match.group(1)
+        svndiff.append("Index: %s\n" % filename)
+      else:
+        # The "index" line in a git diff looks like this (long hashes elided):
+        #   index 82c0d44..b2cee3f 100755
+        # We want to save the left hash, as that identifies the base file.
+        match = re.match(r"index (\w+)\.\.", line)
+        if match:
+          self.base_hashes[filename] = match.group(1)
+      svndiff.append(line + "\n")
+    if not filecount:
+      ErrorExit("No valid patches found in output from git diff")
+    return "".join(svndiff)
+
+  def GetUnknownFiles(self):
+    status = RunShell("git ls-files --others", silent_ok=True)
+    return status.splitlines()
+
+  def GetBaseFile(self, filename):
+    hash = self.base_hashes[filename]
+    if hash == "0" * 40:  # All-zero hash indicates no base file.
+      return ("", "A")
+    else:
+      return (RunShell("git show", [hash]), "M")
 
 
 # NOTE: this function is duplicated in engine.py, keep them in sync.
 def SplitPatch(data):
   """Splits a patch into separate pieces for each file.
 
   Args:
     data: A string containing the output of svn diff.
 
   Returns:
@@ skipping 53 matching lines @@
     lines = response_body.splitlines()
     if not lines or lines[0] != "OK":
       StatusUpdate("  --> %s" % response_body)
       sys.exit(False)
     rv.append([lines[1], patch[0]])
   return rv
 
 
 def GuessVCS():
   """Helper to guess the version control system.
+
+  This examines the current directory, guesses which VersionControlSystem
+  we're using, and returns an instance of the appropriate class.  Exit with an
+  error if we can't figure it out.

[Andi Albrecht, 2008/08/19 19:48:34]

Thanks for adding some more docstrings and comments!

 
   Returns:
     A VersionControlSystem instance. Exits if the VCS can't be guessed.
   """
+  # Subversion has a .svn in all working directories.
   if os.path.isdir('.svn'):
     logging.info("Guessed VCS = Subversion")
     return SubversionVCS()
+
+  # Git has a command to test if you're in a git tree.
+  # Try running it, but don't die if we don't have git installed.
+  try:
+    subproc = subprocess.Popen(["git", "rev-parse", "--is-inside-work-tree"],
+                               stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    if subproc.wait() == 0:
+      return GitVCS()
+  except OSError, (errno, message):
+    if errno != 2:  # ENOENT -- they don't have git installed.
+      raise
+
   ErrorExit(("Could not guess version control system. "
              "Are you in a working copy directory?"))
 
 
 def RealMain(argv, data=None):
   logging.basicConfig(format=("%(asctime).19s %(levelname)s %(filename)s:"
                               "%(lineno)s %(message)s "))
   os.environ['LC_ALL'] = 'C'
   options, args = parser.parse_args(argv[1:])
   global verbosity
   verbosity = options.verbose
   if verbosity >= 3:
     logging.getLogger().setLevel(logging.DEBUG)
   elif verbosity >= 2:
     logging.getLogger().setLevel(logging.INFO)
   vcs = GuessVCS()
   if isinstance(vcs, SubversionVCS):
     # base field is only allowed for Subversion.
     # Note: Fetching base files may become deprecated in future releases.
     base = vcs.GuessBase(not options.local_base)
   else:
     base = None
   if not base and not options.local_base:
     # TODO(andi): Enable local_base for other VCS by default.
     # For future use. SubversionVCS.GuessBase() already checks this

[Andi Albrecht, 2008/08/19 19:48:34]

I think we can enable local_base here now for all other VCS. In my current
Bazaar patch this part is:

if not base and not options.local_base:
  options.local_base = True
  logging.info("Enabled upload of base file")

     # condition.
     ErrorExit("Use '--local_base' to upload base files.")
   if not options.assume_yes:
     vcs.CheckForUnknownFiles()
   if not data:
     data = vcs.GenerateDiff(args)
   if verbosity >= 1:
     print "Upload server:", options.server, "(change with -s/--server)"
   if options.issue:
     prompt = "Message describing this patch set: "
@@ skipping 75 matching lines @@
   try:
     RealMain(sys.argv)
   except KeyboardInterrupt:
     print
     StatusUpdate("Interrupted.")
     sys.exit(1)
 
 
 if __name__ == "__main__":
   main()