thirdparty/rietveld/upload.py
changeset 147 cf9f7d81edec
child 148 37505d64e57b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/thirdparty/rietveld/upload.py	Tue Sep 16 01:18:15 2008 +0000
@@ -0,0 +1,993 @@
+#!/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 diffs from a version control system to the codereview app.
+
+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
+
+# The logging verbosity:
+#  0: Errors only.
+#  1: Status messages.
+#  2: Info logs.
+#  3: Debug logs.
+verbosity = 1
+
+# Max size of patch or base file.
+MAX_UPLOAD_SIZE = 900 * 1024
+
+
+def StatusUpdate(msg):
+  """Print a status message to stdout.
+
+  If 'verbosity' is greater than 0, print the message.
+
+  Args:
+    msg: The string to print.
+  """
+  if verbosity > 0:
+    print msg
+
+
+def ErrorExit(msg):
+  """Print an error message to stderr and exit."""
+  print >>sys.stderr, msg
+  sys.exit(1)
+
+
+class ClientLoginError(urllib2.HTTPError):
+  """Raised to indicate there was an error authenticating with ClientLogin."""
+
+  def __init__(self, url, code, msg, headers, args):
+    urllib2.HTTPError.__init__(self, url, code, msg, headers, None)
+    self.args = args
+    self.reason = args["Error"]
+
+
+class AbstractRpcServer(object):
+  """Provides a common interface for a simple RPC server."""
+
+  def __init__(self, host, auth_function, host_override=None, extra_headers={},
+               save_cookies=False):
+    """Creates a new HttpRpcServer.
+
+    Args:
+      host: The host to send requests to.
+      auth_function: A function that takes no arguments and returns an
+        (email, password) tuple when called. Will be called if authentication
+        is required.
+      host_override: The host header to send to the server (defaults to host).
+      extra_headers: A dict of extra headers to append to every request.
+      save_cookies: If True, save the authentication cookies to local disk.
+        If False, use an in-memory cookiejar instead.  Subclasses must
+        implement this functionality.  Defaults to False.
+    """
+    self.host = host
+    self.host_override = host_override
+    self.auth_function = auth_function
+    self.authenticated = False
+    self.extra_headers = extra_headers
+    self.save_cookies = save_cookies
+    self.opener = self._GetOpener()
+    if self.host_override:
+      logging.info("Server: %s; Host: %s", self.host, self.host_override)
+    else:
+      logging.info("Server: %s", self.host)
+
+  def _GetOpener(self):
+    """Returns an OpenerDirector for making HTTP requests.
+
+    Returns:
+      A urllib2.OpenerDirector object.
+    """
+    raise NotImplementedError()
+
+  def _CreateRequest(self, url, data=None):
+    """Creates a new urllib request."""
+    logging.debug("Creating request for: '%s' with payload:\n%s", url, data)
+    req = urllib2.Request(url, data=data)
+    if self.host_override:
+      req.add_header("Host", self.host_override)
+    for key, value in self.extra_headers.iteritems():
+      req.add_header(key, value)
+    return req
+
+  def _GetAuthToken(self, email, password):
+    """Uses ClientLogin to authenticate the user, returning an auth token.
+
+    Args:
+      email:    The user's email address
+      password: The user's password
+
+    Raises:
+      ClientLoginError: If there was an error authenticating with ClientLogin.
+      HTTPError: If there was some other form of HTTP error.
+
+    Returns:
+      The authentication token returned by ClientLogin.
+    """
+    req = self._CreateRequest(
+        url="https://www.google.com/accounts/ClientLogin",
+        data=urllib.urlencode({
+            "Email": email,
+            "Passwd": password,
+            "service": "ah",
+            "source": "rietveld-codereview-upload",
+            "accountType": "GOOGLE",
+        })
+    )
+    try:
+      response = self.opener.open(req)
+      response_body = response.read()
+      response_dict = dict(x.split("=")
+                           for x in response_body.split("\n") if x)
+      return response_dict["Auth"]
+    except urllib2.HTTPError, e:
+      if e.code == 403:
+        body = e.read()
+        response_dict = dict(x.split("=", 1) for x in body.split("\n") if x)
+        raise ClientLoginError(req.get_full_url(), e.code, e.msg,
+                               e.headers, response_dict)
+      else:
+        raise
+
+  def _GetAuthCookie(self, auth_token):
+    """Fetches authentication cookies for an authentication token.
+
+    Args:
+      auth_token: The authentication token returned by ClientLogin.
+
+    Raises:
+      HTTPError: If there was an error fetching the authentication cookies.
+    """
+    # This is a dummy value to allow us to identify when we're successful.
+    continue_location = "http://localhost/"
+    args = {"continue": continue_location, "auth": auth_token}
+    req = self._CreateRequest("http://%s/_ah/login?%s" %
+                              (self.host, urllib.urlencode(args)))
+    try:
+      response = self.opener.open(req)
+    except urllib2.HTTPError, e:
+      response = e
+    if (response.code != 302 or
+        response.info()["location"] != continue_location):
+      raise urllib2.HTTPError(req.get_full_url(), response.code, response.msg,
+                              response.headers, response.fp)
+    self.authenticated = True
+
+  def _Authenticate(self):
+    """Authenticates the user.
+
+    The authentication process works as follows:
+     1) We get a username and password from the user
+     2) We use ClientLogin to obtain an AUTH token for the user
+        (see http://code.google.com/apis/accounts/AuthForInstalledApps.html).
+     3) We pass the auth token to /_ah/login on the server to obtain an
+        authentication cookie. If login was successful, it tries to redirect
+        us to the URL we provided.
+
+    If we attempt to access the upload API without first obtaining an
+    authentication cookie, it returns a 401 response and directs us to
+    authenticate ourselves with ClientLogin.
+    """
+    for i in range(3):
+      credentials = self.auth_function()
+      try:
+        auth_token = self._GetAuthToken(credentials[0], credentials[1])
+      except ClientLoginError, e:
+        if e.reason == "BadAuthentication":
+          print >>sys.stderr, "Invalid username or password."
+          continue
+        if e.reason == "CaptchaRequired":
+          print >>sys.stderr, (
+              "Please go to\n"
+              "https://www.google.com/accounts/DisplayUnlockCaptcha\n"
+              "and verify you are a human.  Then try again.")
+          break
+        if e.reason == "NotVerified":
+          print >>sys.stderr, "Account not verified."
+          break
+        if e.reason == "TermsNotAgreed":
+          print >>sys.stderr, "User has not agreed to TOS."
+          break
+        if e.reason == "AccountDeleted":
+          print >>sys.stderr, "The user account has been deleted."
+          break
+        if e.reason == "AccountDisabled":
+          print >>sys.stderr, "The user account has been disabled."
+          break
+        if e.reason == "ServiceDisabled":
+          print >>sys.stderr, ("The user's access to the service has been "
+                               "disabled.")
+          break
+        if e.reason == "ServiceUnavailable":
+          print >>sys.stderr, "The service is not available; try again later."
+          break
+        raise
+      self._GetAuthCookie(auth_token)
+      return
+
+  def Send(self, request_path, payload=None,
+           content_type="application/octet-stream",
+           timeout=None,
+           **kwargs):
+    """Sends an RPC and returns the response.
+
+    Args:
+      request_path: The path to send the request to, eg /api/appversion/create.
+      payload: The body of the request, or None to send an empty request.
+      content_type: The Content-Type header to use.
+      timeout: timeout in seconds; default None i.e. no timeout.
+        (Note: for large requests on OS X, the timeout doesn't work right.)
+      kwargs: Any keyword arguments are converted into query string parameters.
+
+    Returns:
+      The response body, as a string.
+    """
+    # TODO: Don't require authentication.  Let the server say
+    # whether it is necessary.
+    if not self.authenticated:
+      self._Authenticate()
+
+    old_timeout = socket.getdefaulttimeout()
+    socket.setdefaulttimeout(timeout)
+    try:
+      tries = 0
+      while True:
+        tries += 1
+        args = dict(kwargs)
+        url = "http://%s%s" % (self.host, request_path)
+        if args:
+          url += "?" + urllib.urlencode(args)
+        req = self._CreateRequest(url=url, data=payload)
+        req.add_header("Content-Type", content_type)
+        try:
+          f = self.opener.open(req)
+          response = f.read()
+          f.close()
+          return response
+        except urllib2.HTTPError, e:
+          if tries > 3:
+            raise
+          elif e.code == 401:
+            self._Authenticate()
+##           elif e.code >= 500 and e.code < 600:
+##             # Server Error - try again.
+##             continue
+          else:
+            raise
+    finally:
+      socket.setdefaulttimeout(old_timeout)
+
+
+class HttpRpcServer(AbstractRpcServer):
+  """Provides a simplified RPC-style interface for HTTP requests."""
+
+  def _Authenticate(self):
+    """Save the cookie jar after authentication."""
+    super(HttpRpcServer, self)._Authenticate()
+    if self.save_cookies:
+      StatusUpdate("Saving authentication cookies to %s" % self.cookie_file)
+      self.cookie_jar.save()
+
+  def _GetOpener(self):
+    """Returns an OpenerDirector that supports cookies and ignores redirects.
+
+    Returns:
+      A urllib2.OpenerDirector object.
+    """
+    opener = urllib2.OpenerDirector()
+    opener.add_handler(urllib2.ProxyHandler())
+    opener.add_handler(urllib2.UnknownHandler())
+    opener.add_handler(urllib2.HTTPHandler())
+    opener.add_handler(urllib2.HTTPDefaultErrorHandler())
+    opener.add_handler(urllib2.HTTPSHandler())
+    opener.add_handler(urllib2.HTTPErrorProcessor())
+    if self.save_cookies:
+      self.cookie_file = os.path.expanduser("~/.codereview_upload_cookies")
+      self.cookie_jar = cookielib.MozillaCookieJar(self.cookie_file)
+      if os.path.exists(self.cookie_file):
+        try:
+          self.cookie_jar.load()
+          self.authenticated = True
+          StatusUpdate("Loaded authentication cookies from %s" %
+                       self.cookie_file)
+        except (cookielib.LoadError, IOError):
+          # Failed to load cookies - just ignore them.
+          pass
+      else:
+        # Create an empty cookie file with mode 600
+        fd = os.open(self.cookie_file, os.O_CREAT, 0600)
+        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] [-- 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).")
+group.add_option("--noisy", action="store_const", const=3,
+                 dest="verbose", help="Print all logs.")
+# Review server
+group = parser.add_option_group("Review server options")
+group.add_option("-s", "--server", action="store", dest="server",
+                 default="codereview.appspot.com",
+                 metavar="SERVER",
+                 help=("The server to upload to. The format is host[:port]. "
+                       "Defaults to 'codereview.appspot.com'."))
+group.add_option("-e", "--email", action="store", dest="email",
+                 metavar="EMAIL", default=None,
+                 help="The username to use. Will prompt if omitted.")
+group.add_option("-H", "--host", action="store", dest="host",
+                 metavar="HOST", default=None,
+                 help="Overrides the Host header sent with all RPCs.")
+group.add_option("--no_cookies", action="store_false",
+                 dest="save_cookies", default=True,
+                 help="Do not save authentication cookies to local disk.")
+# Issue
+group = parser.add_option_group("Issue options")
+group.add_option("-d", "--description", action="store", dest="description",
+                 metavar="DESCRIPTION", default=None,
+                 help="Optional description when creating an issue.")
+group.add_option("-f", "--description_file", action="store",
+                 dest="description_file", metavar="DESCRIPTION_FILE",
+                 default=None,
+                 help="Optional path of a file that contains "
+                      "the description when creating an issue.")
+group.add_option("-r", "--reviewers", action="store", dest="reviewers",
+                 metavar="REVIEWERS", default=None,
+                 help="Add reviewers (comma separated email addresses).")
+group.add_option("--cc", action="store", dest="cc",
+                 metavar="CC", default=None,
+                 help="Add CC (comma separated email addresses).")
+# Upload options
+group = parser.add_option_group("Patch options")
+group.add_option("-m", "--message", action="store", dest="message",
+                 metavar="MESSAGE", default=None,
+                 help="A message to identify the patch. "
+                      "Will prompt if omitted.")
+group.add_option("-i", "--issue", type="int", action="store",
+                 metavar="ISSUE", default=None,
+                 help="Issue number to which to add. Defaults to new issue.")
+group.add_option("-l", "--local_base", action="store_true",
+                 dest="local_base", default=False,
+                 help="Base files will be uploaded.")
+group.add_option("--send_mail", action="store_true",
+                 dest="send_mail", default=False,
+                 help="Send notification email to reviewers.")
+
+
+def GetRpcServer(options):
+  """Returns an instance of an AbstractRpcServer.
+
+  Returns:
+    A new AbstractRpcServer, on which RPC calls can be made.
+  """
+
+  rpc_server_class = HttpRpcServer
+
+  def GetUserCredentials():
+    """Prompts the user for a username and password."""
+    email = options.email
+    if email is None:
+      email = raw_input("Email: ").strip()
+    password = getpass.getpass("Password for %s: " % email)
+    return (email, password)
+
+  # If this is the dev_appserver, use fake authentication.
+  host = (options.host or options.server).lower()
+  if host == "localhost" or host.startswith("localhost:"):
+    email = options.email
+    if email is None:
+      email = "test@example.com"
+      logging.info("Using debug user %s.  Override with --email" % email)
+    server = rpc_server_class(
+        options.server,
+        lambda: (email, "password"),
+        host_override=options.host,
+        extra_headers={"Cookie":
+                       'dev_appserver_login="%s:False"' % email},
+        save_cookies=options.save_cookies)
+    # Don't try to talk to ClientLogin.
+    server.authenticated = True
+    return server
+
+  return rpc_server_class(options.server, GetUserCredentials,
+                          host_override=options.host,
+                          save_cookies=options.save_cookies)
+
+
+def EncodeMultipartFormData(fields, files):
+  """Encode form fields for multipart/form-data.
+
+  Args:
+    fields: A sequence of (name, value) elements for regular form fields.
+    files: A sequence of (name, filename, value) elements for data to be
+           uploaded as files.
+  Returns:
+    (content_type, body) ready for httplib.HTTP instance.
+
+  Source:
+    http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/146306
+  """
+  BOUNDARY = '-M-A-G-I-C---B-O-U-N-D-A-R-Y-'
+  CRLF = '\r\n'
+  lines = []
+  for (key, value) in fields:
+    lines.append('--' + BOUNDARY)
+    lines.append('Content-Disposition: form-data; name="%s"' % key)
+    lines.append('')
+    lines.append(value)
+  for (key, filename, value) in files:
+    lines.append('--' + BOUNDARY)
+    lines.append('Content-Disposition: form-data; name="%s"; filename="%s"' %
+             (key, filename))
+    lines.append('Content-Type: %s' % GetContentType(filename))
+    lines.append('')
+    lines.append(value)
+  lines.append('--' + BOUNDARY + '--')
+  lines.append('')
+  body = CRLF.join(lines)
+  content_type = 'multipart/form-data; boundary=%s' % BOUNDARY
+  return content_type, body
+
+
+def GetContentType(filename):
+  """Helper to guess the content-type from the filename."""
+  return mimetypes.guess_type(filename)[0] or 'application/octet-stream'
+
+
+# Use a shell for subcommands on Windows to get a PATH search.
+use_shell = sys.platform.startswith("win")
+
+
+def RunShell(command, silent_ok=False, universal_newlines=False):
+  logging.info("Running %s", command)
+  p = subprocess.Popen(command, stdout=subprocess.PIPE,
+                       stderr=subprocess.STDOUT, shell=use_shell,
+                       universal_newlines=universal_newlines)
+  data = p.stdout.read()
+  p.wait()
+  p.stdout.close()
+  if p.returncode:
+    ErrorExit("Got error status from %s" % command)
+  if not silent_ok and not data:
+    ErrorExit("No output from %s" % command)
+  return data
+
+
+class VersionControlSystem(object):
+  """Abstract base class providing an interface to the VCS."""
+
+  def GenerateDiff(self, args):
+    """Return the current diff as a string.
+
+    Args:
+      args: Extra arguments to pass to the diff command.
+    """
+    raise NotImplementedError(
+        "abstract method -- subclass %s must override" % self.__class__)
+
+  def GetUnknownFiles(self):
+    """Return a list of files unknown to the VCS."""
+    raise NotImplementedError(
+        "abstract method -- subclass %s must override" % self.__class__)
+
+  def CheckForUnknownFiles(self):
+    """Show an "are you sure?" prompt if there are unknown files."""
+    unknown_files = self.GetUnknownFiles()
+    if unknown_files:
+      print "The following files are not added to version control:"
+      for line in unknown_files:
+        print line
+      prompt = "Are you sure to continue?(y/N) "
+      answer = raw_input(prompt).strip()
+      if answer != "y":
+        ErrorExit("User aborted")
+
+  def GetBaseFile(self, filename):
+    """Get the content of the upstream version of a file.
+
+    Returns:
+      A tuple (content, status) representing the file content and the status of
+      the file.
+    """
+
+    raise NotImplementedError(
+        "abstract method -- subclass %s must override" % self.__class__)
+
+  def UploadBaseFiles(self, issue, rpc_server, patch_list, patchset, options):
+    """Uploads the base files."""
+    patches = dict()
+    [patches.setdefault(v, k) for k, v in patch_list]
+    for filename in patches.keys():
+      content, status = self.GetBaseFile(filename)
+      no_base_file = False
+      if len(content) > MAX_UPLOAD_SIZE:
+        print ("Not uploading the base file for " + filename +
+               " because the file is too large.")
+        no_base_file = True
+        content = ""
+      checksum = md5.new(content).hexdigest()
+      if options.verbose > 0:
+        print "Uploading %s" % filename
+      url = "/%d/upload_content/%d/%d" % (int(issue), int(patchset),
+                                          int(patches.get(filename)))
+      form_fields = [("filename", filename),
+                     ("status", status),
+                     ("checksum", checksum),]
+      if no_base_file:
+        form_fields.append(("no_base_file", "1"))
+      if options.email:
+        form_fields.append(("user", options.email))
+      ctype, body = EncodeMultipartFormData(form_fields,
+                                            [("data", filename, content)])
+      response_body = rpc_server.Send(url, body, content_type=ctype)
+      if not response_body.startswith("OK"):
+        StatusUpdate("  --> %s" % response_body)
+        sys.exit(False)
+
+
+class SubversionVCS(VersionControlSystem):
+  """Implementation of the VersionControlSystem interface for Subversion."""
+
+  def GuessBase(self, required):
+    """Returns the SVN base URL.
+
+    Args:
+      required: If true, exits if the url can't be guessed, otherwise None is
+        returned.
+    """
+    info = RunShell(["svn", "info"])
+    for line in info.splitlines():
+      words = line.split()
+      if len(words) == 2 and words[0] == "URL:":
+        url = words[1]
+        scheme, netloc, path, params, query, fragment = urlparse.urlparse(url)
+        username, netloc = urllib.splituser(netloc)
+        if username:
+          logging.info("Removed username from base URL")
+        if netloc.endswith("svn.python.org"):
+          if netloc == "svn.python.org":
+            if path.startswith("/projects/"):
+              path = path[9:]
+          elif netloc != "pythondev@svn.python.org":
+            ErrorExit("Unrecognized Python URL: %s" % url)
+          base = "http://svn.python.org/view/*checkout*%s/" % path
+          logging.info("Guessed Python base = %s", base)
+        elif netloc.endswith("svn.collab.net"):
+          if path.startswith("/repos/"):
+            path = path[6:]
+          base = "http://svn.collab.net/viewvc/*checkout*%s/" % path
+          logging.info("Guessed CollabNet base = %s", base)
+        elif netloc.endswith(".googlecode.com"):
+          path = path + "/"
+          base = urlparse.urlunparse(("http", netloc, path, params,
+                                      query, fragment))
+          logging.info("Guessed Google Code base = %s", base)
+        else:
+          path = path + "/"
+          base = urlparse.urlunparse((scheme, netloc, path, params,
+                                      query, fragment))
+          logging.info("Guessed base = %s", base)
+        return base
+    if required:
+      ErrorExit("Can't find URL in output from svn info")
+    return None
+
+  def GenerateDiff(self, args):
+    cmd = ["svn", "diff"]
+    if not sys.platform.startswith("win"):
+      cmd.append("--diff-cmd=diff")
+    cmd.extend(args)
+    data = RunShell(cmd)
+    count = 0
+    for line in data.splitlines():
+      if line.startswith("Index:") or line.startswith("Property changes on:"):
+        count += 1
+        logging.info(line)
+    if not count:
+      ErrorExit("No valid patches found in output from svn diff")
+    return data
+
+  def _CollapseKeywords(self, content, keyword_str):
+    """Collapses SVN keywords."""
+    # svn cat translates keywords but svn diff doesn't. As a result of this
+    # behavior patching.PatchChunks() fails with a chunk mismatch error.
+    # This part was originally written by the Review Board development team
+    # who had the same problem (http://reviews.review-board.org/r/276/).
+    # Mapping of keywords to known aliases
+    svn_keywords = {
+      # Standard keywords
+      'Date':                ['Date', 'LastChangedDate'],
+      'Revision':            ['Revision', 'LastChangedRevision', 'Rev'],
+      'Author':              ['Author', 'LastChangedBy'],
+      'HeadURL':             ['HeadURL', 'URL'],
+      'Id':                  ['Id'],
+
+      # Aliases
+      'LastChangedDate':     ['LastChangedDate', 'Date'],
+      'LastChangedRevision': ['LastChangedRevision', 'Rev', 'Revision'],
+      'LastChangedBy':       ['LastChangedBy', 'Author'],
+      'URL':                 ['URL', 'HeadURL'],
+    }
+    def repl(m):
+       if m.group(2):
+         return "$%s::%s$" % (m.group(1), " " * len(m.group(3)))
+       return "$%s$" % m.group(1)
+    keywords = [keyword
+                for name in keyword_str.split(" ")
+                for keyword in svn_keywords.get(name, [])]
+    return re.sub(r"\$(%s):(:?)([^\$]+)\$" % '|'.join(keywords), repl, content)
+
+  def GetUnknownFiles(self):
+    status = RunShell(["svn", "status", "--ignore-externals"], silent_ok=True)
+    unknown_files = []
+    for line in status.split("\n"):
+      if line and line[0] == "?":
+        unknown_files.append(line)
+    return unknown_files
+
+  def GetBaseFile(self, filename):
+    status = RunShell(["svn", "status", "--ignore-externals", filename])
+    if not status:
+      StatusUpdate("svn status returned no output for %s" % filename)
+      sys.exit(False)
+    status_lines = status.splitlines()
+    # If file is in a cl, the output will begin with
+    # "\n--- Changelist 'cl_name':\n".  See
+    # http://svn.collab.net/repos/svn/trunk/notes/changelist-design.txt
+    if (len(status_lines) == 3 and
+        not status_lines[0] and
+        status_lines[1].startswith("--- Changelist")):
+      status = status_lines[2]
+    else:
+      status = status_lines[0]
+    # If a file is copied its status will be "A  +", which signifies
+    # "addition-with-history".  See "svn st" for more information.  We need to
+    # upload the original file or else diff parsing will fail if the file was
+    # edited.
+    if ((status[0] == "A" and status[3] != "+") or
+        (status[0] == " " and status[1] == "M")):  # property changed
+      content = ""
+    elif (status[0] in ("M", "D", "R") or
+          (status[0] == "A" and status[3] == "+")):
+      mimetype = RunShell(["svn", "-rBASE", "propget", "svn:mime-type",
+                           filename],
+                          silent_ok=True)
+      if mimetype.startswith("application/octet-stream"):
+        content = ""
+      else:
+        # On Windows svn cat gives \r\n, and calling subprocess.Popen turns
+        # them into \r\r\n, so use universal newlines to avoid the extra \r.
+        if sys.platform.startswith("win"):
+          nl = True
+        else:
+          nl = False
+        content = RunShell(["svn", "cat", filename], universal_newlines=nl)
+      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", "--exclude-standard", "--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:
+    A list of 2-tuple (filename, text) where text is the svn diff output
+      pertaining to filename.
+  """
+  patches = []
+  filename = None
+  diff = []
+  for line in data.splitlines(True):
+    new_filename = None
+    if line.startswith('Index:'):
+      unused, new_filename = line.split(':', 1)
+      new_filename = new_filename.strip()
+    elif line.startswith('Property changes on:'):
+      unused, temp_filename = line.split(':', 1)
+      # When a file is modified, paths use '/' between directories, however
+      # when a property is modified '\' is used on Windows.  Make them the same
+      # otherwise the file shows up twice.
+      temp_filename = temp_filename.strip().replace('\\', '/')
+      if temp_filename != filename:
+        # File has property changes but no modifications, create a new diff.
+        new_filename = temp_filename
+    if new_filename:
+      if filename and diff:
+        patches.append((filename, ''.join(diff)))
+      filename = new_filename
+      diff = [line]
+      continue
+    if diff is not None:
+      diff.append(line)
+  if filename and diff:
+    patches.append((filename, ''.join(diff)))
+  return patches
+
+
+def UploadSeparatePatches(issue, rpc_server, patchset, data, options):
+  """Uploads a separate patch for each file in the diff output.
+
+  Returns a list of [patch_key, filename] for each file.
+  """
+  patches = SplitPatch(data)
+  rv = []
+  for patch in patches:
+    if len(patch[1]) > MAX_UPLOAD_SIZE:
+      print ("Not uploading the patch for " + patch[0] +
+             " because the file is too large.")
+      continue
+    form_fields = [("filename", patch[0])]
+    if options.local_base:
+      form_fields.append(("content_upload", "1"))
+    files = [("data", "data.diff", patch[1])]
+    ctype, body = EncodeMultipartFormData(form_fields, files)
+    url = "/%d/upload_patch/%d" % (int(issue), int(patchset))
+    print "Uploading patch for " + patch[0]
+    response_body = rpc_server.Send(url, body, content_type=ctype)
+    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.
+
+  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:
+    options.local_base = True
+    logging.info("Enabled upload of base file")
+  if not options.assume_yes:
+    vcs.CheckForUnknownFiles()
+  if data is None:
+    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: "
+  else:
+    prompt = "New issue subject: "
+  message = options.message or raw_input(prompt).strip()
+  if not message:
+    ErrorExit("A non-empty message is required")
+  rpc_server = GetRpcServer(options)
+  form_fields = [("subject", message)]
+  if base:
+    form_fields.append(("base", base))
+  if options.issue:
+    form_fields.append(("issue", str(options.issue)))
+  if options.email:
+    form_fields.append(("user", options.email))
+  if options.reviewers:
+    for reviewer in options.reviewers.split(','):
+      if reviewer.count("@") != 1 or "." not in reviewer.split("@")[1]:
+        ErrorExit("Invalid email address: %s" % reviewer)
+    form_fields.append(("reviewers", options.reviewers))
+  if options.cc:
+    for cc in options.cc.split(','):
+      if cc.count("@") != 1 or "." not in cc.split("@")[1]:
+        ErrorExit("Invalid email address: %s" % cc)
+    form_fields.append(("cc", options.cc))
+  description = options.description
+  if options.description_file:
+    if options.description:
+      ErrorExit("Can't specify description and description_file")
+    file = open(options.description_file, 'r')
+    description = file.read()
+    file.close()
+  if description:
+    form_fields.append(("description", description))
+  # If we're uploading base files, don't send the email before the uploads, so
+  # that it contains the file status.
+  if options.send_mail and not options.local_base:
+    form_fields.append(("send_mail", "1"))
+  if options.local_base:
+    form_fields.append(("content_upload", "1"))
+  if len(data) > MAX_UPLOAD_SIZE:
+    print "Patch is large, so uploading file patches separately."
+    files = []
+    form_fields.append(("separate_patches", "1"))
+  else:
+    files = [("data", "data.diff", data)]
+  ctype, body = EncodeMultipartFormData(form_fields, files)
+  response_body = rpc_server.Send("/upload", body, content_type=ctype)
+  if options.local_base or not files:
+    lines = response_body.splitlines()
+    if len(lines) >= 2:
+      msg = lines[0]
+      patchset = lines[1].strip()
+      patches = [x.split(" ", 1) for x in lines[2:]]
+    else:
+      msg = response_body
+  else:
+    msg = response_body
+  StatusUpdate(msg)
+  if not response_body.startswith("Issue created.") and \
+  not response_body.startswith("Issue updated."):
+    sys.exit(0)
+  issue = msg[msg.rfind("/")+1:]
+
+  if not files:
+    result = UploadSeparatePatches(issue, rpc_server, patchset, data, options)
+    if options.local_base:
+      patches = result
+
+  if options.local_base:
+    vcs.UploadBaseFiles(issue, rpc_server, patches, patchset, options)
+    if options.send_mail:
+      rpc_server.Send("/" + issue + "/mail", payload="")
+  return issue
+
+
+def main():
+  try:
+    RealMain(sys.argv)
+  except KeyboardInterrupt:
+    print
+    StatusUpdate("Interrupted.")
+    sys.exit(1)
+
+
+if __name__ == "__main__":
+  main()