Revert of Bot update cleanup

recipe_modules/bot_update/resources/bot_update.py

Index: recipe_modules/bot_update/resources/bot_update.py
diff --git a/recipe_modules/bot_update/resources/bot_update.py b/recipe_modules/bot_update/resources/bot_update.py
index 4ecbf659711eb076f8310e3ae4c155400f850fda..39c4bf61d7868be0ac5d80162527447fdc8b1cff 100755
--- a/recipe_modules/bot_update/resources/bot_update.py
+++ b/recipe_modules/bot_update/resources/bot_update.py
@@ -73,17 +73,18 @@
 
 DEPOT_TOOLS_DIR = path.abspath(path.join(THIS_DIR, '..', '..', '..'))
 
+BUILD_INTERNAL_DIR = check_dir(
+    'build_internal', [
+        path.join(ROOT_DIR, 'build_internal'),
+        path.join(ROOT_DIR,      # .recipe_deps
+                  path.pardir,   # slave
+                  path.pardir,   # scripts
+                  path.pardir),  # build_internal
+    ])
+
+
 CHROMIUM_GIT_HOST = 'https://chromium.googlesource.com'
 CHROMIUM_SRC_URL = CHROMIUM_GIT_HOST + '/chromium/src.git'
-
-RECOGNIZED_PATHS = {
-    '/chrome/trunk/src':
-        CHROMIUM_SRC_URL,
-    '/chrome/trunk/src/tools/cros.DEPS':
-        CHROMIUM_GIT_HOST + '/chromium/src/tools/cros.DEPS.git',
-    '/chrome-internal/trunk/src-internal':
-        'https://chrome-internal.googlesource.com/chrome/src-internal.git',
-}
 
 # Official builds use buildspecs, so this is a special case.
 BUILDSPEC_TYPE = collections.namedtuple('buildspec',
@@ -167,8 +168,39 @@
 
 
 BOT_UPDATE_MESSAGE = """
-Bot Update Debugging information:
+What is the "Bot Update" step?
+==============================
+
+This step ensures that the source checkout on the bot (e.g. Chromium's src/ and
+its dependencies) is checked out in a consistent state. This means that all of
+the necessary repositories are checked out, no extra repositories are checked
+out, and no locally modified files are present.
+
+These actions used to be taken care of by the "gclient revert" and "update"
+steps. However, those steps are known to be buggy and occasionally flaky. This
+step has two main advantages over them:
+  * it only operates in Git, so the logic can be clearer and cleaner; and
+  * it is a slave-side script, so its behavior can be modified without
+    restarting the master.
+
+Why Git, you ask? Because that is the direction that the Chromium project is
+heading. This step is an integral part of the transition from using the SVN repo
+at chrome/trunk/src to using the Git repo src.git. Please pardon the dust while
+we fully convert everything to Git. This message will get out of your way
+eventually, and the waterfall will be a happier place because of it.
+
+This step can be activated or deactivated independently on every builder on
+every master. When it is active, the "gclient revert" and "update" steps become
+no-ops. When it is inactive, it prints this message, cleans up after itself, and
+lets everything else continue as though nothing has changed. Eventually, when
+everything is stable enough, this step will replace them entirely.
+
+Debugging information:
 (master/builder/slave may be unspecified on recipes)
+master: %(master)s
+builder: %(builder)s
+slave: %(slave)s
+forced by recipes: %(recipe)s
 CURRENT_DIR: %(CURRENT_DIR)s
 BUILDER_DIR: %(BUILDER_DIR)s
 SLAVE_DIR: %(SLAVE_DIR)s
@@ -176,7 +208,20 @@
 SCRIPTS_DIR: %(SCRIPTS_DIR)s
 BUILD_DIR: %(BUILD_DIR)s
 ROOT_DIR: %(ROOT_DIR)s
-DEPOT_TOOLS_DIR: %(DEPOT_TOOLS_DIR)s"""
+DEPOT_TOOLS_DIR: %(DEPOT_TOOLS_DIR)s
+bot_update.py is:"""
+
+ACTIVATED_MESSAGE = """ACTIVE.
+The bot will perform a Git checkout in this step.
+The "gclient revert" and "update" steps are no-ops.
+
+"""
+
+NOT_ACTIVATED_MESSAGE = """INACTIVE.
+This step does nothing. You actually want to look at the "update" step.
+
+"""
+
 
 GCLIENT_TEMPLATE = """solutions = %(solutions)s
 
@@ -186,14 +231,137 @@
 """
 
 
+internal_data = {}
+if BUILD_INTERNAL_DIR:
+  local_vars = {}
+  try:
+    execfile(os.path.join(
+        BUILD_INTERNAL_DIR, 'scripts', 'slave', 'bot_update_cfg.py'),
+        local_vars)
+  except Exception:
+    # Same as if BUILD_INTERNAL_DIR didn't exist in the first place.
+    print 'Warning: unable to read internal configuration file.'
+    print 'If this is an internal bot, this step may be erroneously inactive.'
+  internal_data = local_vars
+
+RECOGNIZED_PATHS = {
+    # If SVN path matches key, the entire URL is rewritten to the Git url.
+    '/chrome/trunk/src':
+        CHROMIUM_SRC_URL,
+    '/chrome/trunk/src/tools/cros.DEPS':
+        CHROMIUM_GIT_HOST + '/chromium/src/tools/cros.DEPS.git',
+}
+RECOGNIZED_PATHS.update(internal_data.get('RECOGNIZED_PATHS', {}))
+
+ENABLED_MASTERS = [
+    'bot_update.always_on',
+    'chromium.android',
+    'chromium.angle',
+    'chromium.chrome',
+    'chromium.chromedriver',
+    'chromium.chromiumos',
+    'chromium',
+    'chromium.fyi',
+    'chromium.goma',
+    'chromium.gpu',
+    'chromium.gpu.fyi',
+    'chromium.infra',
+    'chromium.infra.cron',
+    'chromium.linux',
+    'chromium.lkgr',
+    'chromium.mac',
+    'chromium.memory',
+    'chromium.memory.fyi',
+    'chromium.perf',
+    'chromium.perf.fyi',
+    'chromium.swarm',
+    'chromium.webkit',
+    'chromium.webrtc',
+    'chromium.webrtc.fyi',
+    'chromium.win',
+    'client.catapult',
+    'client.drmemory',
+    'client.mojo',
+    'client.nacl',
+    'client.nacl.ports',
+    'client.nacl.sdk',
+    'client.nacl.toolchain',
+    'client.pdfium',
+    'client.skia',
+    'client.skia.fyi',
+    'client.v8',
+    'client.v8.branches',
+    'client.v8.fyi',
+    'client.webrtc',
+    'client.webrtc.fyi',
+    'tryserver.blink',
+    'tryserver.client.catapult',
+    'tryserver.client.mojo',
+    'tryserver.chromium.android',
+    'tryserver.chromium.angle',
+    'tryserver.chromium.linux',
+    'tryserver.chromium.mac',
+    'tryserver.chromium.perf',
+    'tryserver.chromium.win',
+    'tryserver.infra',
+    'tryserver.nacl',
+    'tryserver.v8',
+    'tryserver.webrtc',
+]
+ENABLED_MASTERS += internal_data.get('ENABLED_MASTERS', [])
+
+ENABLED_BUILDERS = {
+    'client.dart.fyi': [
+        'v8-linux-release',
+        'v8-mac-release',
+        'v8-win-release',
+    ],
+    'client.dynamorio': [
+        'linux-v8-dr',
+    ],
+}
+ENABLED_BUILDERS.update(internal_data.get('ENABLED_BUILDERS', {}))
+
+ENABLED_SLAVES = {}
+ENABLED_SLAVES.update(internal_data.get('ENABLED_SLAVES', {}))
+
+# Disabled filters get run AFTER enabled filters, so for example if a builder
+# config is enabled, but a bot on that builder is disabled, that bot will
+# be disabled.
+DISABLED_BUILDERS = {}
+DISABLED_BUILDERS.update(internal_data.get('DISABLED_BUILDERS', {}))
+
+DISABLED_SLAVES = {}
+DISABLED_SLAVES.update(internal_data.get('DISABLED_SLAVES', {}))
+
+# These masters work only in Git, meaning for got_revision, always output
+# a git hash rather than a SVN rev.
+GIT_MASTERS = [
+    'client.v8',
+    'client.v8.branches',
+    'tryserver.v8',
+]
+GIT_MASTERS += internal_data.get('GIT_MASTERS', [])
+
+
 # How many times to try before giving up.
 ATTEMPTS = 5
 
+# Find deps2git
+DEPS2GIT_DIR_PATH = path.join(SCRIPTS_DIR, 'tools', 'deps2git')
+DEPS2GIT_PATH = path.join(DEPS2GIT_DIR_PATH, 'deps2git.py')
+S2G_INTERNAL_PATH = path.join(SCRIPTS_DIR, 'tools', 'deps2git_internal',
+                              'svn_to_git_internal.py')
 GIT_CACHE_PATH = path.join(DEPOT_TOOLS_DIR, 'git_cache.py')
 
 # Find the patch tool.
 if sys.platform.startswith('win'):
-  PATCH_TOOL = path.join(THIS_DIR, 'patch.EXE')
+  if not BUILD_INTERNAL_DIR:
+    print 'Warning: could not find patch tool because there is no '
+    print 'build_internal present.'
+    PATCH_TOOL = None
+  else:
+    PATCH_TOOL = path.join(BUILD_INTERNAL_DIR, 'tools', 'patch.EXE')
 else:
   PATCH_TOOL = '/usr/bin/patch'
 
@@ -222,6 +390,11 @@
 
 
 class InvalidDiff(Exception):
+  pass
+
+
+class Inactive(Exception):
+  """Not really an exception, just used to exit early cleanly."""
   pass
 
 
@@ -353,6 +526,34 @@
   }
 
 
+def check_enabled(master, builder, slave):
+  if master in ENABLED_MASTERS:
+    return True
+  builder_list = ENABLED_BUILDERS.get(master)
+  if builder_list and builder in builder_list:
+    return True
+  slave_list = ENABLED_SLAVES.get(master)
+  if slave_list and slave in slave_list:
+    return True
+  return False
+
+
+def check_disabled(master, builder, slave):
+  """Returns True if disabled, False if not disabled."""
+  builder_list = DISABLED_BUILDERS.get(master)
+  if builder_list and builder in builder_list:
+    return True
+  slave_list = DISABLED_SLAVES.get(master)
+  if slave_list and slave in slave_list:
+    return True
+  return False
+
+
+def check_valid_host(master, builder, slave):
+  return (check_enabled(master, builder, slave)
+          and not check_disabled(master, builder, slave))
+
+
 def maybe_ignore_revision(revision, buildspec):
   """Handle builders that don't care what buildbot tells them to build.
 
@@ -580,6 +781,17 @@
   return get_commit_message_footer_map(message).get(key)
 
 
+def get_svn_rev(git_hash, dir_name):
+  log = git('log', '-1', git_hash, cwd=dir_name)
+  git_svn_id = get_commit_message_footer(log, GIT_SVN_ID_FOOTER_KEY)
+  if not git_svn_id:
+    return None
+  m = GIT_SVN_ID_RE.match(git_svn_id)
+  if not m:
+    return None
+  return int(m.group(2))
+
+
 def get_git_hash(revision, branch, sln_dir):
   """We want to search for the SVN revision on the git-svn branch.
 
@@ -593,6 +805,59 @@
     return result
   raise SVNRevisionNotFound('We can\'t resolve svn r%s into a git hash in %s' %
                             (revision, sln_dir))
+
+
+def _last_commit_for_file(filename, repo_base):
+  cmd = ['log', '--format=%H', '--max-count=1', '--', filename]
+  return git(*cmd, cwd=repo_base).strip()
+
+
+def need_to_run_deps2git(repo_base, deps_file, deps_git_file):
+  """Checks to see if we need to run deps2git.
+
+  Returns True if there was a DEPS change after the last .DEPS.git update
+  or if DEPS has local modifications.
+  """
+  # See if DEPS is dirty
+  deps_file_status = git(
+      'status', '--porcelain', deps_file, cwd=repo_base).strip()
+  if deps_file_status and deps_file_status.startswith('M '):
+    return True
+
+  last_known_deps_ref = _last_commit_for_file(deps_file, repo_base)
+  last_known_deps_git_ref = _last_commit_for_file(deps_git_file, repo_base)
+  merge_base_ref = git('merge-base', last_known_deps_ref,
+                       last_known_deps_git_ref, cwd=repo_base).strip()
+
+  # If the merge base of the last DEPS and last .DEPS.git file is not
+  # equivilent to the hash of the last DEPS file, that means the DEPS file
+  # was committed after the last .DEPS.git file.
+  return last_known_deps_ref != merge_base_ref
+
+
+def ensure_deps2git(solution, shallow, git_cache_dir):
+  repo_base = path.join(os.getcwd(), solution['name'])
+  deps_file = path.join(repo_base, 'DEPS')
+  deps_git_file = path.join(repo_base, '.DEPS.git')
+  if (not git('ls-files', 'DEPS', cwd=repo_base).strip() or
+      not git('ls-files', '.DEPS.git', cwd=repo_base).strip()):
+    return
+
+  print 'Checking if %s is newer than %s' % (deps_file, deps_git_file)
+  if not need_to_run_deps2git(repo_base, deps_file, deps_git_file):
+    return
+
+  print '===DEPS file modified, need to run deps2git==='
+  cmd = [sys.executable, DEPS2GIT_PATH,
+         '--workspace', os.getcwd(),
+         '--cache_dir', git_cache_dir,
+         '--deps', deps_file,
+         '--out', deps_git_file]
+  if 'chrome-internal.googlesource' in solution['url']:
+    cmd.extend(['--extra-rules', S2G_INTERNAL_PATH])
+  if shallow:
+    cmd.append('--shallow')
+  call(*cmd)
 
 
 def emit_log_lines(name, lines):
@@ -659,7 +924,6 @@
   else:
     ref = branch if branch.startswith('refs/') else 'origin/%s' % branch
     git('checkout', '--force', ref, cwd=folder_name)
-
 
 def git_checkout(solutions, revisions, shallow, refs, git_cache_dir):
   build_dir = os.getcwd()
@@ -721,6 +985,16 @@
         else:
           raise
         remove(sln_dir)
+      except SVNRevisionNotFound:
+        tries_left -= 1
+        if tries_left > 0:
+          # If we don't have the correct revision, wait and try again.
+          print 'We can\'t find revision %s.' % revision
+          print 'The svn to git replicator is probably falling behind.'
+          print 'waiting 5 seconds and trying again...'
+          time.sleep(5)
+        else:
+          raise
 
     git('clean', '-dff', cwd=sln_dir)
 
@@ -729,6 +1003,16 @@
                     cwd=sln_dir).strip()
     first_solution = False
   return git_ref
+
+
+def _download(url):
+  """Fetch url and return content, with retries for flake."""
+  for attempt in xrange(ATTEMPTS):
+    try:
+      return urllib2.urlopen(url).read()
+    except Exception:
+      if attempt == ATTEMPTS - 1:
+        raise
 
 
 def parse_diff(diff):
@@ -940,8 +1224,12 @@
   return None
 
 
-def parse_got_revision(gclient_output, got_revision_mapping):
-  """Translate git gclient revision mapping to build properties."""
+def parse_got_revision(gclient_output, got_revision_mapping, use_svn_revs):
+  """Translate git gclient revision mapping to build properties.
+
+  If use_svn_revs is True, then translate git hashes in the revision mapping
+  to svn revision numbers.
+  """
   properties = {}
   solutions_output = {
       # Make sure path always ends with a single slash.
@@ -961,7 +1249,12 @@
       # Since we are using .DEPS.git, everything had better be git.
       assert solution_output.get('scm') == 'git'
       git_revision = git('rev-parse', 'HEAD', cwd=dir_name).strip()
-      revision = git_revision
+      if use_svn_revs:
+        revision = get_svn_rev(git_revision, dir_name)
+        if not revision:
+          revision = git_revision
+      else:
+        revision = git_revision
       commit_position = get_commit_position(dir_name)
 
     properties[property_name] = revision
@@ -993,6 +1286,7 @@
                                    revisions)
     if not revision:
       continue
+    # TODO(hinoka): Catch SVNRevisionNotFound error maybe?
     git('fetch', 'origin', cwd=deps_name)
     force_revision(deps_name, revision)
 
@@ -1028,6 +1322,11 @@
                              revision_mapping, git_ref, apply_issue_email_file,
                              apply_issue_key_file, whitelist=[target])
         already_patched.append(target)
+
+  if not buildspec:
+    # Run deps2git if there is a DEPS change after the last .DEPS.git commit.
+    for solution in solutions:
+      ensure_deps2git(solution, shallow, git_cache_dir)
 
   # Ensure our build/ directory is set up with the correct .gclient file.
   gclient_configure(solutions, target_os, target_os_only, git_cache_dir)
@@ -1132,6 +1431,8 @@
                    help='--private-key-file option passthrough for '
                         'apply_patch.py.')
   parse.add_option('--patch_url', help='Optional URL to SVN patch.')
+  parse.add_option('--root', dest='patch_root',
+                   help='DEPRECATED: Use --patch_root.')
   parse.add_option('--patch_root', help='Directory to patch on top of.')
   parse.add_option('--rietveld_server',
                    default='codereview.chromium.org',
@@ -1140,6 +1441,10 @@
                    help='Gerrit repository to pull the ref from.')
   parse.add_option('--gerrit_ref', help='Gerrit ref to apply.')
   parse.add_option('--specs', help='Gcilent spec.')
+  parse.add_option('--master', help='Master name.')
+  parse.add_option('-f', '--force', action='store_true',
+                   help='Bypass check to see if we want to be run. '
+                        'Should ONLY be used locally or by smart recipes.')
   parse.add_option('--revision_mapping',
                    help='{"path/to/repo/": "property_name"}')
   parse.add_option('--revision_mapping_file',
@@ -1155,6 +1460,11 @@
                         'set to <branch>:<revision>.')
   parse.add_option('--output_manifest', action='store_true',
                    help=('Add manifest json to the json output.'))
+  parse.add_option('--slave_name', default=socket.getfqdn().split('.')[0],
+                   help='Hostname of the current machine, '
+                   'used for determining whether or not to activate.')
+  parse.add_option('--builder_name', help='Name of the builder, '
+                   'used for determining whether or not to activate.')
   parse.add_option('--build_dir', default=os.getcwd())
   parse.add_option('--flag_file', default=path.join(os.getcwd(),
                                                     'update.flag'))
@@ -1216,17 +1526,25 @@
   return options, args
 
 
-def prepare(options, git_slns):
+def prepare(options, git_slns, active):
   """Prepares the target folder before we checkout."""
   dir_names = [sln.get('name') for sln in git_slns if 'name' in sln]
+  # If we're active now, but the flag file doesn't exist (we weren't active
+  # last run) or vice versa, blow away all checkouts.
+  if bool(active) != bool(check_flag(options.flag_file)):
+    ensure_no_checkout(dir_names, '*')
   if options.output_json:
     # Make sure we tell recipes that we didn't run if the script exits here.
-    emit_json(options.output_json, did_run=True)
-  if options.clobber:
-    ensure_no_checkout(dir_names, '*')
+    emit_json(options.output_json, did_run=active)
+  if active:
+    if options.clobber:
+      ensure_no_checkout(dir_names, '*')
+    else:
+      ensure_no_checkout(dir_names, '.svn')
+    emit_flag(options.flag_file)
   else:
-    ensure_no_checkout(dir_names, '.svn')
-  emit_flag(options.flag_file)
+    delete_flag(options.flag_file)
+    raise Inactive  # This is caught in main() and we exit cleanly.
 
   # Do a shallow checkout if the disk is less than 100GB.
   total_disk_space, free_disk_space = get_total_disk_space()
@@ -1253,7 +1571,7 @@
   return revisions, step_text
 
 
-def checkout(options, git_slns, specs, buildspec,
+def checkout(options, git_slns, specs, buildspec, master,
              svn_root, revisions, step_text):
   first_sln = git_slns[0]['name']
   dir_names = [sln.get('name') for sln in git_slns if 'name' in sln]
@@ -1315,6 +1633,9 @@
       print '@@@STEP_TEXT@%s PATCH FAILED@@@' % step_text
     raise
 
+  # Revision is an svn revision, unless it's a git master.
+  use_svn_rev = master not in GIT_MASTERS
+
   # Take care of got_revisions outputs.
   revision_mapping = dict(GOT_REVISION_MAPPINGS.get(svn_root, {}))
   if options.revision_mapping:
@@ -1326,7 +1647,8 @@
   if not revision_mapping:
     revision_mapping[first_sln] = 'got_revision'
 
-  got_revisions = parse_got_revision(gclient_output, revision_mapping)
+  got_revisions = parse_got_revision(gclient_output, revision_mapping,
+                                     use_svn_rev)
 
   if not got_revisions:
     # TODO(hinoka): We should probably bail out here, but in the interest
@@ -1351,9 +1673,22 @@
     emit_properties(got_revisions)
 
 
-def print_help_text(master, builder, slave):
+def print_help_text(force, output_json, active, master, builder, slave):
   """Print helpful messages to tell devs whats going on."""
+  if force and output_json:
+    recipe_force = 'Forced on by recipes'
+  elif active and output_json:
+    recipe_force = 'Off by recipes, but forced on by bot update'
+  elif not active and output_json:
+    recipe_force = 'Forced off by recipes'
+  else:
+    recipe_force = 'N/A. Was not called by recipes'
+
   print BOT_UPDATE_MESSAGE % {
+    'master': master or 'Not specified',
+    'builder': builder or 'Not specified',
+    'slave': slave or 'Not specified',
+    'recipe': recipe_force,
     'CURRENT_DIR': CURRENT_DIR,
     'BUILDER_DIR': BUILDER_DIR,
     'SLAVE_DIR': SLAVE_DIR,
@@ -1363,6 +1698,7 @@
     'ROOT_DIR': ROOT_DIR,
     'DEPOT_TOOLS_DIR': DEPOT_TOOLS_DIR,
   },
+  print ACTIVATED_MESSAGE if active else NOT_ACTIVATED_MESSAGE
 
 
 def main():
@@ -1372,8 +1708,12 @@
   slave = options.slave_name
   master = options.master
 
-  # Prints some debugging information.
-  print_help_text(master, builder, slave)
+  # Check if this script should activate or not.
+  active = check_valid_host(master, builder, slave) or options.force or False
+
+  # Print a helpful message to tell developers whats going on with this step.
+  print_help_text(
+      options.force, options.output_json, active, master, builder, slave)
 
   # Parse, munipulate, and print the gclient solutions.
   specs = {}
@@ -1386,10 +1726,13 @@
 
   try:
     # Dun dun dun, the main part of bot_update.
-    revisions, step_text = prepare(options, git_slns)
-    checkout(options, git_slns, specs, buildspec, svn_root, revisions,
+    revisions, step_text = prepare(options, git_slns, active)
+    checkout(options, git_slns, specs, buildspec, master, svn_root, revisions,
              step_text)
 
+  except Inactive:
+    # Not active, should count as passing.
+    pass
   except PatchFailed as e:
     emit_flag(options.flag_file)
     # Return a specific non-zero exit code for patch failure (because it is