Add a module to fetch builds from different types of builders.

tools/auto_bisect/fetch_build.py

+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""This module contains functions for fetching and extracting archived builds.
+
+The builds may be stored in different places by different types builders;

[ojan, 2014/09/12 00:36:28]

types of builders.

[qyearsley, 2014/09/12 03:21:13]

Done.

+for example, builders on tryserver.chromium.perf stores builds in one place,
+while builders on chromium.linux store builds in another.
+
+This module can be either imported or run as a stand-alone script to download
+and extract a build.
+
+Usage: fetch_build.py <type> <revision> <output_dir> [options]
+"""
+
+import argparse
+import errno
+import os
+import shutil
+import sys
+import zipfile
+
+import bisect_utils
+import cloud_storage_wrapper as cloud_storage
+
+# Possible builder types.
+PERF_BUILDER = 'perf'
+FULL_BUILDER = 'full'
+
+
+def FetchBuild(builder_type, revision, output_dir, target_arch='x64',
+               target_platform='chromium', deps_patch_sha=None):
+  """Downloads and extracts a build for a particular revision.
+
+  If the build is successfully downloaded and extracted to |output_dir|, the
+  downloaded archive file is also deleted.
+
+  Args:
+    revision: Revision string, e.g. a git commit hash or SVN revision.
+    builder_type: Type of build archive.
+    target_arch: Architecture, e.g. "ia32".
+    target_platform: Platform name, e.g. "chromium" or "android".
+    deps_patch_sha: SHA1 hash of a DEPS file, if we want to fetch a build for
+        a Chromium revision with custom dependencies.
+
+  Raises:
+    IOError: Unzipping failed.
+    OSError: Directory creation or deletion failed.
+    NotImplementedError: The given builder type was not recognized.
+    RuntimeError: Some other error fetching this particular build.
+  """
+  build_archive = BuildArchive.Create(
+      builder_type, target_arch=target_arch, target_platform=target_platform)
+  bucket = build_archive.BucketName()
+  remote_path = build_archive.FilePath(revision, deps_patch_sha=deps_patch_sha)
+
+  filename = FetchFromCloudStorage(bucket, remote_path, output_dir)
+  if not filename:
+    raise RuntimeError('Failed to fetch gs://%s/%s.' % (bucket, remote_path))
+
+  Unzip(filename, output_dir)
+
+  # Delete downloaded zip file.

[ojan, 2014/09/12 00:36:27]

That's pretty clearly what the code does. No need for the comment. Use comments
for high-level documentation or to explain non-obvious things.

[qyearsley, 2014/09/12 03:21:13]

Done.

+  if os.path.exists(filename):
+    os.remove(filename)
+
+
+class BuildArchive(object):
+  """Represents a place where builds of some type are stored.
+
+  There are two pieces of information required to locate a file in Google
+  Cloud Storage, bucket name and file path. Subclasses of this class contain
+  specific logic about which bucket names and paths should be used to fetch
+  a build.
+  """
+
+  @staticmethod
+  def Create(builder_type, target_arch='x64', target_platform='chromium'):
+    """Creates a BuildArchive instance for fetching builds of some type."""

[ojan, 2014/09/12 00:36:28]

Ditto

[qyearsley, 2014/09/12 03:21:13]

Done.

+    if builder_type == PERF_BUILDER:
+      return PerfBuildArchive(target_arch, target_platform)
+    if builder_type == FULL_BUILDER:
+      return FullBuildArchive(target_arch, target_platform)
+    raise NotImplementedError('Builder type "%s" not supported.' % builder_type)
+
+  def __init__(self, target_arch='x86', target_platform='chromium'):
+    self._target_arch = target_arch
+    self._target_platform = target_platform
+
+  def BucketName(self):
+    """Returns the Google Cloud Storage bucket name to download from."""

[ojan, 2014/09/12 00:36:27]

Ditto

[qyearsley, 2014/09/12 03:21:13]

Done.

+    raise NotImplementedError()
+
+  def FilePath(self, revision, deps_patch_sha=None):
+    """Returns the remote file path to download a build from.
+
+    Args:
+      revision: A Chromium revision; this could be a git commit hash or
+          commit position or SVN revision number.
+      deps_patch_sha: The SHA1 hash of a patch to the DEPS file, which
+          uniquely identifies a change to use a particular revision of
+          a dependency.
+
+    Returns:
+      A file path, which not does not include a bucket name.
+    """
+    raise NotImplementedError()
+
+  def _ZipFileName(self, revision, deps_patch_sha=None):
+    """Gets the file name of a zip archive for a particular revision.
+
+    This returns a file name of the form full-build-<platform>_<revision>.zip,
+    which is a format used by multiple types of builders that store archives.
+
+    Args:
+      revision: A git commit hash or other revision string.
+      deps_patch_sha: SHA1 hash of a DEPS file patch.
+
+    Returns:
+      The archive file name.
+    """
+    base_name = 'full-build-%s' % self._PlatformName()
+    if deps_patch_sha:
+      revision = '%s_%s' % (revision , deps_patch_sha)
+    return '%s_%s.zip' % (base_name, revision)
+
+  @staticmethod
+  def _PlatformName():
+    """Return a string to be used in paths for the platform."""
+    if bisect_utils.IsWindowsHost() or bisect_utils.Is64BitWindows():
+      # Build archive for x64 is still stored with "win32" in the name.
+      return 'win32'
+    if bisect_utils.IsLinuxHost():
+      # Android builds are also stored with "linux" in the name.
+      return 'linux'
+    if bisect_utils.IsMacHost():
+      return 'mac'
+    raise NotImplementedError('Unknown platform "%s".' % sys.platform)
+
+
+class PerfBuildArchive(BuildArchive):
+  """Provides information about where perf builds are stored."""

[ojan, 2014/09/12 00:36:28]

I'll stop commenting about removing comments...but most of the ones in this file
just say what the function name clearly does.

[qyearsley, 2014/09/12 03:21:13]

Done.

+
+  def BucketName(self):
+    """Returns the Google Cloud Storage bucket name."""
+    return 'chrome-perf'
+
+  def FilePath(self, revision, deps_patch_sha=None):
+    """Returns the remote file path to download a build from."""
+    return '%s/%s' % (self._ArchiveDirectory(),
+                      self._ZipFileName(revision, deps_patch_sha))
+
+  def _ArchiveDirectory(self):
+    """Returns the directory name to download builds from."""
+    if bisect_utils.Is64BitWindows() and self._target_arch == 'x64':
+      return 'Win x64 Builder'
+    if bisect_utils.IsWindowsHost():
+      return 'Win Builder'
+    if bisect_utils.IsLinuxHost() and self._target_platform == 'android':
+      return 'android_perf_rel'
+    if bisect_utils.IsLinuxHost():
+      return 'Linux Builder'
+    if bisect_utils.IsMacHost():
+      return 'Mac Builder'
+    raise NotImplementedError('Unsupported Platform: "%s".' % sys.platform)
+
+
+class FullBuildArchive(BuildArchive):
+  """Provides information about where perf builds are stored."""
+
+  def BucketName(self):
+    """Returns the Google Cloud Storage bucket name."""
+    if bisect_utils.IsWindowsHost() or bisect_utils.Is64BitWindows():
+      return 'chromium-win-archive'
+    if bisect_utils.IsLinuxHost() and self._target_platform == 'android':
+      return 'chromium-android'
+    if bisect_utils.IsLinuxHost():
+      return 'chromium-linux-archive'
+    if bisect_utils.IsMacHost():
+      return 'chromium-mac-archive'
+    raise NotImplementedError('Unknown platform "%s".' % sys.platform)
+
+  def FilePath(self, revision, deps_patch_sha=None):
+    """Returns the remote file path to download a build from."""
+    return '%s/%s' % (self._ArchiveDirectory(),
+                      self._ZipFileName(revision, deps_patch_sha))
+
+  def _ArchiveDirectory(self):
+    """Returns the remote directory to download builds from."""
+    if bisect_utils.Is64BitWindows() and self._target_arch == 'x64':

[ojan, 2014/09/12 00:36:28]

This sort of manual mapping isn't going to work long-term. We have dozens of
configurations on the main waterfall. We need a more generic solution. I don't
have a good suggestion for how this should work though.

[qyearsley, 2014/09/12 03:21:13]

On first thought, the only way I could think of besides a manual mapping would
be
 (1) if there were always a systematic way of naming the directories based on
platform. But this may vary with master name, and android doesn't fit in with
the others.
 (2) if there were some way that this code could depend on and call some
function somewhere else in the code that determines where the builds are stored.

+      return 'chromium.win/Win x64 Builder'
+    if bisect_utils.IsWindowsHost():
+      return 'chromium.win/Win Builder'
+    if bisect_utils.IsLinuxHost() and self._target_platform == 'android':
+      return 'android_main_rel'
+    if bisect_utils.IsLinuxHost():
+      return 'chromium.linux/Linux Builder'
+    if bisect_utils.Mac():
+      return 'chromium.mac/Mac Builder'
+    raise NotImplementedError('Unknown platform "%s".' % sys.platform)
+
+
+def FetchFromCloudStorage(bucket_name, source_path, destination_dir):
+  """Fetches file(s) from the Google Cloud Storage.
+
+  As a side-effect, this prints messages to stdout about what's happening.
+
+  Args:
+    bucket_name: Google Storage bucket name.
+    source_path: Source file path.
+    destination_dir: Destination file path.
+
+  Returns:
+    Local file path of downloaded file if it was downloaded. If the file does
+    not exist in the given bucket, or if there was an error while downloading,
+    None is returned.
+  """
+  target_file = os.path.join(destination_dir, os.path.basename(source_path))
+  gs_url = 'gs://%s/%s' % (bucket_name, source_path)
+  try:
+    if cloud_storage.Exists(bucket_name, source_path):
+      print 'Fetching file from %s...' % gs_url
+      cloud_storage.Get(bucket_name, source_path, target_file)
+      if os.path.exists(target_file):
+        return target_file
+    else:
+      print 'File %s not found in cloud storage.' % gs_url
+  except Exception as e:
+    print 'Exception while fetching from cloud storage: %s' % e
+    if os.path.exists(target_file):
+      os.remove(target_file)
+  return None
+
+
+def Unzip(filename, output_dir, verbose=True):
+  """Extracts a zip archive's contents into the given output directory.
+
+  This was based on ExtractZip from build/scripts/common/chromium_utils.py.
+
+  Args:
+    filename: Name of the zip file to extract.
+    output_dir: Path to the destination directory.
+    verbose: Whether to print out what is being extracted.
+
+  Raises:
+    IOError: The unzip command had a non-zero exit code.
+    RuntimeError: Failed to create the output directory.
+  """
+  _MakeDirectory(output_dir)
+
+  # On Linux and Mac, we use the unzip command because it handles links and
+  # file permissions bits, so achieving this behavior is easier than with
+  # ZipInfo options.
+  #
+  # The Mac Version of unzip unfortunately does not support Zip64, whereas
+  # the python module does, so we have to fall back to the python zip module
+  # on Mac if the file size is greater than 4GB.
+  mac_zip_size_limit = 2 ** 32  # 4GB
+  if (bisect_utils.IsLinuxHost() or
+      (bisect_utils.IsMacHost()
+       and os.path.getsize(filename) < mac_zip_size_limit)):
+    unzip_command = ['unzip', '-o']
+    _UnzipUsingCommand(unzip_command, filename, output_dir)
+    return
+
+  # On Windows, try to use 7z if it is installed, otherwise fall back to the
+  # Python zipfile module. If 7z is not installed, then this may fail if the
+  # zip file is larger than 512MB.
+  sevenzip_path = r'C:\Program Files\7-Zip\7z.exe'
+  if (bisect_utils.IsWindowsHost() and os.path.exists(sevenzip_path)):
+    unzip_command = [sevenzip_path, 'x', '-y']
+    _UnzipUsingCommand(unzip_command, filename, output_dir)
+    return
+
+  _UnzipUsingZipFile(filename, output_dir, verbose)
+
+
+def _UnzipUsingCommand(unzip_command, filename, output_dir):
+  """Extracts a zip file using an external command.
+
+  Args:
+    unzip_command: An unzipping command, as a string list, without the filename.
+    filename: Path to the zip file.
+    output_dir: The directory which the contents should be extracted to.
+
+  Raises:
+    IOError: The command had a non-zero exit code.
+  """
+  absolute_filepath = os.path.abspath(filename)
+  command = unzip_command + [absolute_filepath]
+  return_code = _RunCommandInDirectory(output_dir, command)
+  if return_code:
+    _RmTree(output_dir)
+    raise IOError('Unzip failed: %s => %s' % (str(command), return_code))
+
+
+def _RunCommandInDirectory(directory, command):
+  """Changes to a directory, runs a command, then changes back."""
+  saved_dir = os.getcwd()
+  os.chdir(directory)
+  return_code = bisect_utils.RunProcess(command)
+  os.chdir(saved_dir)
+  return return_code
+
+
+def _UnzipUsingZipFile(filename, output_dir, verbose=True):
+  """Extracts a zip file using the Python zipfile module."""
+  assert bisect_utils.IsWindowsHost() or bisect_utils.IsMacHost()
+  zf = zipfile.ZipFile(filename)
+  for name in zf.namelist():
+    if verbose:
+      print 'Extracting %s' % name
+    zf.extract(name, output_dir)
+    if bisect_utils.IsMacHost():
+      # Restore file permission bits.
+      mode = zf.getinfo(name).external_attr >> 16
+      os.chmod(os.path.join(output_dir, name), mode)
+
+
+def _MakeDirectory(path):
+  """Creates a directory if it doesn't already exist."""
+  try:
+    os.makedirs(path)
+  except OSError as e:
+    if e.errno != errno.EEXIST:
+      raise
+
+
+def _RmTree(path):
+  """Removes the directory tree specified if it exists."""
+  try:
+    if os.path.exists(path):
+      shutil.rmtree(path)
+  except OSError, e:
+    if e.errno != errno.ENOENT:
+      raise
+
+
+def Main(argv):
+  """Downloads and extracts a build based on the command line arguments."""
+  parser = argparse.ArgumentParser()
+  parser.add_argument('builder_type')
+  parser.add_argument('revision')
+  parser.add_argument('output_dir')
+  parser.add_argument('--target-arch', default='ia32')
+  parser.add_argument('--target-platform', default='chromium')
+  parser.add_argument('--deps-patch-sha')
+  args = parser.parse_args(argv[1:])
+
+  FetchBuild(
+      args.builder_type, args.revision, args.output_dir,
+      target_arch=args.target_arch, target_platform=args.target_platform,
+      deps_patch_sha=args.deps_patch_sha)
+
+  print 'Build has been downloaded to and extracted in %s.' % args.output_dir
+
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(Main(sys.argv))
+