Add asset management scripts

infra/bots/assets/asset_utils.py

Index: infra/bots/assets/asset_utils.py
diff --git a/infra/bots/assets/asset_utils.py b/infra/bots/assets/asset_utils.py
new file mode 100644
index 0000000000000000000000000000000000000000..7326e60a17145c67eca71841bfb9a24b1d35d8e5
--- /dev/null
+++ b/infra/bots/assets/asset_utils.py
@@ -0,0 +1,125 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+
+"""Utilities for managing assets."""
+
+
+import argparse
+import os
+import shlex
+import subprocess
+import sys
+
+SKIA_DIR = os.path.abspath(os.path.realpath(os.path.join(
+    os.path.dirname(os.path.abspath(__file__)),
+    os.pardir, os.pardir, os.pardir)))
+INFRA_BOTS_DIR = os.path.join(SKIA_DIR, 'infra', 'bots')
+sys.path.insert(0, INFRA_BOTS_DIR)
+import utils
+import zip_utils
+
+
+DEFAULT_GS_BUCKET = 'skia-buildbots'
+GS_SUBDIR_TMPL = 'gs://%s/assets/%s'
+GS_PATH_TMPL = '%s/%s.zip'
+VERSION_FILENAME = 'VERSION'
+ZIP_BLACKLIST = ['.git', '.svn', '*.pyc', '.DS_STORE']
+
+
+class _GSWrapper(object):
+  """Wrapper object for interacting with Google Storage."""
+  def __init__(self, gsutil):
+    gsutil = os.path.abspath(gsutil) if gsutil else 'gsutil'
+    self._gsutil = [gsutil]
+    if gsutil.endswith('.py'):
+      self._gsutil = ['python', gsutil]
+
+  def copy(self, src, dst):
+    """Copy src to dst."""
+    subprocess.check_call(self._gsutil + ['cp', src, dst])
+
+  def list(self, path):
+    """List objects in the given path."""
+    try:
+      return subprocess.check_output(self._gsutil + ['ls', path]).splitlines()
+    except subprocess.CalledProcessError:
+      # If the prefix does not exist, we'll get an error, which is okay.
+      return []
+
+
+class Asset(object):
+  def __init__(self, name, gs_bucket, gsutil=None):
+    self._gs = _GSWrapper(gsutil)
+    self._gs_subdir = GS_SUBDIR_TMPL % (gs_bucket, name)
+    self._name = name
+
+  @property
+  def version_file(self):
+    """Return the path to the version file for this asset."""
+    return os.path.join(SKIA_DIR, 'infra', 'bots', 'assets', self._name,
+                        VERSION_FILENAME)
+
+  def get_current_version(self):
+    """Obtain the current version of the asset."""
+    with open(self.version_file) as f:
+      return int(f.read())
+
+  def get_available_versions(self):
+    """Return the existing version numbers for this asset."""
+    files = self._gs.list(self._gs_subdir)
+    bnames = [os.path.basename(f) for f in files]
+    suffix = '.zip'
+    versions = [int(f[:-len(suffix)]) for f in bnames if f.endswith(suffix)]
+    versions.sort()
+    return versions
+
+  def get_next_version(self):
+    """Find the next available version number for the asset."""
+    versions = self.get_available_versions()
+    if len(versions) == 0:
+      return 0
+    return versions[-1] + 1
+
+  def download_version(self, version, target_dir):
+    """Download the specified version of the asset."""
+    gs_path = GS_PATH_TMPL % (self._gs_subdir, str(version))
+    target_dir = os.path.abspath(target_dir)
+    with utils.tmp_dir():
+      zip_file = os.path.join(os.getcwd(), '%d.zip' % version)
+      self._gs.copy(gs_path, zip_file)
+      zip_utils.unzip(zip_file, target_dir)
+
+  def download_current_version(self, target_dir):
+    """Download the version of the asset specified in its version file."""
+    v = self.get_current_version()
+    self.download_version(v, target_dir)
+
+  def upload_new_version(self, target_dir, commit=False):
+    """Upload a new version and update the version file for the asset."""
+    version = self.get_next_version()
+    target_dir = os.path.abspath(target_dir)
+    with utils.tmp_dir():
+      zip_file = os.path.join(os.getcwd(), '%d.zip' % version)
+      zip_utils.zip(target_dir, zip_file, blacklist=ZIP_BLACKLIST)
+      gs_path = GS_PATH_TMPL % (self._gs_subdir, str(version))
+      self._gs.copy(zip_file, gs_path)
+
+    def _write_version():
+      with open(self.version_file, 'w') as f:
+        f.write(str(version))
+      subprocess.check_call([utils.GIT, 'add', self.version_file])
+
+    with utils.chdir(SKIA_DIR):
+      if commit:
+        with utils.git_branch():
+          _write_version()
+          subprocess.check_call([
+              utils.GIT, 'commit', '-m', 'Update %s version' % self._name])
+          subprocess.check_call([utils.GIT, 'cl', 'upload', '--bypass-hooks'])
+      else:
+        _write_version()