Revert "rebaseline_server: download actual-results.json files from GCS instead of SVN"

gm/rebaseline_server/download_actuals.py

 #!/usr/bin/python
 
 """
 Copyright 2014 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 Download actual GM results for a particular builder.
 """
 
 # System-level imports
+import contextlib
 import optparse
 import os
 import posixpath
 import re
+import shutil
+import sys
+import urllib
 import urllib2
+import urlparse
 
 # Imports from within Skia
-import fix_pythonpath  # must do this first
-from pyutils import gs_utils
-from pyutils import url_utils
+#
+# We need to add the 'gm' and 'tools' directories, so that we can import
+# gm_json.py and buildbot_globals.py.
+#
+# Make sure that these dirs are in the PYTHONPATH, but add them at the *end*
+# so any dirs that are already in the PYTHONPATH will be preferred.
+#
+# TODO(epoger): Is it OK for this to depend on the 'tools' dir, given that
+# the tools dir is dependent on the 'gm' dir (to import gm_json.py)?
+TRUNK_DIRECTORY = os.path.dirname(os.path.dirname(os.path.dirname(__file__)))
+GM_DIRECTORY = os.path.join(TRUNK_DIRECTORY, 'gm')
+TOOLS_DIRECTORY = os.path.join(TRUNK_DIRECTORY, 'tools')
+if GM_DIRECTORY not in sys.path:
+  sys.path.append(GM_DIRECTORY)
+if TOOLS_DIRECTORY not in sys.path:
+  sys.path.append(TOOLS_DIRECTORY)
 import buildbot_globals
 import gm_json
 
+# Imports from third-party code
+APICLIENT_DIRECTORY = os.path.join(
+    TRUNK_DIRECTORY, 'third_party', 'externals', 'google-api-python-client')
+if APICLIENT_DIRECTORY not in sys.path:
+  sys.path.append(APICLIENT_DIRECTORY)
+from googleapiclient.discovery import build as build_service
+
 
 GM_SUMMARIES_BUCKET = buildbot_globals.Get('gm_summaries_bucket')
 DEFAULT_ACTUALS_BASE_URL = (
     'http://storage.googleapis.com/%s' % GM_SUMMARIES_BUCKET)
 DEFAULT_JSON_FILENAME = 'actual-results.json'
 
 
 class Download(object):
 
   def __init__(self, actuals_base_url=DEFAULT_ACTUALS_BASE_URL,
@@ skipping 37 matching lines @@
       results_of_this_type = actual_results_dict[result_type]
       if not results_of_this_type:
         continue
       for image_name in sorted(results_of_this_type.keys()):
         (test, config) = self._image_filename_re.match(image_name).groups()
         (hash_type, hash_digest) = results_of_this_type[image_name]
         source_url = gm_json.CreateGmActualUrl(
             test_name=test, hash_type=hash_type, hash_digest=hash_digest,
             gm_actuals_root_url=self._gm_actuals_root_url)
         dest_path = os.path.join(dest_dir, config, test + '.png')
-        url_utils.copy_contents(source_url=source_url, dest_path=dest_path,
-                                create_subdirs_if_needed=True)
+        # TODO(epoger): To speed this up, we should only download files that
+        # we don't already have on local disk.
+        copy_contents(source_url=source_url, dest_path=dest_path,
+                      create_subdirs_if_needed=True)
 
 
-def get_builders_list(summaries_bucket=GM_SUMMARIES_BUCKET):
-  """ Returns the list of builders we have actual results for.
+def create_filepath_url(filepath):
+  """ Returns a file:/// URL pointing at the given filepath on local disk.
+
+  For now, this is only used by unittests, but I anticipate it being useful
+  in production, as a way for developers to run rebaseline_server over locally
+  generated images.
+
+  TODO(epoger): Move this function, and copy_contents(), into a shared
+  utility module.  They are generally useful.
 
   Args:
-    summaries_bucket: Google Cloud Storage bucket containing the summary
-        JSON files
+    filepath: string; path to a file on local disk (may be absolute or relative,
+        and the file does not need to exist)
+
+  Returns:
+    A file:/// URL pointing at the file.  Regardless of whether filepath was
+        specified as a relative or absolute path, the URL will contain an
+        absolute path to the file.
+
+  Raises:
+    An Exception, if filepath is already a URL.
   """
-  dirs, _ = gs_utils.list_bucket_contents(bucket=GM_SUMMARIES_BUCKET)
-  return dirs
+  if urlparse.urlparse(filepath).scheme:
+    raise Exception('"%s" is already a URL' % filepath)
+  return urlparse.urljoin(
+      'file:', urllib.pathname2url(os.path.abspath(filepath)))
+
+
+def copy_contents(source_url, dest_path, create_subdirs_if_needed=False):
+  """ Copies the full contents of the URL 'source_url' into
+  filepath 'dest_path'.
+
+  Args:
+    source_url: string; complete URL to read from
+    dest_path: string; complete filepath to write to (may be absolute or
+        relative)
+    create_subdirs_if_needed: boolean; whether to create subdirectories as
+        needed to create dest_path
+
+  Raises:
+    Some subclass of Exception if unable to read source_url or write dest_path.
+  """
+  if create_subdirs_if_needed:
+    dest_dir = os.path.dirname(dest_path)
+    if not os.path.exists(dest_dir):
+      os.makedirs(dest_dir)
+  with contextlib.closing(urllib.urlopen(source_url)) as source_handle:
+    with open(dest_path, 'wb') as dest_handle:
+      shutil.copyfileobj(fsrc=source_handle, fdst=dest_handle)
+
+
+def gcs_list_bucket_contents(bucket, subdir=None):
+  """ Returns files in the Google Cloud Storage bucket as a (dirs, files) tuple.
+
+  Uses the API documented at
+  https://developers.google.com/storage/docs/json_api/v1/objects/list
+
+  Args:
+    bucket: name of the Google Storage bucket
+    subdir: directory within the bucket to list, or None for root directory
+  """
+  # The GCS command relies on the subdir name (if any) ending with a slash.
+  if subdir and not subdir.endswith('/'):
+    subdir += '/'
+  subdir_length = len(subdir) if subdir else 0
+
+  storage = build_service('storage', 'v1')
+  command = storage.objects().list(
+      bucket=bucket, delimiter='/', fields='items(name),prefixes',
+      prefix=subdir)
+  results = command.execute()
+
+  # The GCS command returned two subdicts:
+  # prefixes: the full path of every directory within subdir, with trailing '/'
+  # items: property dict for each file object within subdir
+  #        (including 'name', which is full path of the object)
+  dirs = []
+  for dir_fullpath in results.get('prefixes', []):
+    dir_basename = dir_fullpath[subdir_length:]
+    dirs.append(dir_basename[:-1])  # strip trailing slash
+  files = []
+  for file_properties in results.get('items', []):
+    file_fullpath = file_properties['name']
+    file_basename = file_fullpath[subdir_length:]
+    files.append(file_basename)
+  return (dirs, files)
 
 
 def main():
   parser = optparse.OptionParser()
   required_params = []
   parser.add_option('--actuals-base-url',
                     action='store', type='string',
                     default=DEFAULT_ACTUALS_BASE_URL,
                     help=('Base URL from which to read files containing JSON '
                           'summaries of actual GM results; defaults to '
@@ skipping 17 matching lines @@
   parser.add_option('--json-filename',
                     action='store', type='string',
                     default=DEFAULT_JSON_FILENAME,
                     help=('JSON summary filename to read for each builder; '
                           'defaults to "%default".'))
   parser.add_option('--list-builders', action='store_true',
                     help=('List all available builders.'))
   (params, remaining_args) = parser.parse_args()
 
   if params.list_builders:
-    print '\n'.join(get_builders_list())
+    dirs, _ = gcs_list_bucket_contents(bucket=GM_SUMMARIES_BUCKET)
+    print '\n'.join(dirs)
     return
 
   # Make sure all required options were set,
   # and that there were no items left over in the command line.
   for required_param in required_params:
     if not getattr(params, required_param):
       raise Exception('required option \'%s\' was not set' % required_param)
   if len(remaining_args) is not 0:
     raise Exception('extra items specified in the command line: %s' %
                     remaining_args)
 
   downloader = Download(actuals_base_url=params.actuals_base_url)
   downloader.fetch(builder_name=params.builder,
                    dest_dir=params.dest_dir)
 
 
 
 if __name__ == '__main__':
   main()