[catapult] - Copy Telemetry's gsutilz over to third_party.

third_party/gsutil/gslib/commands/stat.py

+# -*- coding: utf-8 -*-
+# Copyright 2013 Google Inc. All Rights Reserved.
+#
+# 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.
+"""Implementation of Unix-like stat command for cloud storage providers."""
+
+from __future__ import absolute_import
+
+import logging
+
+from gslib.bucket_listing_ref import BucketListingObject
+from gslib.cloud_api import AccessDeniedException
+from gslib.cloud_api import NotFoundException
+from gslib.command import Command
+from gslib.command_argument import CommandArgument
+from gslib.cs_api_map import ApiSelector
+from gslib.exception import CommandException
+from gslib.exception import InvalidUrlError
+from gslib.storage_url import ContainsWildcard
+from gslib.storage_url import StorageUrlFromString
+from gslib.util import NO_MAX
+from gslib.util import PrintFullInfoAboutObject
+
+
+_SYNOPSIS = """
+  gsutil stat url...
+"""
+
+_DETAILED_HELP_TEXT = ("""
+<B>SYNOPSIS</B>
+""" + _SYNOPSIS + """
+
+
+<B>DESCRIPTION</B>
+  The stat command will output details about the specified object URLs.
+  It is similar to running:
+
+    gsutil ls -L gs://some-bucket/some-object
+
+  but is more efficient because it avoids performing bucket listings and gets
+  the minimum necessary amount of object metadata. Moreover, because it avoids
+  performing bucket listings (which are eventually consistent) the gsutil stat
+  command provides a strongly consistent way to check for the existence (and
+  read the metadata) of an object.
+
+  The gsutil stat command will, however, perform bucket listings if you specify
+  URLs using wildcards.
+
+  If run with the gsutil -q option nothing will be printed, e.g.:
+
+    gsutil -q stat gs://some-bucket/some-object
+
+  This can be useful for writing scripts, because the exit status will be 0 for
+  an existing object and 1 for a non-existent object.
+
+  Note: Unlike the gsutil ls command, the stat command does not support
+  operations on sub-directories. For example, if you run the command:
+
+    gsutil -q stat gs://some-bucket/some-subdir/
+
+  gsutil will look for information about an object called "some-subdir/" (with a
+  trailing slash) inside the bucket "some-bucket", as opposed to operating on
+  objects nested under gs://some-bucket/some-subdir/. Unless you actually have
+  an object with that name, the operation will fail. However, you can use the
+  stat command on objects within subdirectories. For example, this command will
+  work as expected:
+
+    gsutil -q stat gs://some-bucket/some-subdir/file.txt
+""")
+
+
+# TODO: Add ability to stat buckets.
+class StatCommand(Command):
+  """Implementation of gsutil stat command."""
+
+  # Command specification. See base class for documentation.
+  command_spec = Command.CreateCommandSpec(
+      'stat',
+      command_name_aliases=[],
+      usage_synopsis=_SYNOPSIS,
+      min_args=1,
+      max_args=NO_MAX,
+      supported_sub_args='',
+      file_url_ok=False,
+      provider_url_ok=False,
+      urls_start_arg=0,
+      gs_api_support=[ApiSelector.XML, ApiSelector.JSON],
+      gs_default_api=ApiSelector.JSON,
+      argparse_arguments=[
+          CommandArgument.MakeZeroOrMoreCloudURLsArgument()
+      ]
+  )
+  # Help specification. See help_provider.py for documentation.
+  help_spec = Command.HelpSpec(
+      help_name='stat',
+      help_name_aliases=[],
+      help_type='command_help',
+      help_one_line_summary='Display object status',
+      help_text=_DETAILED_HELP_TEXT,
+      subcommand_help_text={},
+  )
+
+  def RunCommand(self):
+    """Command entry point for stat command."""
+    # List of fields we'll print for stat objects.
+    stat_fields = ['updated', 'cacheControl', 'contentDisposition',
+                   'contentEncoding', 'contentLanguage', 'size', 'contentType',
+                   'componentCount', 'metadata', 'crc32c', 'md5Hash', 'etag',
+                   'generation', 'metageneration']
+    found_nonmatching_arg = False
+    for url_str in self.args:
+      arg_matches = 0
+      url = StorageUrlFromString(url_str)
+      if not url.IsObject():
+        raise CommandException('The stat command only works with object URLs')
+      try:
+        if ContainsWildcard(url_str):
+          blr_iter = self.WildcardIterator(url_str).IterObjects(
+              bucket_listing_fields=stat_fields)
+        else:
+          single_obj = self.gsutil_api.GetObjectMetadata(
+              url.bucket_name, url.object_name, generation=url.generation,
+              provider=url.scheme, fields=stat_fields)
+          blr_iter = [BucketListingObject(url, root_object=single_obj)]
+        for blr in blr_iter:
+          if blr.IsObject():
+            arg_matches += 1
+            if logging.getLogger().isEnabledFor(logging.INFO):
+              PrintFullInfoAboutObject(blr, incl_acl=False)
+      except AccessDeniedException:
+        logging.info('You aren\'t authorized to read %s - skipping', url_str)
+      except InvalidUrlError:
+        raise
+      except NotFoundException:
+        pass
+      if not arg_matches:
+        if logging.getLogger().isEnabledFor(logging.INFO):
+          logging.info('No URLs matched %s', url_str)
+        found_nonmatching_arg = True
+    if found_nonmatching_arg:
+      return 1
+    return 0