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

third_party/gsutil/gslib/commands/cat.py

+# -*- coding: utf-8 -*-
+# Copyright 2011 Google Inc. All Rights Reserved.
+# Copyright 2011, Nexenta Systems Inc.
+#
+# 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 cat command for cloud storage providers."""
+
+from __future__ import absolute_import
+
+import re
+
+from gslib.cat_helper import CatHelper
+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.util import NO_MAX
+
+_SYNOPSIS = """
+  gsutil cat [-h] url...
+"""
+
+_DETAILED_HELP_TEXT = ("""
+<B>SYNOPSIS</B>
+""" + _SYNOPSIS + """
+
+
+<B>DESCRIPTION</B>
+  The cat command outputs the contents of one or more URLs to stdout.
+  It is equivalent to doing:
+
+    gsutil cp url... -
+
+  (The final '-' causes gsutil to stream the output to stdout.)
+
+
+<B>WARNING: DATA INTEGRITY CHECKING NOT DONE</B>
+  The gsutil cat command does not compute a checksum of the downloaded data.
+  Therefore, we recommend that users either perform their own validation of the
+  output of gsutil cat or use gsutil cp or rsync (both of which perform
+  integrity checking automatically).
+
+
+<B>OPTIONS</B>
+  -h          Prints short header for each object. For example:
+
+                gsutil cat -h gs://bucket/meeting_notes/2012_Feb/*.txt
+
+              This would print a header with the object name before the contents
+              of each text object that matched the wildcard.
+
+  -r range    Causes gsutil to output just the specified byte range of the
+              object. Ranges are can be of these forms:
+
+                start-end (e.g., -r 256-5939)
+                start-    (e.g., -r 256-)
+                -numbytes (e.g., -r -5)
+
+              where offsets start at 0, start-end means to return bytes start
+              through end (inclusive), start- means to return bytes start
+              through the end of the object, and -numbytes means to return the
+              last numbytes of the object. For example:
+
+                gsutil cat -r 256-939 gs://bucket/object
+
+              returns bytes 256 through 939, while:
+
+                gsutil cat -r -5 gs://bucket/object
+
+              returns the final 5 bytes of the object.
+""")
+
+
+class CatCommand(Command):
+  """Implementation of gsutil cat command."""
+
+  # Command specification. See base class for documentation.
+  command_spec = Command.CreateCommandSpec(
+      'cat',
+      command_name_aliases=[],
+      usage_synopsis=_SYNOPSIS,
+      min_args=1,
+      max_args=NO_MAX,
+      supported_sub_args='hr:',
+      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='cat',
+      help_name_aliases=[],
+      help_type='command_help',
+      help_one_line_summary='Concatenate object content to stdout',
+      help_text=_DETAILED_HELP_TEXT,
+      subcommand_help_text={},
+  )
+
+  # Command entry point.
+  def RunCommand(self):
+    """Command entry point for the cat command."""
+    show_header = False
+    request_range = None
+    start_byte = 0
+    end_byte = None
+    if self.sub_opts:
+      for o, a in self.sub_opts:
+        if o == '-h':
+          show_header = True
+        elif o == '-r':
+          request_range = a.strip()
+          range_matcher = re.compile(
+              '^(?P<start>[0-9]+)-(?P<end>[0-9]*)$|^(?P<endslice>-[0-9]+)$')
+          range_match = range_matcher.match(request_range)
+          if not range_match:
+            raise CommandException('Invalid range (%s)' % request_range)
+          if range_match.group('start'):
+            start_byte = long(range_match.group('start'))
+          if range_match.group('end'):
+            end_byte = long(range_match.group('end'))
+          if range_match.group('endslice'):
+            start_byte = long(range_match.group('endslice'))
+        else:
+          self.RaiseInvalidArgumentException()
+
+    return CatHelper(self).CatUrlStrings(self.args,
+                                         show_header=show_header,
+                                         start_byte=start_byte,
+                                         end_byte=end_byte)