# -*- coding: utf-8 -*-
# Copyright 2011 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 gsutil help command."""
from __future__ import absolute_import
import itertools
import os
import pkgutil
import re
from subprocess import PIPE
from subprocess import Popen
import gslib.addlhelp
from gslib.command import Command
from gslib.command import OLD_ALIAS_MAP
import gslib.commands
from gslib.exception import CommandException
from gslib.help_provider import HelpProvider
from gslib.help_provider import MAX_HELP_NAME_LEN
from gslib.util import IsRunningInteractively
_SYNOPSIS = """
gsutil help [command or topic]
"""
_DETAILED_HELP_TEXT = ("""
SYNOPSIS
""" + _SYNOPSIS + """
DESCRIPTION
Running:
gsutil help
will provide a summary of all commands and additional topics on which
help is available.
Running:
gsutil help command or topic
will provide help about the specified command or topic.
Running:
gsutil help command sub-command
will provide help about the specified sub-command. For example, running:
gsutil help acl set
will provide help about the "set" subcommand of the "acl" command.
If you set the PAGER environment variable to the path to a pager program
(such as /bin/less on Linux), long help sections will be piped through
the specified pager.
""")
top_level_usage_string = (
'Usage: gsutil [-D] [-DD] [-h header]... '
'[-m] [-o] [-q] [command [opts...] args...]'
)
class HelpCommand(Command):
"""Implementation of gsutil help command."""
# Command specification. See base class for documentation.
command_spec = Command.CreateCommandSpec(
'help',
command_name_aliases=['?', 'man'],
usage_synopsis=_SYNOPSIS,
min_args=0,
max_args=2,
supported_sub_args='',
file_url_ok=True,
provider_url_ok=False,
urls_start_arg=0,
)
# Help specification. See help_provider.py for documentation.
help_spec = Command.HelpSpec(
help_name='help',
help_name_aliases=['?'],
help_type='command_help',
help_one_line_summary='Get help about commands and topics',
help_text=_DETAILED_HELP_TEXT,
subcommand_help_text={},
)
def RunCommand(self):
"""Command entry point for the help command."""
(help_type_map, help_name_map) = self._LoadHelpMaps()
output = []
if not self.args:
output.append('%s\nAvailable commands:\n' % top_level_usage_string)
format_str = ' %-' + str(MAX_HELP_NAME_LEN) + 's%s\n'
for help_prov in sorted(help_type_map['command_help'],
key=lambda hp: hp.help_spec.help_name):
output.append(format_str % (
help_prov.help_spec.help_name,
help_prov.help_spec.help_one_line_summary))
output.append('\nAdditional help topics:\n')
for help_prov in sorted(help_type_map['additional_help'],
key=lambda hp: hp.help_spec.help_name):
output.append(format_str % (
help_prov.help_spec.help_name,
help_prov.help_spec.help_one_line_summary))
output.append('\nUse gsutil help for detailed help.')
else:
invalid_subcommand = False
arg = self.args[0]
if arg not in help_name_map:
output.append('No help available for "%s"' % arg)
else:
help_prov = help_name_map[arg]
help_name = None
if len(self.args) > 1: # We also have a subcommand argument.
subcommand_map = help_prov.help_spec.subcommand_help_text
if subcommand_map and self.args[1] in subcommand_map:
help_name = arg + ' ' + self.args[1]
help_text = subcommand_map[self.args[1]]
else:
invalid_subcommand = True
if not subcommand_map:
output.append((
'The "%s" command has no subcommands. You can ask for the '
'full help by running:\n\n\tgsutil help %s\n') %
(arg, arg))
else:
subcommand_examples = []
for subcommand in subcommand_map:
subcommand_examples.append(
'\tgsutil help %s %s' % (arg, subcommand))
output.append(
('Subcommand "%s" does not exist for command "%s".\n'
'You can either ask for the full help about the command by '
'running:\n\n\tgsutil help %s\n\n'
'Or you can ask for help about one of the subcommands:\n\n%s'
) % (self.args[1], arg, arg, '\n'.join(subcommand_examples)))
if not invalid_subcommand:
if not help_name: # No subcommand or invalid subcommand.
help_name = help_prov.help_spec.help_name
help_text = help_prov.help_spec.help_text
output.append('NAME\n')
output.append(' %s - %s\n' % (
help_name, help_prov.help_spec.help_one_line_summary))
output.append('\n\n')
output.append(help_text.strip('\n'))
new_alias = OLD_ALIAS_MAP.get(arg, [None])[0]
if new_alias:
deprecation_warning = """
The "%s" alias is deprecated, and will eventually be removed completely.
Please use the "%s" command instead.""" % (arg, new_alias)
output.append('\n\n\nDEPRECATION WARNING\n')
output.append(deprecation_warning)
self._OutputHelp(''.join(output))
return 0
def _OutputHelp(self, help_str):
"""Outputs simply formatted string.
This function paginates if the string is too long, PAGER is defined, and
the output is a tty.
Args:
help_str: String to format.
"""
# Replace and with terminal formatting strings if connected to tty.
if not IsRunningInteractively():
help_str = re.sub('', '', help_str)
help_str = re.sub('', '', help_str)
print help_str
return
help_str = re.sub('', '\033[1m', help_str)
help_str = re.sub('', '\033[0;0m', help_str)
num_lines = len(help_str.split('\n'))
if 'PAGER' in os.environ and num_lines >= gslib.util.GetTermLines():
# Use -r option for less to make bolding work right.
pager = os.environ['PAGER'].split(' ')
if pager[0].endswith('less'):
pager.append('-r')
try:
Popen(pager, stdin=PIPE).communicate(input=help_str)
except OSError, e:
raise CommandException('Unable to open pager (%s): %s' %
(' '.join(pager), e))
else:
print help_str
def _LoadHelpMaps(self):
"""Returns tuple of help type and help name.
help type is a dict with key: help type
value: list of HelpProviders
help name is a dict with key: help command name or alias
value: HelpProvider
Returns:
(help type, help name)
"""
# Import all gslib.commands submodules.
for _, module_name, _ in pkgutil.iter_modules(gslib.commands.__path__):
__import__('gslib.commands.%s' % module_name)
# Import all gslib.addlhelp submodules.
for _, module_name, _ in pkgutil.iter_modules(gslib.addlhelp.__path__):
__import__('gslib.addlhelp.%s' % module_name)
help_type_map = {}
help_name_map = {}
for s in gslib.help_provider.ALL_HELP_TYPES:
help_type_map[s] = []
# Only include HelpProvider subclasses in the dict.
for help_prov in itertools.chain(
HelpProvider.__subclasses__(), Command.__subclasses__()):
if help_prov is Command:
# Skip the Command base class itself; we just want its subclasses,
# where the help command text lives (in addition to non-Command
# HelpProviders, like naming.py).
continue
gslib.help_provider.SanityCheck(help_prov, help_name_map)
help_name_map[help_prov.help_spec.help_name] = help_prov
for help_name_aliases in help_prov.help_spec.help_name_aliases:
help_name_map[help_name_aliases] = help_prov
help_type_map[help_prov.help_spec.help_type].append(help_prov)
return (help_type_map, help_name_map)