blob: a795c923cb42735de6bf7d912002570aa9ae98dc [file] [log] [blame]
# Copyright (c) 2009 Google Inc. All rights reserved.
# Copyright (c) 2009 Apple Inc. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# MultiCommandTool provides a framework for writing svn-like/git-like tools
# which are called with the following format:
# tool-name [global options] command-name [command options]
import logging
import sys
from optparse import OptionParser, IndentedHelpFormatter, SUPPRESS_USAGE, make_option
from webkitpy.tool.grammar import pluralize
_log = logging.getLogger(__name__)
class TryAgain(Exception):
pass
class Command(object):
name = None
show_in_main_help = False
help_text = None
long_help = None
argument_names = None
def __init__(self, options=None, requires_local_commits=False):
self.required_arguments = self._parse_required_arguments(self.argument_names)
self.options = options
self.requires_local_commits = requires_local_commits
self._tool = None
# option_parser can be overriden by the tool using set_option_parser
# This default parser will be used for standalone_help printing.
self.option_parser = HelpPrintingOptionParser(usage=SUPPRESS_USAGE, add_help_option=False, option_list=self.options)
def _exit(self, code):
sys.exit(code)
# This design is slightly awkward, but we need the
# the tool to be able to create and modify the option_parser
# before it knows what Command to run.
def set_option_parser(self, option_parser):
self.option_parser = option_parser
self._add_options_to_parser()
def _add_options_to_parser(self):
options = self.options or []
for option in options:
self.option_parser.add_option(option)
# The tool calls bind_to_tool on each Command after adding it to its list.
def bind_to_tool(self, tool):
# Command instances can only be bound to one tool at a time.
if self._tool and tool != self._tool:
raise Exception("Command already bound to tool!")
self._tool = tool
@staticmethod
def _parse_required_arguments(argument_names):
required_args = []
if not argument_names:
return required_args
split_args = argument_names.split(" ")
for argument in split_args:
if argument[0] == '[':
# For now our parser is rather dumb. Do some minimal validation that
# we haven't confused it.
if argument[-1] != ']':
raise Exception("Failure to parse argument string %s. Argument %s is missing ending ]" % (argument_names, argument))
else:
required_args.append(argument)
return required_args
def name_with_arguments(self):
usage_string = self.name
if self.options:
usage_string += " [options]"
if self.argument_names:
usage_string += " " + self.argument_names
return usage_string
def parse_args(self, args):
return self.option_parser.parse_args(args)
def check_arguments_and_execute(self, options, args, tool=None):
if len(args) < len(self.required_arguments):
_log.error("%s required, %s provided. Provided: %s Required: %s\nSee '%s help %s' for usage." % (
pluralize(len(self.required_arguments), "argument"),
pluralize(len(args), "argument"),
"'%s'" % " ".join(args),
" ".join(self.required_arguments),
tool.name(),
self.name))
return 1
return self.execute(options, args, tool) or 0
def standalone_help(self):
help_text = self.name_with_arguments().ljust(len(self.name_with_arguments()) + 3) + self.help_text + "\n\n"
if self.long_help:
help_text += "%s\n\n" % self.long_help
help_text += self.option_parser.format_option_help(IndentedHelpFormatter())
return help_text
def execute(self, options, args, tool):
raise NotImplementedError('subclasses must implement')
# main() exists so that Commands can be turned into stand-alone scripts.
# Other parts of the code will likely require modification to work stand-alone.
def main(self, args=sys.argv):
(options, args) = self.parse_args(args)
# Some commands might require a dummy tool
return self.check_arguments_and_execute(options, args)
class HelpPrintingOptionParser(OptionParser):
def __init__(self, epilog_method=None, *args, **kwargs):
self.epilog_method = epilog_method
OptionParser.__init__(self, *args, **kwargs)
def error(self, msg):
self.print_usage(sys.stderr)
error_message = "%s: error: %s\n" % (self.get_prog_name(), msg)
# This method is overriden to add this one line to the output:
error_message += "\nType \"%s --help\" to see usage.\n" % self.get_prog_name()
self.exit(1, error_message)
# We override format_epilog to avoid the default formatting which would paragraph-wrap the epilog
# and also to allow us to compute the epilog lazily instead of in the constructor (allowing it to be context sensitive).
def format_epilog(self, epilog):
if self.epilog_method:
return "\n%s\n" % self.epilog_method()
return ""
class HelpCommand(Command):
name = "help"
help_text = "Display information about this program or its subcommands"
argument_names = "[COMMAND]"
def __init__(self):
options = [
make_option("-a", "--all-commands", action="store_true", dest="show_all_commands", help="Print all available commands"),
]
Command.__init__(self, options)
self.show_all_commands = False # A hack used to pass --all-commands to _help_epilog even though it's called by the OptionParser.
def _help_epilog(self):
# Only show commands which are relevant to this checkout's SCM system. Might this be confusing to some users?
if self.show_all_commands:
epilog = "All %prog commands:\n"
relevant_commands = self._tool.commands[:]
else:
epilog = "Common %prog commands:\n"
relevant_commands = list(filter(self._tool.should_show_in_main_help, self._tool.commands))
longest_name_length = max(map(lambda command: len(command.name), relevant_commands))
relevant_commands = sorted(relevant_commands, key=lambda command: command.name)
command_help_texts = map(lambda command: " %s %s\n" % (command.name.ljust(longest_name_length), command.help_text), relevant_commands)
epilog += "%s\n" % "".join(command_help_texts)
epilog += "See '%prog help --all-commands' to list all commands.\n"
epilog += "See '%prog help COMMAND' for more information on a specific command.\n"
return epilog.replace("%prog", self._tool.name()) # Use of %prog here mimics OptionParser.expand_prog_name().
# FIXME: This is a hack so that we don't show --all-commands as a global option:
def _remove_help_options(self):
for option in self.options:
self.option_parser.remove_option(option.get_opt_string())
def execute(self, options, args, tool):
if args:
command = self._tool.command_by_name(args[0])
if command:
print(command.standalone_help())
return 0
self.show_all_commands = options.show_all_commands
self._remove_help_options()
self.option_parser.print_help()
return 0
class MultiCommandTool(object):
global_options = None
def __init__(self, name=None, commands=None):
self._name = name or OptionParser(prog=name).get_prog_name() # OptionParser has nice logic for fetching the name.
# Allow the unit tests to disable command auto-discovery.
self.commands = commands or [cls() for cls in self._find_all_commands() if cls.name]
self.help_command = self.command_by_name(HelpCommand.name)
# Require a help command, even if the manual test list doesn't include one.
if not self.help_command:
self.help_command = HelpCommand()
self.commands.append(self.help_command)
for command in self.commands:
command.bind_to_tool(self)
@classmethod
def _add_all_subclasses(cls, class_to_crawl, seen_classes):
for subclass in class_to_crawl.__subclasses__():
if subclass not in seen_classes:
seen_classes.add(subclass)
cls._add_all_subclasses(subclass, seen_classes)
@classmethod
def _find_all_commands(cls):
commands = set()
cls._add_all_subclasses(Command, commands)
return sorted(commands, key=lambda typ: typ.__name__)
def name(self):
return self._name
def _create_option_parser(self):
usage = "Usage: %prog [options] COMMAND [ARGS]"
return HelpPrintingOptionParser(epilog_method=self.help_command._help_epilog, prog=self.name(), usage=usage)
@staticmethod
def _split_command_name_from_args(args):
# Assume the first argument which doesn't start with "-" is the command name.
command_index = 0
for arg in args:
if arg[0] != "-":
break
command_index += 1
else:
return (None, args[:])
command = args[command_index]
return (command, args[:command_index] + args[command_index + 1:])
def command_by_name(self, command_name):
for command in self.commands:
if command_name == command.name:
return command
return None
def path(self):
raise NotImplementedError('subclasses must implement')
def command_completed(self):
pass
def should_show_in_main_help(self, command):
return command.show_in_main_help
def should_execute_command(self, command):
return True
def _add_global_options(self, option_parser):
global_options = self.global_options or []
for option in global_options:
option_parser.add_option(option)
def handle_global_options(self, options):
pass
def main(self, argv=sys.argv):
(command_name, args) = self._split_command_name_from_args(argv[1:])
option_parser = self._create_option_parser()
self._add_global_options(option_parser)
command = self.command_by_name(command_name) or self.help_command
if not command:
option_parser.error("%s is not a recognized command" % command_name)
command.set_option_parser(option_parser)
(options, args) = command.parse_args(args)
self.handle_global_options(options)
(should_execute, failure_reason) = self.should_execute_command(command)
if not should_execute:
_log.error(failure_reason)
return 0 # FIXME: Should this really be 0?
while True:
try:
result = command.check_arguments_and_execute(options, args, self)
break
except TryAgain as e:
pass
self.command_completed()
return result