| # 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 webkitcorepy.string_utils 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: |
| pass |
| |
| self.command_completed() |
| return result |
