From 8f2ff4d7c902d534d68ff1a16418b7be492033bf Mon Sep 17 00:00:00 2001 From: Michael DeHaan Date: Thu, 7 Feb 2008 13:13:24 -0500 Subject: Carving away at func some more to just get down to cert items, still lots more to do. --- certmaster/overlord/command.py | 287 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 287 insertions(+) create mode 100644 certmaster/overlord/command.py (limited to 'certmaster/overlord/command.py') diff --git a/certmaster/overlord/command.py b/certmaster/overlord/command.py new file mode 100644 index 0000000..7fb7de4 --- /dev/null +++ b/certmaster/overlord/command.py @@ -0,0 +1,287 @@ +# -*- Mode: Python; test-case-name: test_command -*- +# vi:si:et:sw=4:sts=4:ts=4 + +# This file is released under the standard PSF license. +# +# from MOAP - https://thomas.apestaart.org/moap/trac +# written by Thomas Vander Stichele (thomas at apestaart dot org) +# + +""" +Command class. +""" + +import optparse +import sys + +from func.config import read_config, CONFIG_FILE +from func.commonconfig import CMConfig + +class CommandHelpFormatter(optparse.IndentedHelpFormatter): + """ + I format the description as usual, but add an overview of commands + after it if there are any, formatted like the options. + """ + _commands = None + + def addCommand(self, name, description): + if self._commands is None: + self._commands = {} + self._commands[name] = description + + ### override parent method + def format_description(self, description): + # textwrap doesn't allow for a way to preserve double newlines + # to separate paragraphs, so we do it here. + blocks = description.split('\n\n') + rets = [] + + for block in blocks: + rets.append(optparse.IndentedHelpFormatter.format_description(self, + block)) + ret = "\n".join(rets) + if self._commands: + commandDesc = [] + commandDesc.append("commands:") + keys = self._commands.keys() + keys.sort() + length = 0 + for key in keys: + if len(key) > length: + length = len(key) + for name in keys: + format = " %-" + "%d" % length + "s %s" + commandDesc.append(format % (name, self._commands[name])) + ret += "\n" + "\n".join(commandDesc) + "\n" + return ret + +class CommandOptionParser(optparse.OptionParser): + """ + I parse options as usual, but I explicitly allow setting stdout + so that our print_help() method (invoked by default with -h/--help) + defaults to writing there. + """ + _stdout = sys.stdout + + def set_stdout(self, stdout): + self._stdout = stdout + + # we're overriding the built-in file, but we need to since this is + # the signature from the base class + __pychecker__ = 'no-shadowbuiltin' + def print_help(self, file=None): + # we are overriding a parent method so we can't do anything about file + __pychecker__ = 'no-shadowbuiltin' + if file is None: + file = self._stdout + file.write(self.format_help()) + +class Command: + """ + I am a class that handles a command for a program. + Commands can be nested underneath a command for further processing. + + @cvar name: name of the command, lowercase + @cvar aliases: list of alternative lowercase names recognized + @type aliases: list of str + @cvar usage: short one-line usage string; + %command gets expanded to a sub-command or [commands] + as appropriate + @cvar summary: short one-line summary of the command + @cvar description: longer paragraph explaining the command + @cvar subCommands: dict of name -> commands below this command + @type subCommands: dict of str -> L{Command} + """ + name = None + aliases = None + usage = None + summary = None + description = None + parentCommand = None + subCommands = None + subCommandClasses = None + aliasedSubCommands = None + + def __init__(self, parentCommand=None, stdout=sys.stdout, + stderr=sys.stderr): + """ + Create a new command instance, with the given parent. + Allows for redirecting stdout and stderr if needed. + This redirection will be passed on to child commands. + """ + if not self.name: + self.name = str(self.__class__).split('.')[-1].lower() + self.stdout = stdout + self.stderr = stderr + self.parentCommand = parentCommand + + self.config = read_config(CONFIG_FILE, CMConfig) + + # create subcommands if we have them + self.subCommands = {} + self.aliasedSubCommands = {} + if self.subCommandClasses: + for C in self.subCommandClasses: + c = C(self, stdout=stdout, stderr=stderr) + self.subCommands[c.name] = c + if c.aliases: + for alias in c.aliases: + self.aliasedSubCommands[alias] = c + + # create our formatter and add subcommands if we have them + formatter = CommandHelpFormatter() + if self.subCommands: + for name, command in self.subCommands.items(): + formatter.addCommand(name, command.summary or + command.description) + + # expand %command for the bottom usage + usage = self.usage or self.name + if usage.find("%command") > -1: + usage = usage.split("%command")[0] + '[command]' + usages = [usage, ] + + # FIXME: abstract this into getUsage that takes an optional + # parentCommand on where to stop recursing up + # useful for implementing subshells + + # walk the tree up for our usage + c = self.parentCommand + while c: + usage = c.usage or c.name + if usage.find(" %command") > -1: + usage = usage.split(" %command")[0] + usages.append(usage) + c = c.parentCommand + usages.reverse() + usage = " ".join(usages) + + # create our parser + description = self.description or self.summary + self.parser = CommandOptionParser( + usage=usage, description=description, + formatter=formatter) + self.parser.set_stdout(self.stdout) + self.parser.disable_interspersed_args() + + # allow subclasses to add options + self.addOptions() + + def addOptions(self): + """ + Override me to add options to the parser. + """ + pass + + def do(self, args): + """ + Override me to implement the functionality of the command. + """ + pass + + def parse(self, argv): + """ + Parse the given arguments and act on them. + + @rtype: int + @returns: an exit code + """ + self.options, args = self.parser.parse_args(argv) + + # FIXME: make handleOptions not take options, since we store it + # in self.options now + ret = self.handleOptions(self.options) + if ret: + return ret + + # handle pleas for help + if args and args[0] == 'help': + self.debug('Asked for help, args %r' % args) + + # give help on current command if only 'help' is passed + if len(args) == 1: + self.outputHelp() + return 0 + + # complain if we were asked for help on a subcommand, but we don't + # have any + if not self.subCommands: + self.stderr.write('No subcommands defined.') + self.parser.print_usage(file=self.stderr) + self.stderr.write( + "Use --help to get more information about this command.\n") + return 1 + + # rewrite the args the other way around; + # help doap becomes doap help so it gets deferred to the doap + # command + args = [args[1], args[0]] + + + # if we have args that we need to deal with, do it now + # before we start looking for subcommands + self.handleArguments(args) + + # if we don't have subcommands, defer to our do() method + if not self.subCommands: + ret = self.do(args) + + # if everything's fine, we return 0 + if not ret: + ret = 0 + + return ret + + + # if we do have subcommands, defer to them + try: + command = args[0] + except IndexError: + self.parser.print_usage(file=self.stderr) + self.stderr.write( + "Use --help to get a list of commands.\n") + return 1 + + if command in self.subCommands.keys(): + return self.subCommands[command].parse(args[1:]) + + if self.aliasedSubCommands: + if command in self.aliasedSubCommands.keys(): + return self.aliasedSubCommands[command].parse(args[1:]) + + self.stderr.write("Unknown command '%s'.\n" % command) + return 1 + + def outputHelp(self): + """ + Output help information. + """ + self.parser.print_help(file=self.stderr) + + def outputUsage(self): + """ + Output usage information. + Used when the options or arguments were missing or wrong. + """ + self.parser.print_usage(file=self.stderr) + + def handleOptions(self, options): + """ + Handle the parsed options. + """ + pass + + def handleArguments(self, arguments): + """ + Handle the parsed arguments. + """ + pass + + def getRootCommand(self): + """ + Return the top-level command, which is typically the program. + """ + c = self + while c.parentCommand: + c = c.parentCommand + return c -- cgit