""" The base Command class. All commands in Evennia inherit from the 'Command' class in this module. """ import re from src.locks.lockhandler import LockHandler from src.utils.utils import is_iter, fill, lazy_property def _init_command(mcs, **kwargs): """ Helper command. Makes sure all data are stored as lowercase and do checking on all properties that should be in list form. Sets up locks to be more forgiving. This is used both by the metaclass and (optionally) at instantiation time. If kwargs are given, these are set as instance-specific properties on the command. """ for i in range(len(kwargs)): # used for dynamic creation of commands key, value = kwargs.popitem() setattr(mcs, key, value) mcs.key = mcs.key.lower() if mcs.aliases and not is_iter(mcs.aliases): try: mcs.aliases = [str(alias).strip().lower() for alias in mcs.aliases.split(',')] except Exception: mcs.aliases = [] mcs.aliases = list(set(alias for alias in mcs.aliases if alias and alias != mcs.key)) # optimization - a set is much faster to match against than a list mcs._matchset = set([mcs.key] + mcs.aliases) # optimization for looping over keys+aliases mcs._keyaliases = tuple(mcs._matchset) # by default we don't save the command between runs if not hasattr(mcs, "save_for_next"): mcs.save_for_next = False # pre-process locks as defined in class definition temp = [] if hasattr(mcs, 'permissions'): mcs.locks = mcs.permissions if not hasattr(mcs, 'locks'): # default if one forgets to define completely mcs.locks = "cmd:all()" if not "cmd:" in mcs.locks: mcs.locks = "cmd:all();" + mcs.locks for lockstring in mcs.locks.split(';'): if lockstring and not ':' in lockstring: lockstring = "cmd:%s" % lockstring temp.append(lockstring) mcs.lock_storage = ";".join(temp) if hasattr(mcs, 'arg_regex') and isinstance(mcs.arg_regex, basestring): mcs.arg_regex = re.compile(r"%s" % mcs.arg_regex, re.I) if not hasattr(mcs, "auto_help"): mcs.auto_help = True if not hasattr(mcs, 'is_exit'): mcs.is_exit = False if not hasattr(mcs, "help_category"): mcs.help_category = "general" mcs.help_category = mcs.help_category.lower() class CommandMeta(type): """ The metaclass cleans up all properties on the class """ def __init__(mcs, *args, **kwargs): _init_command(mcs, **kwargs) super(CommandMeta, mcs).__init__(*args, **kwargs) # The Command class is the basic unit of an Evennia command; when # defining new commands, the admin subclass this class and # define their own parser method to handle the input. The # advantage of this is inheritage; commands that have similar # structure can parse the input string the same way, minimizing # parsing errors. class Command(object): """ Base command Usage: command [args] This is the base command class. Inherit from this to create new commands. The cmdhandler makes the following variables available to the command methods (so you can always assume them to be there): self.caller - the game object calling the command self.cmdstring - the command name used to trigger this command (allows you to know which alias was used, for example) cmd.args - everything supplied to the command following the cmdstring (this is usually what is parsed in self.parse()) cmd.cmdset - the cmdset from which this command was matched (useful only seldomly, notably for help-type commands, to create dynamic help entries and lists) cmd.obj - the object on which this command is defined. If a default command, this is usually the same as caller. The following class properties can/should be defined on your child class: key - identifier for command (e.g. "look") aliases - (optional) list of aliases (e.g. ["l", "loo"]) locks - lock string (default is "cmd:all()") help_category - how to organize this help entry in help system (default is "General") auto_help - defaults to True. Allows for turning off auto-help generation arg_regex - (optional) raw string regex defining how the argument part of the command should look in order to match for this command (e.g. must it be a space between cmdname and arg?) (Note that if auto_help is on, this initial string is also used by the system to create the help entry for the command, so it's a good idea to format it similar to this one) """ # Tie our metaclass, for some convenience cleanup __metaclass__ = CommandMeta # the main way to call this command (e.g. 'look') key = "command" # alternative ways to call the command (e.g. 'l', 'glance', 'examine') aliases = [] # a list of lock definitions on the form # cmd:[NOT] func(args) [ AND|OR][ NOT] func2(args) locks = "" # used by the help system to group commands in lists. help_category = "general" # This allows to turn off auto-help entry creation for individual commands. auto_help = True # optimization for quickly separating exit-commands from normal commands is_exit = False # define the command not only by key but by the regex form of its arguments arg_regex = None # auto-set (by Evennia on command instantiation) are: # obj - which object this command is defined on # sessid - which session-id (if any) is responsible for triggering this command def __init__(self, **kwargs): """the lockhandler works the same as for objects. optional kwargs will be set as properties on the Command at runtime, overloading evential same-named class properties.""" if kwargs: _init_command(self, **kwargs) @lazy_property def lockhandler(self): return LockHandler(self) def __str__(self): "Print the command" return self.key def __eq__(self, cmd): """ Compare two command instances to each other by matching their key and aliases. input can be either a cmd object or the name of a command. """ try: # first assume input is a command (the most common case) return cmd.key in self._matchset except AttributeError: # probably got a string return cmd in self._matchset def __ne__(self, cmd): """ The logical negation of __eq__. Since this is one of the most called methods in Evennia (along with __eq__) we do some code-duplication here rather than issuing a method-lookup to __eq__. """ try: return not cmd.key in self._matcheset except AttributeError: return not cmd in self._matchset def __contains__(self, query): """ This implements searches like 'if query in cmd'. It's a fuzzy matching used by the help system, returning True if query can be found as a substring of the commands key or its aliases. query (str) - query to match against. Should be lower case. """ return any(query in keyalias for keyalias in self._keyaliases) def match(self, cmdname): """ This is called by the system when searching the available commands, in order to determine if this is the one we wanted. cmdname was previously extracted from the raw string by the system. cmdname (str) is always lowercase when reaching this point. """ return cmdname in self._matchset def access(self, srcobj, access_type="cmd", default=False): """ This hook is called by the cmdhandler to determine if srcobj is allowed to execute this command. It should return a boolean value and is not normally something that need to be changed since it's using the Evennia permission system directly. """ return self.lockhandler.check(srcobj, access_type, default=default) def msg(self, msg="", to_obj=None, from_obj=None, sessid=None, all_sessions=False, **kwargs): """ This is a shortcut instad of calling msg() directly on an object - it will detect if caller is an Object or a Player and also appends self.sessid automatically. msg - text string of message to send to_obj - target object of message. Defaults to self.caller from_obj - source of message. Defaults to to_obj data - optional dictionary of data sessid - supply data only to a unique sessid (normally not used - this is only potentially useful if to_obj is a Player object different from self.caller or self.caller.player) all_sessions (bool) - default is to send only to the session connected to the target object """ from_obj = from_obj or self.caller to_obj = to_obj or from_obj if not sessid: if hasattr(to_obj, "sessid"): # this is the case when to_obj is e.g. a Character toobj_sessions = to_obj.sessid.get() # If to_obj has more than one session MULTISESSION_MODE=3 # we need to send to every session. #(setting it to None, does it) session_tosend = None if len(toobj_sessions) == 1: session_tosend=toobj_sessions[0] sessid = all_sessions and None or session_tosend elif to_obj == self.caller: # this is the case if to_obj is the calling Player sessid = all_sessions and None or self.sessid else: # if to_obj is a different Player, all their sessions # will be notified unless sessid was given specifically sessid = None to_obj.msg(msg, from_obj=from_obj, sessid=sessid, **kwargs) # Common Command hooks def at_pre_cmd(self): """ This hook is called before self.parse() on all commands. If this hook returns anything but False/None, the command sequence is aborted. """ pass def at_post_cmd(self): """ This hook is called after the command has finished executing (after self.func()). """ pass def parse(self): """ Once the cmdhandler has identified this as the command we want, this function is run. If many of your commands have a similar syntax (for example 'cmd arg1 = arg2') you should simply define this once and just let other commands of the same form inherit from this. See the docstring of this module for which object properties are available to use (notably self.args). """ pass def func(self): """ This is the actual executing part of the command. It is called directly after self.parse(). See the docstring of this module for which object properties are available (beyond those set in self.parse()) """ # a simple test command to show the available properties string = "-" * 50 string += "\n{w%s{n - Command variables from evennia:\n" % self.key string += "-" * 50 string += "\nname of cmd (self.key): {w%s{n\n" % self.key string += "cmd aliases (self.aliases): {w%s{n\n" % self.aliases string += "cmd locks (self.locks): {w%s{n\n" % self.locks string += "help category (self.help_category): {w%s{n\n" % self.help_category.capitalize() string += "object calling (self.caller): {w%s{n\n" % self.caller string += "object storing cmdset (self.obj): {w%s{n\n" % self.obj string += "command string given (self.cmdstring): {w%s{n\n" % self.cmdstring # show cmdset.key instead of cmdset to shorten output string += fill("current cmdset (self.cmdset): {w%s{n\n" % (self.cmdset.key if self.cmdset.key else self.cmdset.__class__)) self.caller.msg(string)