Source code for supybot.registry

###
# Copyright (c) 2004-2005, Jeremiah Fincher
# Copyright (c) 2009-2010, James McCoy
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import re
import os
import time
import json
import codecs
import string
import textwrap

from . import utils, i18n, ircutils
from .utils import minisix
_ = i18n.PluginInternationalization()

[docs]def error(s): """Replace me with something better from another module!""" print('***', s)
[docs]def exception(s): """Ditto!""" print('***', s, 'A bad exception.')
[docs]class RegistryException(Exception): pass
[docs]class InvalidRegistryFile(RegistryException): pass
[docs]class InvalidRegistryName(RegistryException): pass
[docs]class InvalidRegistryValue(RegistryException): pass
[docs]class NonExistentRegistryEntry(RegistryException, AttributeError): # If we use hasattr() on a configuration group/value, Python 3 calls # __getattr__ and looks for an AttributeError, so __getattr__ has to # raise an AttributeError if a registry entry does not exist. pass
ENCODING = 'string_escape' if minisix.PY2 else 'unicode_escape' decoder = codecs.getdecoder(ENCODING) encoder = codecs.getencoder(ENCODING) if hasattr(time, 'monotonic'): monotonic_time = time.monotonic else: # fallback for python < 3.3 monotonic_time = time.time _cache = utils.InsensitivePreservingDict() _lastModified = 0
[docs]def open_registry(filename, clear=False): """Initializes the module by loading the registry file into memory.""" global _lastModified if clear: _cache.clear() _fd = open(filename) fd = utils.file.nonCommentNonEmptyLines(_fd) acc = '' slashEnd = re.compile(r'\\*$') for line in fd: line = line.rstrip('\r\n') # XXX There should be some way to determine whether or not we're # starting a new variable or not. As it is, if there's a backslash # at the end of every line in a variable, it won't be read, and # worse, the error will pass silently. # # If the line ends in an odd number of backslashes, then there is a # line-continutation. m = slashEnd.search(line) if m and len(m.group(0)) % 2: acc += line[:-1] continue else: acc += line try: (key, value) = re.split(r'(?<!\\): ', acc, 1) key = key.strip() value = value.strip('\r\n') value = decoder(value)[0] acc = '' except ValueError: raise InvalidRegistryFile('Error unpacking line %r' % acc) _cache[key] = value _lastModified = monotonic_time() _fd.close()
CONF_FILE_HEADER = """ ###### # Although it is technically possible to do so, we do not recommend that # you edit this file with a text editor. # Whenever possible, do it on IRC using the Config plugin, which # checks values you set are valid before writing them to the # configuration. # Moreover, if you edit this file while the bot is running, your # changes may be lost. ###### """ def close(registry, filename, private=True): first = True fd = utils.file.AtomicFile(filename) fd.write(CONF_FILE_HEADER) for (name, value) in registry.getValues(getChildren=True): help = value.help() if help: lines = textwrap.wrap(value._help) for (i, line) in enumerate(lines): lines[i] = '# %s\n' % line lines.insert(0, '###\n') if first: first = False else: lines.insert(0, '\n') if hasattr(value, 'value'): if value._showDefault: lines.append('#\n') try: x = value.__class__(value._default, value._help) except Exception as e: exception('Exception instantiating default for %s:' % value._name) try: lines.append('# Default value: %s\n' % x) except Exception: exception('Exception printing default value of %s:' % value._name) lines.append('###\n') fd.writelines(lines) if hasattr(value, 'value'): # This lets us print help for non-values. try: if private or not value._private: s = value.serialize() else: s = 'CENSORED' fd.write('%s: %s\n' % (name, s)) except Exception: exception('Exception printing value:') fd.close() def isValidRegistryName(name): # Now we can have . and : in names. I'm still gonna call shenanigans on # anyone who tries to have spaces (though technically I can't see any # reason why it wouldn't work). We also reserve all names starting with # underscores for internal use. return len(name.split()) == 1 and not name.startswith('_') def escape(name): name = encoder(name)[0].decode() name = name.replace(':', '\\:') name = name.replace('.', '\\.') return name def unescape(name): name = name.replace('\\.', '.') name = name.replace('\\:', ':') name = decoder(name.encode())[0] return name _splitRe = re.compile(r'(?<!\\)\.') def split(name): return list(map(unescape, _splitRe.split(name))) def join(names): return '.'.join(map(escape, names))
[docs]class Group(object): """A group; it doesn't hold a value unless handled by a subclass.""" __slots__ = ('_help', '_name', '_added', '_children', '_lastModified', '_private', '_supplyDefault', '_orderAlphabetically', '_wasSet') def __init__(self, help='', orderAlphabetically=True, private=False): self._help = utils.str.normalizeWhitespace(help) self._name = 'unset' self._added = [] self._children = utils.InsensitivePreservingDict() self._lastModified = 0 self._private = private self._supplyDefault = False # It should only be true for Value self._orderAlphabetically = orderAlphabetically self._wasSet = True def __call__(self): raise ValueError('Groups have no value.') def __nonExistentEntry(self, attr): s = _('%r is not a valid entry in %r') % (attr, self._name) raise NonExistentRegistryEntry(s) def _makeChild(self, attr, s): raise NotImplementedError( 'Group does not implement _makeChild; only Value does.') def __hasattr__(self, attr): return attr in self._children def __getattr__(self, attr): if attr.startswith('_'): raise AttributeError('%s has no attribute %s' % (self.__class__.__name__, attr)) elif attr in self._children: return self._children[attr] elif self._supplyDefault: return self._makeChild(attr, str(self)) else: self.__nonExistentEntry(attr) def help(self): return i18n.PluginInternationalization().__call__(self._help) def get(self, attr): # Not getattr(self, attr) because some nodes might have groups that # are named the same as their methods. return self.__getattr__(attr) def setName(self, name): #print '***', name self._name = name if name in _cache and self._lastModified < _lastModified: #print '***>', _cache[name] self.set(_cache[name]) if self._supplyDefault: for (k, v) in _cache.items(): if k.startswith(self._name): rest = k[len(self._name)+1:] # +1 is for . parts = split(rest) if len(parts) == 1 and parts[0] == name: try: self._makeChild(name, v) except InvalidRegistryValue: # It's probably supposed to be registered later. pass def register(self, name, node=None): if not isValidRegistryName(name): raise InvalidRegistryName(name) if node is None: node = Group(private=self._private) else: node._private = node._private or self._private # We tried in any number of horrible ways to make it so that # re-registering something would work. It doesn't, plain and simple. # For the longest time, we had an "Is this right?" comment here, but # from experience, we now know that it most definitely *is* right. if name not in self._children: self._children[name] = node self._added.append(name) names = split(self._name) names.append(name) fullname = join(names) node.setName(fullname) else: # We do this in order to reload the help, if it changed. if node._help != '' and node._help != self._children[name]._help: self._children[name]._help = node._help # We do this so the return value from here is at least useful; # otherwise, we're just returning a useless, unattached node # that's simply a waste of space. node = self._children[name] return node def unregister(self, name): try: node = self._children[name] del self._children[name] # We do this because we need to remove case-insensitively. name = name.lower() for elt in reversed(self._added): if elt.lower() == name: self._added.remove(elt) if node._name in _cache: del _cache[node._name] return node except KeyError: self.__nonExistentEntry(name) def rename(self, old, new): node = self.unregister(old) self.register(new, node) def getValues(self, getChildren=False, fullNames=True): L = [] if self._orderAlphabetically: self._added.sort() for name in self._added: node = self._children[name] if hasattr(node, 'value') or hasattr(node, 'help'): if node._wasSet: L.append((node._name, node)) if getChildren: L.extend(node.getValues(getChildren, fullNames)) if not fullNames: L = [(split(s)[-1], node) for (s, node) in L] return L
class _NoValueGiven: # Special value for Value.error() pass
[docs]class Value(Group): """Invalid registry value. If you're getting this message, report it, because we forgot to put a proper help string here.""" __slots__ = ('__parent', '_default', '_showDefault', '_help', '_callbacks', 'value', '_networkValue', '_channelValue', '_opSettable') def __init__(self, default, help, setDefault=True, showDefault=True, **kwargs): self.__parent = super(Value, self) self.__parent.__init__(help, **kwargs) self._default = default self._showDefault = showDefault self._help = utils.str.normalizeWhitespace(help.strip()) self._callbacks = [] self._networkValue = False self._channelValue = False if setDefault: self.setValue(default) def _makeChild(self, attr, s): v = self.__class__(self._default, self._help) v.set(s) v._wasSet = False if self._networkValue and self._channelValue: # If this is both a network-specific and channel-specific value, # then the child is (only) channel-specific. v._networkValue = False v._channelValue = True v._supplyDefault = True else: # Otherwise, the child is neither network-specific or # channel-specific. v._supplyDefault = False v._help = '' # Clear this so it doesn't print a bazillion times. self.register(attr, v) return v def error(self, value=_NoValueGiven): if hasattr(self, 'errormsg') and value is not _NoValueGiven: try: s = self.errormsg % value except TypeError: s = self.errormsg elif self.__doc__: s = self.__doc__ else: s = """%s has no docstring. If you're getting this message, report it, because we forgot to put a proper help string here."""%\ self._name e = InvalidRegistryValue(utils.str.normalizeWhitespace(s)) e.value = self raise e
[docs] def getSpecific(self, network=None, channel=None, check=True): """Gets the network-specific and/or channel-specific value of this Value. If `check=True` (the default), this will raise an error if `network` (resp. `channel`) is provided but this Value is not network-specific (resp. channel-specific). If `check=False`, then `network` and/or `channel` may be silently ignored. """ if network and not self._networkValue: if check: raise NonExistentRegistryEntry('%s is not network-specific' % self._name) else: network = None if channel and not self._channelValue: if check: raise NonExistentRegistryEntry('%s is not channel-specific' % self._name) else: channel = None # It may seem weird to check channel/network validity here, # but we need to prevent plugins from passing garbage values. # # For example, LinkRelay has an inFilter() function that called # self.registryValue('...', msg.args[0]) no matter the command. This # means that, every time the bot sends a 'PING :<timestamp>' from to # network, LinkRelayed called # self.registryValue('...', '<timestamp>'), which calls this # function. # # We then get the proper group, and do .get('<timestamp>'), which # causes a new variable to be registered. # And if the values have a high cardinality (eg. with timestamps), # this creates *a lot* of values, thereby leaking megabytes of memory # a week. # # Ideally, we would want to not register these variables, but it's # complicated for multiple reasons, including: # # 1. if two plugins .get() them, store them for a little while, then # both set them, we have to take care of it. # 2. if <group>.network.channel is modified, then we need to register # both .channel and .network. (and what if two plugins are doing # this concurrently with different channels?) # 3. we could also have a task run in the upkeep function, but we have # issues again with plugins that keep a reference. # # All in all, this is not ideal, but afaict, this is the least bad # solution. And let's hope no one bruteforces valid channel names. # If you have a better solution, please let us know! # # Also, we're setting them to None instead of raising an error in # order not to break existing plugins. if channel and not ircutils.isChannel(channel): channel = None if network: from . import world # put here to work around circular dependencies if world.getIrc(network) is None: network = None if network and channel: # The complicated case. We want a net+chan specific value, # which may come in three different ways: # # 1. it was set explicitely net+chan # 2. it's inherited from a net specific value (which may itself be # inherited from the base value) # 3. it's inherited from the chan specific value (which is not a # actually a parent in the registry tree, but we need this to # load configuration from old bots). # # The choice between 2 and 3 is done by checking which of the # net-specific and chan-specific values was set explicitely by # a user/admin. In case both were, the net-specific value is used # (there is no particular reason for this, I just think it makes # more sense). network_value = self.get(':' + network) network_channel_value = network_value.get(channel) channel_value = self.get(channel) if network_value._wasSet or network_channel_value._wasSet: # cases 1 and 2 return network_channel_value else: # case 3 return channel_value elif network: return self.get(':' + network) elif channel: return self.get(channel) else: return self
def setName(self, *args): if self._name == 'unset': self._lastModified = 0 self.__parent.setName(*args) self._lastModified = monotonic_time()
[docs] def set(self, s): """Override this with a function to convert a string to whatever type you want, and call self.setValue to set the value.""" self.setValue(s) # redundant as setValue() already sets it, but it avoids really hard # bugs if subclasses mess with _setValue. self._wasSet = True
[docs] def setValue(self, v): """Check conditions on the actual value type here. I.e., if you're a IntegerLessThanOneHundred (all your values must be integers less than 100) convert to an integer in set() and check that the integer is less than 100 in this method. You *must* call this parent method in your own setValue.""" self._setValue(v, inherited=False)
def _setValue(self, v, inherited): """Like setValue, but accepted an extra 'inherited' argument. inherited=True means the value is inherited from the parent, so if the parent gets a new value, this group will get the new value as well.""" self._lastModified = monotonic_time() self.value = v if self._supplyDefault: for (name, child) in list(self._children.items()): if not child._wasSet: child._setValue(v, inherited=True) # We call the callback once everything is clean for callback, args, kwargs in self._callbacks: callback(*args, **kwargs) self._wasSet = not inherited
[docs] def context(self, value): """Return a context manager object, which sets this variable to a temporary value, and set the previous value back when exiting the context.""" class Context: def __enter__(self2): self2._old_value = self.value self.setValue(value) def __exit__(self2, exc_type, exc_value, traceback): self.setValue(self2._old_value) return Context()
[docs] def addCallback(self, callback, *args, **kwargs): """Add a callback to the list. A callback is a function that will be called when the value is changed. You can give this function as many extra arguments as you wish, they will be passed to the callback.""" self._callbacks.append((callback, args, kwargs))
[docs] def removeCallback(self, callback): """Remove all occurences of this callbacks from the callback list.""" self._callbacks = [x for x in self._callbacks if x[0] is not callback]
def __str__(self): return repr(self()) def serialize(self): return encoder(str(self))[0].decode() # We tried many, *many* different syntactic methods here, and this one was # simply the best -- not very intrusive, easily overridden by subclasses, # etc. def __call__(self): if _lastModified > self._lastModified: if self._name in _cache: self.set(_cache[self._name]) return self.value
[docs]class Boolean(Value): """Value must be either True or False (or On or Off).""" __slots__ = () errormsg = _('Value must be either True or False (or On or Off), not %r.')
[docs] def set(self, s): try: v = utils.str.toBool(s) except ValueError: if s.strip().lower() == 'toggle': v = not self.value else: self.error(s) self.setValue(v)
[docs] def setValue(self, v): super(Boolean, self).setValue(bool(v))
[docs]class Integer(Value): """Value must be an integer.""" __slots__ = () errormsg = _('Value must be an integer, not %r.')
[docs] def set(self, s): try: self.setValue(int(s)) except ValueError: self.error(s)
[docs]class NonNegativeInteger(Integer): """Value must be a non-negative integer.""" __slots__ = () errormsg = _('Value must be a non-negative integer, not %r.')
[docs] def setValue(self, v): if v < 0: self.error(v) super(NonNegativeInteger, self).setValue(v)
[docs]class PositiveInteger(NonNegativeInteger): """Value must be positive (non-zero) integer.""" __slots__ = () errormsg = _('Value must be positive (non-zero) integer, not %r.')
[docs] def setValue(self, v): if not v: self.error(v) super(PositiveInteger, self).setValue(v)
[docs]class Float(Value): """Value must be a floating-point number.""" __slots__ = () errormsg = _('Value must be a floating-point number, not %r.')
[docs] def set(self, s): try: self.setValue(float(s)) except ValueError: self.error(s)
[docs] def setValue(self, v): try: super(Float, self).setValue(float(v)) except ValueError: self.error(v)
[docs]class PositiveFloat(Float): """Value must be a floating-point number greater than zero.""" __slots__ = () errormsg = _('Value must be a floating-point number greater than zero, ' 'not %r.')
[docs] def setValue(self, v): if v <= 0: self.error(v) else: super(PositiveFloat, self).setValue(v)
[docs]class Probability(Float): """Value must be a floating point number in the range [0, 1].""" __slots__ = ('__parent',) errormsg = _('Value must be a floating point number in the range [0, 1], ' 'not %r.') def __init__(self, *args, **kwargs): self.__parent = super(Probability, self) self.__parent.__init__(*args, **kwargs)
[docs] def setValue(self, v): if 0 <= v <= 1: self.__parent.setValue(v) else: self.error(v)
[docs]class String(Value): """Value is not a valid Python string.""" __slots__ = () errormsg = _('Value should be a valid Python string, not %r.')
[docs] def set(self, s): v = s if not v: v = '""' elif v[0] != v[-1] or v[0] not in '\'"': v = repr(v) try: v = utils.safeEval(v) if not isinstance(v, minisix.string_types): raise ValueError self.setValue(v) except ValueError: # This catches utils.safeEval(s) errors too. self.error(s)
_printable = string.printable[:-4] def _needsQuoting(self, s): return any([x not in self._printable for x in s]) and s.strip() != s def __str__(self): s = self.value if self._needsQuoting(s): s = repr(s) return s
[docs]class OnlySomeStrings(String): __slots__ = ('__parent', '__dict__') # unfortunately, __dict__ is needed # to set __doc__. validStrings = () def __init__(self, *args, **kwargs): assert self.validStrings, 'There must be some valid strings. ' \ 'This is a bug.' self.__parent = super(OnlySomeStrings, self) self.__parent.__init__(*args, **kwargs) self.__doc__ = format(_('Valid values include %L.'), list(map(repr, self.validStrings))) self.errormsg = format(_('Valid values include %L, not %%r.'), list(map(repr, self.validStrings))) def help(self): strings = [s for s in self.validStrings if s] return format('%s Valid strings: %L.', self._help, strings) def normalize(self, s): lowered = s.lower() L = list(map(str.lower, self.validStrings)) try: i = L.index(lowered) except ValueError: return s # This is handled in setValue. return self.validStrings[i]
[docs] def setValue(self, s): v = self.normalize(s) if s in self.validStrings: self.__parent.setValue(v) else: self.error(v)
[docs]class NormalizedString(String): __slots__ = ('__parent') def __init__(self, default, *args, **kwargs): default = self.normalize(default) self.__parent = super(NormalizedString, self) self.__parent.__init__(default, *args, **kwargs) self._showDefault = False def normalize(self, s): return utils.str.normalizeWhitespace(s.strip())
[docs] def set(self, s): s = self.normalize(s) self.__parent.set(s)
[docs] def setValue(self, s): s = self.normalize(s) self.__parent.setValue(s)
def serialize(self): s = self.__parent.serialize() prefixLen = len(self._name) + 2 lines = textwrap.wrap(s, width=76-prefixLen) last = len(lines)-1 for (i, line) in enumerate(lines): if i != 0: line = ' '*prefixLen + line if i != last: line += '\\' lines[i] = line ret = os.linesep.join(lines) return ret
[docs]class StringSurroundedBySpaces(String): __slots__ = ()
[docs] def setValue(self, v): if v and v.lstrip() == v: v= ' ' + v if v.rstrip() == v: v += ' ' super(StringSurroundedBySpaces, self).setValue(v)
[docs]class StringWithSpaceOnRight(String): __slots__ = ()
[docs] def setValue(self, v): if v and v.rstrip() == v: v += ' ' super(StringWithSpaceOnRight, self).setValue(v)
[docs]class Regexp(Value): """Value must be a valid regular expression.""" errormsg = _('Value must be a valid regular expression, not %r.') def __init__(self, default, *args, **kwargs): # We're not supposed to do convertions here, BUT this is needed # when the value is set programmatically because the value # plugins set (a string) is not the same as the one they get # (a compiled pattern object) default = self._convertFromString(default) super().__init__(default, *args, **kwargs) def error(self, e): s = 'Value must be a regexp of the form m/.../ or /.../. %s' % e e = InvalidRegistryValue(s) e.value = self raise e def _convertFromString(self, s): if s: # We need to preserve the original string, as it's shown in # the user interface and the config file. # It might be tempting to set the original string as an # attribute, but doing so would result in inconsistent states # for childs of this variable, should they be reset, or the # value of there parent change. return (s, utils.str.perlReToPythonRe(s)) else: return None
[docs] def set(self, s): try: v = self._convertFromString(s) except ValueError as e: self.error(e) else: super().set(v)
[docs] def setValue(self, v): """Don't call this function directly from plugins, it is subject to change without notice.""" if v is not None and (not isinstance(v, tuple) or len(v) != 2): raise InvalidRegistryValue( 'Can\'t setValue a regexp, there would be an inconsistency ' 'between the regexp and the recorded string value. ' 'Use .set() instead.') super().setValue(v)
def __call__(self): if self.value is None: return None else: return self.value[1] def __str__(self): if self.value is None: return '' else: return self.value[0]
[docs]class SeparatedListOf(Value): __slots__ = () List = list Value = Value sorted = False
[docs] def splitter(self, s): """Override this with a function that takes a string and returns a list of strings.""" raise NotImplementedError
[docs] def joiner(self, L): """Override this to join the internal list for output.""" raise NotImplementedError
[docs] def set(self, s): L = self.splitter(s) for (i, s) in enumerate(L): v = self.Value(s, '') L[i] = v() self.setValue(L)
[docs] def setValue(self, v): super(SeparatedListOf, self).setValue(self.List(v))
def __str__(self): values = self() if self.sorted: values = sorted(values) if values: return self.joiner(values) else: # We must return *something* here, otherwise down along the road we # can run into issues showing users the value if they've disabled # nick prefixes in any of the numerous ways possible. Since the # config parser doesn't care about this space, we'll use it :) return ' '
[docs]class SpaceSeparatedListOf(SeparatedListOf): __slots__ = ()
[docs] def splitter(self, s): return s.split()
joiner = ' '.join
[docs]class SpaceSeparatedListOfStrings(SpaceSeparatedListOf): __slots__ = () Value = String
[docs]class SpaceSeparatedSetOfStrings(SpaceSeparatedListOfStrings): __slots__ = () List = set
[docs]class CommaSeparatedListOfStrings(SeparatedListOf): __slots__ = () Value = String
[docs] def splitter(self, s): return re.split(r'\s*,\s*', s)
joiner = ', '.join
[docs]class CommaSeparatedSetOfStrings(SeparatedListOf): __slots__ = () List = set Value = String
[docs] def splitter(self, s): return re.split(r'\s*,\s*', s)
joiner = ', '.join
[docs]class TemplatedString(String): __slots__ = () requiredTemplates = [] def __init__(self, *args, **kwargs): assert self.requiredTemplates, \ 'There must be some templates. This is a bug.' self.__parent = super(String, self) self.__parent.__init__(*args, **kwargs)
[docs] def setValue(self, v): def hasTemplate(s): return re.search(r'\$%s\b|\${%s}' % (s, s), v) is not None if utils.iter.all(hasTemplate, self.requiredTemplates): self.__parent.setValue(v) else: self.error(v)
[docs]class Json(String): __slots__ = () # Json-serializable data
[docs] def set(self, v): self.setValue(json.loads(v))
[docs] def setValue(self, v): super(Json, self).setValue(json.dumps(v))
def __call__(self): return json.loads(super(Json, self).__call__()) class _Context: def __init__(self, var): self._var = var def __enter__(self): self._dict = self._var() return self._dict def __exit__(self, *args): self._var.setValue(self._dict)
[docs] def editable(self): """Return an editable dict usable within a 'with' statement and committed to the configuration variable at the end.""" return self._Context(self)
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