diff options
Diffstat (limited to '')
| -rw-r--r-- | Mailman/app/chains.py | 163 |
1 files changed, 105 insertions, 58 deletions
diff --git a/Mailman/app/chains.py b/Mailman/app/chains.py index 8ac9e9ce7..38c7325ab 100644 --- a/Mailman/app/chains.py +++ b/Mailman/app/chains.py @@ -21,9 +21,13 @@ from __future__ import with_statement __all__ = [ 'AcceptChain', + 'Chain', 'DiscardChain', 'HoldChain', + 'Link', 'RejectChain', + 'initialize', + 'process', ] __metaclass__ = type __i18n_templates__ = True @@ -44,7 +48,8 @@ from Mailman.app.moderator import hold_message from Mailman.app.replybot import autorespond_to_sender, can_acknowledge from Mailman.configuration import config from Mailman.i18n import _ -from Mailman.interfaces import IChain, IChainLink, IMutableChain, IPendable +from Mailman.interfaces import ( + IChain, IChainLink, IMutableChain, IPendable, LinkAction) from Mailman.queue import Switchboard log = logging.getLogger('mailman.vette') @@ -59,7 +64,37 @@ class HeldMessagePendable(dict): -class DiscardChain: +class Link: + """A chain link.""" + implements(IChainLink) + + def __init__(self, rule, action=None, chain=None, function=None): + self.rule = rule + self.action = (LinkAction.defer if action is None else action) + self.chain = chain + self.function = function + + + +class TerminalChainBase: + """A base chain that always matches and executes a method. + + The method is called 'process' and must be provided by the subclass. + """ + implements(IChain) + + def __iter__(self): + """See `IChain`.""" + # First, yield a link that always runs the process method. + yield Link('truth', LinkAction.run, function=self.process) + # Now yield a rule that stops all processing. + yield Link('truth', LinkAction.stop) + + def process(self, mlist, msg, msgdata): + raise NotImplementedError + + +class DiscardChain(TerminalChainBase): """Discard a message.""" implements(IChain) @@ -73,7 +108,7 @@ class DiscardChain: -class HoldChain: +class HoldChain(TerminalChainBase): """Hold a message.""" implements(IChain) @@ -199,7 +234,7 @@ also appear in the first line of the body of the reply.""")), -class RejectChain: +class RejectChain(TerminalChainBase): """Reject/bounce a message.""" implements(IChain) @@ -223,7 +258,7 @@ class RejectChain: -class AcceptChain: +class AcceptChain(TerminalChainBase): """Accept the message for posting.""" implements(IChain) @@ -247,15 +282,6 @@ class AcceptChain: -class Link: - """A chain link.""" - implements(IChainLink) - - def __init__(self, rule, jump): - self.rule = rule - self.jump = jump - - class Chain: """Default built-in moderation chain.""" implements(IMutableChain) @@ -276,42 +302,63 @@ class Chain: """See `IMutableChain`.""" self._links = [] - def process(self, mlist, msg, msgdata): - """See `IMutableChain`.""" - msgdata['rule_hits'] = hits = [] - msgdata['rule_misses'] = misses = [] - jump = None + def __iter__(self): + """See `IChain`.""" for link in self._links: - # The None rule always match. - if link.rule is None: - jump = link.jump - break - # If the rule hits, jump to the given chain. - rule = config.rules.get(link.rule) - if rule is None: - elog.error('Rule not found: %s', rule) - elif rule.check(mlist, msg, msgdata): + yield link + + + +def process(start_chain, mlist, msg, msgdata): + """Process the message through a chain. + + :param start_chain: The name of the chain to start the processing with. + :param mlist: the IMailingList for this message. + :param msg: The Message object. + :param msgdata: The message metadata dictionary. + """ + # Find the starting chain. + current_chain = iter(config.chains[start_chain]) + chain_stack = [] + msgdata['rule_hits'] = hits = [] + msgdata['rule_misses'] = misses = [] + while current_chain: + try: + link = current_chain.next() + except StopIteration: + # This chain is exhausted. Pop the last chain on the stack and + # continue. + if len(chain_stack) == 0: + return + current_chain = chain_stack.pop() + continue + # Process this link. + rule = config.rules[link.rule] + if rule.check(mlist, msg, msgdata): + if rule.record: hits.append(link.rule) - # None is a special jump meaning "keep processing this chain". - if link.jump is not None: - jump = link.jump - break + # The rule matched so run its action. + if link.action is LinkAction.jump: + current_chain = iter(config.chains[link.chain]) + elif link.action is LinkAction.detour: + # Push the current chain so that we can return to it when the + # next chain is finished. + chain_stack.append(current_chain) + current_chain = iter(config.chains[link.chain]) + elif link.action is LinkAction.stop: + # Stop all processing. + return + elif link.action is LinkAction.defer: + # Just process the next link in the chain. + pass + elif link.action is LinkAction.run: + link.function(mlist, msg, msgdata) else: - misses.append(link.rule) + raise AssertionError('Unknown link action: %s' % link.action) else: - # We got through the entire chain without a jumping rule match, so - # we really don't know what to do. Rather than raise an - # exception, jump to the discard chain. - log.info('Jumping to the discard chain by default.') - jump = 'discard' - # Find the named chain. - chain = config.chains.get(jump) - if chain is None: - elog.error('Chain not found: %s', chain) - # Well, what now? Nothing much left to do but discard the - # message, which we can do by simply returning. - else: - chain.process(mlist, msg, msgdata) + # The rule did not match; keep going. + if rule.record: + misses.append(link.rule) @@ -324,20 +371,20 @@ def initialize(): config.chains[chain.name] = chain # Set up a couple of other default chains. default = Chain('built-in', _('The built-in moderation chain.')) - default.append_link(Link('approved', 'accept')) - default.append_link(Link('emergency', 'hold')) - default.append_link(Link('loop', 'discard')) + default.append_link(Link('approved', LinkAction.jump, 'accept')) + default.append_link(Link('emergency', LinkAction.jump, 'hold')) + default.append_link(Link('loop', LinkAction.jump, 'discard')) # Do all these before deciding whether to hold the message for moderation. - default.append_link(Link('administrivia', None)) - default.append_link(Link('implicit-dest', None)) - default.append_link(Link('max-recipients', None)) - default.append_link(Link('max-size', None)) - default.append_link(Link('news-moderation', None)) - default.append_link(Link('no-subject', None)) - default.append_link(Link('suspicious', None)) + default.append_link(Link('administrivia', LinkAction.defer)) + default.append_link(Link('implicit-dest', LinkAction.defer)) + default.append_link(Link('max-recipients', LinkAction.defer)) + default.append_link(Link('max-size', LinkAction.defer)) + default.append_link(Link('news-moderation', LinkAction.defer)) + default.append_link(Link('no-subject', LinkAction.defer)) + default.append_link(Link('suspicious-header', LinkAction.defer)) # Now if any of the above hit, jump to the hold chain. - default.append_link(Link('any', 'hold')) + default.append_link(Link('any', LinkAction.jump, 'hold')) # Finally, the builtin chain defaults to acceptance. - default.append_link(Link(None, 'accept')) + default.append_link(Link('truth', LinkAction.jump, 'accept')) # XXX Read chains from the database and initialize them. pass |