From c35347887bb3d452d6104b13308d853b3da44b68 Mon Sep 17 00:00:00 2001 From: "Chris St. Pierre" Date: Tue, 8 May 2012 15:09:54 -0400 Subject: modularized Cfg --- src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py | 331 +++++++++++++++++++++++++++ 1 file changed, 331 insertions(+) create mode 100644 src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py (limited to 'src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py') diff --git a/src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py b/src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py new file mode 100644 index 000000000..9bac50e44 --- /dev/null +++ b/src/lib/Bcfg2/Server/Plugins/Cfg/__init__.py @@ -0,0 +1,331 @@ +"""This module implements a config file repository.""" + +import re +import os +import sys +import stat +import pkgutil +import logging +import binascii +import lxml.etree +import Bcfg2.Server.Plugin +from Bcfg2.Bcfg2Py3k import u_str + +logger = logging.getLogger('Bcfg2.Plugins.Cfg') + +PROCESSORS = None + +class CfgBaseFileMatcher(Bcfg2.Server.Plugin.SpecificData): + __extensions__ = [] + __ignore__ = [] + + def __init__(self, fname, spec, encoding): + Bcfg2.Server.Plugin.SpecificData.__init__(self, fname, spec, encoding) + self.encoding = encoding + self.regex = self.__class__.get_regex(fname) + + @classmethod + def get_regex(cls, fname, extensions=None): + if extensions is None: + extensions = cls.__extensions__ + + base_re = '^(?P%s)(|\\.H_(?P\S+?)|.G(?P\d+)_(?P\S+?))' % re.escape(fname) + if extensions: + base_re += '\\.(?P%s)' % '|'.join(extensions) + base_re += '$' + return re.compile(base_re) + + @classmethod + def handles(cls, basename, event): + return (event.filename.startswith(os.path.basename(basename)) and + cls.get_regex(os.path.basename(basename)).match(event.filename)) + + @classmethod + def ignore(cls, basename, event): + return (cls.__ignore__ and + event.filename.startswith(os.path.basename(basename)) and + cls.get_regex(os.path.basename(basename), + extensions=cls.__ignore__).match(event.filename)) + + + def __str__(self): + return "%s(%s)" % (self.__class__.__name__, self.name) + + def match(self, fname): + return self.regex.match(fname) + + +class CfgGenerator(CfgBaseFileMatcher): + def get_data(self, entry, metadata): + return self.data + + +class CfgFilter(CfgBaseFileMatcher): + def modify_data(self, entry, metadata, data): + raise NotImplementedError + + +class CfgInfo(Bcfg2.Server.Plugin.SpecificData): + names = [] + regex = re.compile('^$') + + def __init__(self, path): + self.path = path + self.name = os.path.basename(path) + + @classmethod + def handles(cls, basename, event): + return event.filename in cls.names or cls.regex.match(event.filename) + + @classmethod + def ignore(cls, basename, event): + return False + + def bind_info_to_entry(self, entry, metadata): + raise NotImplementedError + + def _set_info(self, entry, info): + for key, value in list(info.items()): + entry.attrib.__setitem__(key, value) + + def __str__(self): + return "%s(%s)" % (self.__class__.__name__, self.name) + + +class CfgDefaultInfo(CfgInfo): + def __init__(self, defaults): + self.name = '' + self.defaults = defaults + + def handles(self, event): + return False + + def bind_info_to_entry(self, entry, metadata): + self._set_info(entry, self.defaults) + + +class CfgEntrySet(Bcfg2.Server.Plugin.EntrySet): + def __init__(self, basename, path, entry_type, encoding): + Bcfg2.Server.Plugin.EntrySet.__init__(self, basename, path, + entry_type, encoding) + self.specific = None + self.default_info = CfgDefaultInfo(self.metadata) + self.load_processors() + + def load_processors(self): + """ load Cfg file processors. this must be done at run-time, + not at compile-time, or we get a circular import and things + don't work. but finding the right way to do this at runtime + was ... problematic. so here it is, writing to a global + variable. Sorry 'bout that. """ + global PROCESSORS + if PROCESSORS is None: + PROCESSORS = [] + for submodule in pkgutil.walk_packages(path=__path__): + module = getattr(__import__("%s.%s" % + (__name__, + submodule[1])).Server.Plugins.Cfg, + submodule[1]) + proc = getattr(module, submodule[1]) + if set(proc.__mro__).intersection([CfgInfo, CfgFilter, + CfgGenerator]): + PROCESSORS.append(proc) + + def handle_event(self, event): + action = event.code2str() + + for proc in PROCESSORS: + if proc.handles(self.path, event): + self.debug_log("%s handling %s event on %s" % + (proc.__name__, action, event.filename)) + if action in ['exists', 'created']: + self.entry_init(event, proc) + elif event.filename not in self.entries: + logger.warning("Got %s event for unknown file %s" % + (action, event.filename)) + if action == 'changed': + # received a bogus changed event; warn, but + # treat it like a created event + self.entry_init(event, proc) + elif action == 'changed': + self.entries[event.filename].handle_event(event) + elif action == 'deleted': + del self.entries[event.filename] + return + elif proc.ignore(self.path, event): + return + + logger.error("Could not process filename %s; ignoring" % + event.filename) + + def entry_init(self, event, proc): + if CfgBaseFileMatcher in proc.__mro__: + Bcfg2.Server.Plugin.EntrySet.entry_init( + self, event, entry_type=proc, + specific=proc.get_regex(os.path.basename(self.path))) + else: + if event.filename in self.entries: + logger.warn("Got duplicate add for %s" % event.filename) + else: + fpath = os.path.join(self.path, event.filename) + self.entries[event.filename] = proc(fpath) + self.entries[event.filename].handle_event(event) + + def bind_entry(self, entry, metadata): + info_handlers = [] + generators = [] + filters = [] + for ent in self.entries.values(): + if (hasattr(ent, 'specific') and + not ent.specific.matches(metadata)): + continue + if isinstance(ent, CfgInfo): + info_handlers.append(ent) + elif isinstance(ent, CfgGenerator): + generators.append(ent) + elif isinstance(ent, CfgFilter): + filters.append(ent) + + self.default_info.bind_info_to_entry(entry, metadata) + if len(info_handlers) > 1: + logger.error("More than one info supplier found for %s: %s" % + (self.name, info_handlers)) + if len(info_handlers): + info_handlers[0].bind_info_to_entry(entry, metadata) + if entry.tag == 'Path': + entry.set('type', 'file') + + generator = self.best_matching(metadata, generators) + if entry.get('perms').lower() == 'inherit': + # use on-disk permissions + fname = os.path.join(self.path, generator.name) + entry.set('perms', + str(oct(stat.S_IMODE(os.stat(fname).st_mode)))) + try: + data = generator.get_data(entry, metadata) + except: + msg = "Cfg: exception rendering %s with %s: %s" % \ + (entry.get("name"), generator, sys.exc_info()[1]) + logger.error(msg) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + + for fltr in filters: + data = fltr.modify_data(entry, metadata, data) + + if entry.get('encoding') == 'base64': + data = binascii.b2a_base64(data) + else: + try: + data = u_str(data, self.encoding) + except UnicodeDecodeError: + msg = "Failed to decode %s: %s" % (entry.get('name'), + sys.exc_info()[1]) + logger.error(msg) + logger.error("Please verify you are using the proper encoding.") + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + except ValueError: + msg = "Error in specification for %s: %s" % (entry.get('name'), + sys.exc_info()[1]) + logger.error(msg) + logger.error("You need to specify base64 encoding for %s." % + entry.get('name')) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + + if data: + entry.text = data + else: + entry.set('empty', 'true') + + def list_accept_choices(self, entry, metadata): + '''return a list of candidate pull locations''' + generators = [ent for ent in list(self.entries.values()) + if (isinstance(ent, CfgGenerator) and + ent.specific.matches(metadata))] + if not matching: + msg = "No base file found for %s" % entry.get('name') + logger.error(msg) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + + rv = [] + try: + best = self.best_matching(metadata, generators) + rv.append(best.specific) + except: + pass + + if not rv or not rv[0].hostname: + rv.append(Bcfg2.Server.Plugin.Specificity(hostname=metadata.hostname)) + return rv + + def build_filename(self, specific): + bfname = self.path + '/' + self.path.split('/')[-1] + if specific.all: + return bfname + elif specific.group: + return "%s.G%02d_%s" % (bfname, specific.prio, specific.group) + elif specific.hostname: + return "%s.H_%s" % (bfname, specific.hostname) + + def write_update(self, specific, new_entry, log): + if 'text' in new_entry: + name = self.build_filename(specific) + if os.path.exists("%s.genshi" % name): + msg = "Cfg: Unable to pull data for genshi types" + logger.error(msg) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + elif os.path.exists("%s.cheetah" % name): + msg = "Cfg: Unable to pull data for cheetah types" + logger.error(msg) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + try: + etext = new_entry['text'].encode(self.encoding) + except: + msg = "Cfg: Cannot encode content of %s as %s" % (name, + self.encoding) + logger.error(msg) + raise Bcfg2.Server.Plugin.PluginExecutionError(msg) + open(name, 'w').write(etext) + self.debug_log("Wrote file %s" % name, flag=log) + badattr = [attr for attr in ['owner', 'group', 'perms'] + if attr in new_entry] + if badattr: + # check for info files and inform user of their removal + if os.path.exists(self.path + "/:info"): + logger.info("Removing :info file and replacing with " + "info.xml") + os.remove(self.path + "/:info") + if os.path.exists(self.path + "/info"): + logger.info("Removing info file and replacing with " + "info.xml") + os.remove(self.path + "/info") + metadata_updates = {} + metadata_updates.update(self.metadata) + for attr in badattr: + metadata_updates[attr] = new_entry.get(attr) + infoxml = lxml.etree.Element('FileInfo') + infotag = lxml.etree.SubElement(infoxml, 'Info') + [infotag.attrib.__setitem__(attr, metadata_updates[attr]) \ + for attr in metadata_updates] + ofile = open(self.path + "/info.xml", "w") + ofile.write(lxml.etree.tostring(infoxml, pretty_print=True)) + ofile.close() + self.debug_log("Wrote file %s" % (self.path + "/info.xml"), + flag=log) + + +class Cfg(Bcfg2.Server.Plugin.GroupSpool, + Bcfg2.Server.Plugin.PullTarget): + """This generator in the configuration file repository for Bcfg2.""" + name = 'Cfg' + __author__ = 'bcfg-dev@mcs.anl.gov' + es_cls = CfgEntrySet + es_child_cls = Bcfg2.Server.Plugin.SpecificData + + def AcceptChoices(self, entry, metadata): + return self.entries[entry.get('name')].list_accept_choices(entry, + metadata) + + def AcceptPullData(self, specific, new_entry, log): + return self.entries[new_entry.get('name')].write_update(specific, + new_entry, + log) -- cgit v1.2.3-1-g7c22