diff options
Diffstat (limited to 'src/lib/Bcfg2/Server/Plugins/Ldap.py')
| -rw-r--r-- | src/lib/Bcfg2/Server/Plugins/Ldap.py | 324 |
1 files changed, 159 insertions, 165 deletions
diff --git a/src/lib/Bcfg2/Server/Plugins/Ldap.py b/src/lib/Bcfg2/Server/Plugins/Ldap.py index 553ddbc47..66f317c20 100644 --- a/src/lib/Bcfg2/Server/Plugins/Ldap.py +++ b/src/lib/Bcfg2/Server/Plugins/Ldap.py @@ -1,120 +1,132 @@ +""" A plugin to fetch data from a LDAP directory """ + import imp -import logging +import os import sys import time import traceback +import Bcfg2.Options import Bcfg2.Server.Plugin - -logger = logging.getLogger('Bcfg2.Plugins.Ldap') +from Bcfg2.Logger import Debuggable +from Bcfg2.Utils import ClassName, safe_module_name try: import ldap + HAS_LDAP = True except ImportError: - logger.error("Unable to load ldap module. Is python-ldap installed?") - raise ImportError - -# time in seconds between retries after failed LDAP connection -RETRY_DELAY = 5 -# how many times to try reaching the LDAP server if a connection is broken -# at the very minimum, one retry is needed to handle a restarted LDAP daemon -RETRY_COUNT = 3 - -SCOPE_MAP = { - "base": ldap.SCOPE_BASE, - "one": ldap.SCOPE_ONELEVEL, - "sub": ldap.SCOPE_SUBTREE, -} - -LDAP_QUERIES = [] - - -def register_query(query): - LDAP_QUERIES.append(query) + HAS_LDAP = False class ConfigFile(Bcfg2.Server.Plugin.FileBacked): - """ - Config file for the Ldap plugin - - The config file cannot be 'parsed' in the traditional sense as we would - need some serious type checking ugliness to just get the LdapQuery - subclasses. The alternative would be to have the user create a list with - a predefined name that contains all queries. - The approach implemented here is having the user call a registering - decorator that updates a global variable in this module. - """ - def __init__(self, filename): - self.filename = filename - Bcfg2.Server.Plugin.FileBacked.__init__(self, self.filename) - self.fam.AddMonitor(self.filename, self) + """ Config file for the Ldap plugin """ + + def __init__(self, name, core): + Bcfg2.Server.Plugin.FileBacked.__init__(self, name) + self.core = core + self.queries = list() + self.fam.AddMonitor(name, self) def Index(self): - """ - Reregisters the queries in the config file + """ Get the queries from the config file """ + try: + module = imp.load_source(safe_module_name('Ldap', self.name), + self.name) + except: # pylint: disable=W0702 + err = sys.exc_info()[1] + self.logger.error("Ldap: Failed to import %s: %s" % + (self.name, err)) + return + + if not hasattr(module, "__queries__"): + self.logger.error("Ldap: %s has no __queries__ list" % self.name) + return + + self.queries = list() + for query in module.__queries__: + try: + self.queries.append(getattr(module, query)) + except AttributeError: + self.logger.warning( + "Ldap: %s exports %s, but has no such attribute" % + (self.name, query)) - The config will take care of actually registering the queries, - so we just load it once and don't keep it. - """ - global LDAP_QUERIES - LDAP_QUERIES = [] - imp.load_source("ldap_cfg", self.filename) + if self.core.metadata_cache_mode in ['cautious', 'aggressive']: + self.core.metadata_cache.expire() -class Ldap(Bcfg2.Server.Plugin.Plugin, Bcfg2.Server.Plugin.Connector): - """ - The Ldap plugin allows adding data from an LDAP server to your metadata. - """ - name = "Ldap" +class Ldap(Bcfg2.Server.Plugin.Plugin, + Bcfg2.Server.Plugin.ClientRunHooks, + Bcfg2.Server.Plugin.Connector): + """ The Ldap plugin allows adding data from an LDAP server + to your metadata. """ + experimental = True - debug_flag = False + + options = [ + Bcfg2.Options.Option( + cf=('ldap', 'retries'), type=int, default=3, + help='The number of times to retry reaching the ' + 'LDAP server if a connection is broken'), + Bcfg2.Options.Option( + cf=('ldap', 'retry_delay'), type=float, default=5.0, + help='The time in seconds betreen retries')] def __init__(self, core): Bcfg2.Server.Plugin.Plugin.__init__(self, core) Bcfg2.Server.Plugin.Connector.__init__(self) - self.config = ConfigFile(self.data + "/config.py") - def debug_log(self, message, flag=None): - if (flag is None) and self.debug_flag or flag: - self.logger.error(message) + if not HAS_LDAP: + msg = "Python ldap module is required for Ldap plugin" + self.logger.error(msg) + raise Bcfg2.Server.Plugin.PluginInitError(msg) + + self.config = ConfigFile(os.path.join(self.data, 'config.py')) def get_additional_data(self, metadata): query = None try: data = {} - self.debug_log("LdapPlugin debug: found queries " + - str(LDAP_QUERIES)) - for QueryClass in LDAP_QUERIES: - query = QueryClass() + self.debug_log("Found queries %s" % self.config.queries) + for query_class in self.config.queries: + query = query_class() if query.is_applicable(metadata): - self.debug_log("LdapPlugin debug: processing query '" + - query.name + "'") + self.debug_log("Processing query '%s'" % query.name) data[query.name] = query.get_result(metadata) else: - self.debug_log("LdapPlugin debug: query '" + query.name + - "' not applicable to host '" + - metadata.hostname + "'") + self.debug_log("query '%s' not applicable to host '%s'" % + (query.name, metadata.hostname)) return data - except Exception: + except: # pylint: disable=W0702 if hasattr(query, "name"): - logger.error("LdapPlugin error: " + - "Exception during processing of query named '" + - str(query.name) + - "', query results will be empty" + - " and may cause bind failures") - for line in traceback.format_exception(sys.exc_info()[0], - sys.exc_info()[1], - sys.exc_info()[2]): - logger.error("LdapPlugin error: " + - line.replace("\n", "")) + self.logger.error( + "Exception during processing of query named '%s', query " + "results will be empty and may cause bind failures" % + query.name) + for line in traceback.format_exc().split('\n'): + self.logger.error(line) return {} + def start_client_run(self, metadata): + if self.core.metadata_cache_mode == 'aggressive': + self.logger.warning("Ldap is incompatible with aggressive " + "client metadata caching, try 'cautious' " + "or 'initial'") + self.core.metadata_cache.expire(metadata.hostname) + + +class LdapConnection(Debuggable): + """ Connection to an LDAP server. """ + + __scopes__ = { + 'base': ldap.SCOPE_BASE, + 'one': ldap.SCOPE_ONELEVEL, + 'sub': ldap.SCOPE_SUBTREE, + } + + def __init__(self, host="localhost", port=389, binddn=None, + bindpw=None): + Debuggable.__init__(self) -class LdapConnection(object): - """ - Connection to an LDAP server. - """ - def __init__(self, host="localhost", port=389, - binddn=None, bindpw=None): self.host = host self.port = port self.binddn = binddn @@ -122,48 +134,62 @@ class LdapConnection(object): self.conn = None def __del__(self): + """ Disconnection if the instance is destroyed. """ + self.disconnect() + + def disconnect(self): + """ If a connection to an LDAP server is available, disconnect it. """ if self.conn: - self.conn.unbind() + self.conn.unbund() + self.conn = None - def init_conn(self): + def connect(self): + """ Open a connection to the configured LDAP server, and do a simple + bind ff both binddn and bindpw are set. """ + self.disconnect() self.conn = ldap.initialize(self.url) if self.binddn is not None and self.bindpw is not None: self.conn.simple_bind_s(self.binddn, self.bindpw) def run_query(self, query): - result = None - for attempt in range(RETRY_COUNT + 1): - if attempt >= 1: - logger.error("LdapPlugin error: " + - "LDAP server down (retry " + str(attempt) + "/" + - str(RETRY_COUNT) + ")") + """ Connect to the server and execute the query. If the server is + down, wait the configured amount and try to reconnect. + + :param query: The query to execute on the LDAP server. + :type query: Bcfg.Server.Plugins.Ldap.LdapQuery + """ + for attempt in range(Bcfg2.Options.setup.ldap_retries + 1): try: if not self.conn: - self.init_conn() - result = self.conn.search_s( - query.base, - SCOPE_MAP[query.scope], - query.filter.replace("\\", "\\\\"), - query.attrs, - ) - break + self.connect() + + return self.conn.search_s( + query.base, self.__scopes__[query.scope], + query.filter.replace('\\', '\\\\'), query.attrs) + except ldap.SERVER_DOWN: self.conn = None - time.sleep(RETRY_DELAY) - return result + self.logger.error( + "LdapConnection: Server %s down. Retry %d/%d in %.2fs." % + (self.url, attempt + 1, Bcfg2.Options.setup.ldap_retries, + Bcfg2.Options.setup.ldap_retry_delay)) + time.sleep(Bcfg2.Options.setup.ldap_retry_delay) + + return None @property def url(self): - return "ldap://" + self.host + ":" + str(self.port) + """ The URL of the LDAP server. """ + return "ldap://%s:%d" % (self.host, self.port) class LdapQuery(object): - """ - Query referencing an LdapConnection and providing several - methods for query manipulation. - """ + """ Query referencing an LdapConnection and providing several + methods for query manipulation. """ + + #: Name of the Query, used to register it in additional data. + name = ClassName() - name = "unknown" base = "" scope = "sub" filter = "(objectClass=*)" @@ -172,80 +198,48 @@ class LdapQuery(object): result = None def __unicode__(self): - return "LdapQuery:" + self.name + return "LdapQuery: %s" % self.name - def is_applicable(self, metadata): - """ - Overrideable method to determine if the query is to be executed for - the given metadata object. - Defaults to true. - """ - return True + def is_applicable(self, metadata): # pylint: disable=W0613 + """ Check is the query should be executed for a given metadata + object. - def prepare_query(self, metadata): + :param metadata: The client metadata + :type metadata: Bcfg2.Server.Plugins.Metadata.ClientMetadata """ - Overrideable method to alter the query based on metadata. - Defaults to doing nothing. - - In most cases, you will do something like + return True - self.filter = "(cn=" + metadata.hostname + ")" + def prepare_query(self, metadata, **kwargs): # pylint: disable=W0613 + """ Prepares the query based on the client metadata. You can + for example modify the filter based on the client hostname. - here. + :param metadata: The client metadata + :type metadata: Bcfg2.Server.Plugins.Metadata.ClientMetadata """ pass - def process_result(self, metadata): - """ - Overrideable method to post-process the query result. - Defaults to returning the unaltered result. - """ - return self.result - - def get_result(self, metadata): - """ - Method to handle preparing, executing and processing the query. - """ - if isinstance(self.connection, LdapConnection): - self.prepare_query(metadata) - self.result = self.connection.run_query(self) - self.result = self.process_result(metadata) - return self.result - else: - logger.error("LdapPlugin error: " + - "No valid connection defined for query " + str(self)) - return None - - -class LdapSubQuery(LdapQuery): - """ - SubQueries are meant for internal use only and are not added - to the metadata object. They are useful for situations where - you need to run more than one query to obtain some data. - """ - def prepare_query(self, metadata, **kwargs): - """ - Overrideable method to alter the query based on metadata. - Defaults to doing nothing. - """ - pass + def process_result(self, metadata, **kwargs): # pylint: disable=W0613 + """ Post-process the query result. - def process_result(self, metadata, **kwargs): - """ - Overrideable method to post-process the query result. - Defaults to returning the unaltered result. + :param metadata: The client metadata + :type metadata: Bcfg2.Server.Plugins.Metadata.ClientMetadata """ return self.result def get_result(self, metadata, **kwargs): + """ Handle the perparation, execution and processing of the query. + + :param metadata: The client metadata + :type metadata: Bcfg2.Server.Plugins.Metadata.ClientMetadata + :raises: :class:`Bcfg2.Server.Plugin.exceptions.PluginExecutionError` """ - Method to handle preparing, executing and processing the query. - """ - if isinstance(self.connection, LdapConnection): + + if self.connection is not None: self.prepare_query(metadata, **kwargs) self.result = self.connection.run_query(self) - return self.process_result(metadata, **kwargs) + self.result = self.process_result(metadata, **kwargs) else: - logger.error("LdapPlugin error: " + - "No valid connection defined for query " + str(self)) - return None + raise Bcfg2.Server.Plugin.PluginExecutionError( + 'No connection defined for %s' % self.name) + + return self.result |