[gen, shared] More work on LDAP.

shared/ldap_connector.py

@@ -0,0 +1,72 @@
+# ------------------------------------------------------------------------------
+try:
+    import ldap
+except ImportError:
+    # For people that do not care about ldap.
+    ldap = None
+
+# ------------------------------------------------------------------------------
+class LdapConnector:
+    '''This class manages the communication with a LDAP server.'''
+    def __init__(self, serverUri, tentatives=5, ssl=False, timeout=5,
+                 tool=None):
+        # The URI of the LDAP server, ie ldap://some.ldap.server:389.
+        self.serverUri = serverUri
+        # The object that will represent the LDAP server
+        self.server = None
+        # The number of trials the connector will at most perform to the LDAP
+        # server, when executing a query in it.
+        self.tentatives = tentatives
+        self.ssl = ssl
+        # The timeout for every query to the LDAP.
+        self.timeout = timeout
+        # A tool from a Appy application can be given and will be used, ie for
+        # logging purpose.
+        self.tool = tool
+
+    def log(self, message, type='info'):
+        '''Logs via a Appy tool if available.'''
+        if self.tool: self.tool.log(message, type=type)
+
+    def connect(self, login, password):
+        '''Connects to the LDAP server using p_login and p_password as
+           credentials. If the connection succeeds, a server object is created
+           in self.server and tuple (True, None) is returned. Else, tuple
+           (False, errorMessage) is returned.'''
+        try:
+            self.server = ldap.initialize(self.serverUri)
+            self.server.simple_bind_s(login, password)
+            return True, None
+        except ldap.LDAPError, le:
+            message = str(le)
+            self.log('%s: connect error with login %s (%s).' % \
+                     (self.serverUri, login, message))
+            return False, message
+
+    def getFilter(self, values):
+        '''Builds and returns a LDAP filter based on p_values, a tuple or list
+           of tuples (name,value).'''
+        return '(&%s)' % ''.join(['(%s=%s)' % (n, v) for n, v in values])
+
+    def search(self, baseDn, scope, filter, attributes=None):
+        '''Performs a query in the LDAP at node p_baseDn, with the given
+           p_scope. p_filter is a LDAP filter that constraints the search. It
+           can be computed from a list of tuples (value, name) by method
+           m_getFilter. p_attributes is the list of attributes that we will
+           retrieve from the LDAP. If None, all attributes will be retrieved.'''
+        if self.ssl: self.server.start_tls_s()
+        try:
+            # Get the LDAP constant corresponding to p_scope.
+            scope = getattr(ldap, 'SCOPE_%s' % scope)
+            # Perform the query.
+            for i in range(self.tentatives):
+                try:
+                    return self.server.search_st(\
+                        baseDn, scope, filterstr=filter, attrlist=attributes,
+                        timeout=self.timeout)
+                except ldap.TIMEOUT:
+                    pass
+        except ldap.LDAPError, le:
+            self.log('LDAP query error %s: %s' % \
+                     (le.__class__.__name__, str(le)))
+# ------------------------------------------------------------------------------