Feat: Add configurable LDAP group member attribute and single-run mode (#29)

Author: LorenzoGParisiTecnomat

README.md

@@ -37,6 +37,7 @@ For example, a simple user base DN might look something like `OU=users,DC=exampl
 - `LDAP_GROUP_BASE_DN`: Base DN for groups
 - `LDAP_GROUP_FILTER`: LDAP filter to select groups
 - `LDAP_GROUP_NAME_ATTR`: Attribute used to extract group names (default: 'cn')
+- `LDAP_GROUP_MEMBER_ATTR`: Attribute used to extract group members (default: 'member')
 - `LDAP_HOST`: LDAP host
 - `LDAP_PORT`: LDAP port (default: '389')
 - `LDAP_USER_BASE_DN`: Base DN for users
@@ -48,6 +49,7 @@ For example, a simple user base DN might look something like `OU=users,DC=exampl
 - `POSTGRESQL_PORT`: PostgreSQL server port (default: '5432')
 - `POSTGRESQL_USERNAME`: Username of PostgreSQL user
 - `REPEAT_INTERVAL`: How often (in seconds) to wait before attempting to synchronise again (default: '300')
+- `SINGLE_RUN_MODE`: Enables single-run mode. If 'true', the synchronizer performs one sync and exits (e.g., for cronjobs). Otherwise, it runs continuously at `REPEAT_INTERVAL`. (default: 'false')
 
 ## Contributing
 

guacamole_user_sync/ldap/ldap_client.py

@@ -30,11 +30,13 @@ def __init__(
         auto_bind: bool = True,
         bind_dn: str | None = None,
         bind_password: str | None = None,
+        group_member_attribute: str = "member",
     ) -> None:
         self.auto_bind = auto_bind
         self.bind_dn = bind_dn
         self.bind_password = bind_password
         self.server = Server(hostname, get_info=ALL)
+        self.group_member_attribute = group_member_attribute
 
     @staticmethod
     def as_list(ldap_entry: str | list[str] | None) -> list[str]:
@@ -72,10 +74,22 @@ def connect(self) -> Connection:
     def search_groups(self, query: LDAPQuery) -> list[LDAPGroup]:
         output = []
         for entry in self.search(query):
+
+            member_of_attr = getattr(entry, 'memberOf', None)
+            member_of_values = self.as_list(member_of_attr.value if member_of_attr else None)
+
+            member_attr = getattr(entry, self.group_member_attribute, None)
+            member_values = self.as_list(member_attr.value if member_attr else None)
+            
+            if hasattr(entry, self.group_member_attribute):
+                member_values = self.as_list(getattr(entry, self.group_member_attribute).value)
+            else:
+                member_values = []
+
             output.append(
                 LDAPGroup(
-                    member_of=self.as_list(entry.memberOf.value),
-                    member_uid=self.as_list(entry.memberUid.value),
+                    member_of=member_of_values,
+                    member_uid=member_values,
                     name=getattr(entry, query.id_attr).value,
                 ),
             )
@@ -86,12 +100,23 @@ def search_groups(self, query: LDAPQuery) -> list[LDAPGroup]:
     def search_users(self, query: LDAPQuery) -> list[LDAPUser]:
         output = []
         for entry in self.search(query):
+
+            member_of_attr = getattr(entry, 'memberOf', None)
+            member_of_values = self.as_list(member_of_attr.value) if member_of_attr else []
+
+            display_name_attr = getattr(entry, 'displayName', None)
+            display_name_value = display_name_attr.value if display_name_attr else ""
+
+            uid_attr = getattr(entry, 'uid', None)
+            uid_value = uid_attr.value if uid_attr else ""
+
+
             output.append(
                 LDAPUser(
-                    display_name=entry.displayName.value,
-                    member_of=self.as_list(entry.memberOf.value),
+                    display_name=display_name_value,
+                    member_of=member_of_values,
                     name=getattr(entry, query.id_attr).value,
-                    uid=entry.uid.value,
+                    uid=uid_value,
                 ),
             )
             logger.debug("Found LDAP user %s", output[-1])

guacamole_user_sync/postgresql/postgresql_client.py

@@ -1,5 +1,6 @@
 import logging
 import secrets
+import re
 from datetime import UTC, datetime
 
 from sqlalchemy.exc import SQLAlchemyError
@@ -35,6 +36,7 @@ def __init__(
         port: int,
         user_name: str,
         user_password: str,
+        ldap_group_member_attr: str,
     ) -> None:
         self.backend = PostgreSQLBackend(
             connection_details=PostgreSQLConnectionDetails(
@@ -45,7 +47,13 @@ def __init__(
                 user_password=user_password,
             ),
         )
+        self.ldap_group_member_attr = ldap_group_member_attr
 
+    @staticmethod
+    def extract_uid_from_dn(dn: str) -> str | None:
+        match = re.search(r"uid=([^,]+)", dn)
+        return match.group(1) if match else None
+    
     def assign_users_to_groups(
         self,
         groups: list[LDAPGroup],
@@ -94,11 +102,23 @@ def assign_users_to_groups(
                 group.name,
                 len(group.member_uid),
             )
-            for user_uid in group.member_uid:
+            for member_value in group.member_uid:
+                uid_to_match = member_value
+
+                if self.ldap_group_member_attr == "member" or "=" in member_value:
+                    extracted_uid = self.extract_uid_from_dn(member_value)
+                    if extracted_uid:
+                        uid_to_match = extracted_uid
+                    else:
+                        logger.debug(
+                            "Could not extract UID from member value (possibly not a DN or malformed): %s. Using raw value as UID.",
+                            member_value
+                        )
+
                 try:
-                    user = next(filter(lambda u: u.uid == user_uid, users))
+                    user = next(filter(lambda u: u.uid == uid_to_match, users))
                 except StopIteration:
-                    logger.debug("Could not find LDAP user with UID %s", user_uid)
+                    logger.debug("Could not find LDAP user with UID %s (from member value: %s)", uid_to_match, member_value)
                     continue
                 try:
                     user_entity_id = next(
@@ -117,7 +137,7 @@ def assign_users_to_groups(
                 except StopIteration:
                     logger.debug(
                         "Could not find entity ID for LDAP user '%s'",
-                        user_uid,
+                        user.name,
                     )
                     continue
                 # Record user/group associations

synchronise.py

@@ -1,6 +1,7 @@
 #! /usr/bin/env python3
 import logging
 import os
+import sys
 import time
 
 from guacamole_user_sync.ldap import LDAPClient
@@ -25,12 +26,15 @@ def main(  # noqa: PLR0913
     postgresql_port: int,
     postgresql_user_name: str,
     repeat_interval: int,
-) -> None:
+    ldap_group_member_attr: str,
+    single_run_mode: bool = False,
+) -> int:
     # Initialise LDAP resources
     ldap_client = LDAPClient(
         f"{ldap_host}:{ldap_port}",
         bind_dn=ldap_bind_dn,
         bind_password=ldap_bind_password,
+        group_member_attribute=ldap_group_member_attr,
     )
     ldap_group_query = LDAPQuery(
         base_dn=ldap_group_base_dn,
@@ -48,21 +52,34 @@ def main(  # noqa: PLR0913
         port=postgresql_port,
         user_name=postgresql_user_name,
         user_password=postgresql_password,
+        ldap_group_member_attr=ldap_group_member_attr,
     )
 
-    # Loop until terminated
-    while True:
-        # Run synchronisation step
-        synchronise(
+    if single_run_mode:
+        success = synchronise(
             ldap_client=ldap_client,
             ldap_group_query=ldap_group_query,
             ldap_user_query=ldap_user_query,
             postgresql_client=postgresql_client,
+            ldap_group_member_attr=ldap_group_member_attr,
         )
+        return 0 if success else 1
+    else:
+        # Loop until terminated
+        while True:
+            # Run synchronisation step
+            synchronise(
+                ldap_client=ldap_client,
+                ldap_group_query=ldap_group_query,
+                ldap_user_query=ldap_user_query,
+                postgresql_client=postgresql_client,
+                ldap_group_member_attr=ldap_group_member_attr,
+            )
 
-        # Wait before repeating
-        logger.info("Waiting %s seconds.", repeat_interval)
-        time.sleep(repeat_interval)
+            # Wait before repeating
+            logger.info("Waiting %s seconds.", repeat_interval)
+            time.sleep(repeat_interval)
+        return 0
 
 
 def synchronise(
@@ -71,21 +88,24 @@ def synchronise(
     ldap_group_query: LDAPQuery,
     ldap_user_query: LDAPQuery,
     postgresql_client: PostgreSQLClient,
-) -> None:
+    ldap_group_member_attr: str
+) -> bool:
     logger.info("Starting synchronisation.")
     try:
         ldap_groups = ldap_client.search_groups(ldap_group_query)
         ldap_users = ldap_client.search_users(ldap_user_query)
     except LDAPError:
         logger.warning("LDAP server query failed")
-        return
+        return False
 
     try:
         postgresql_client.ensure_schema(SchemaVersion.v1_5_5)
         postgresql_client.update(groups=ldap_groups, users=ldap_users)
     except PostgreSQLError:
         logger.warning("PostgreSQL update failed")
-        return
+        return False
+
+    return True
 
 
 if __name__ == "__main__":
@@ -127,12 +147,13 @@ def synchronise(
     )
     logger = logging.getLogger("guacamole_user_sync")
 
-    main(
+    exit_code = main(
         ldap_bind_dn=os.getenv("LDAP_BIND_DN", None),
         ldap_bind_password=os.getenv("LDAP_BIND_PASSWORD", None),
         ldap_group_base_dn=ldap_group_base_dn,
         ldap_group_filter=ldap_group_filter,
         ldap_group_name_attr=os.getenv("LDAP_GROUP_NAME_ATTR", "cn"),
+        ldap_group_member_attr=os.getenv("LDAP_GROUP_MEMBER_ATTR", "memberUid"),
         ldap_host=ldap_host,
         ldap_port=int(os.getenv("LDAP_PORT", "389")),
         ldap_user_base_dn=ldap_user_base_dn,
@@ -144,4 +165,6 @@ def synchronise(
         postgresql_port=int(os.getenv("POSTGRESQL_PORT", "5432")),
         postgresql_user_name=postgresql_user_name,
         repeat_interval=int(os.getenv("REPEAT_INTERVAL", "300")),
+        single_run_mode=os.getenv("SINGLE_RUN_MODE", "false").lower() == "true",
     )
+    sys.exit(exit_code)