enh/refac: ldap handle multiple usernames

backend/open_webui/routers/auths.py

@@ -288,13 +288,11 @@ async def ldap_auth(request: Request, response: Response, form_data: LdapForm):
             f"{LDAP_ATTRIBUTE_FOR_MAIL}",
             "cn",
         ]
-
         if ENABLE_LDAP_GROUP_MANAGEMENT:
             search_attributes.append(f"{LDAP_ATTRIBUTE_FOR_GROUPS}")
             log.info(
                 f"LDAP Group Management enabled. Adding {LDAP_ATTRIBUTE_FOR_GROUPS} to search attributes"
             )
-
         log.info(f"LDAP search attributes: {search_attributes}")
 
         search_success = connection_app.search(
@@ -302,15 +300,22 @@ async def ldap_auth(request: Request, response: Response, form_data: LdapForm):
             search_filter=f"(&({LDAP_ATTRIBUTE_FOR_USERNAME}={escape_filter_chars(form_data.user.lower())}){LDAP_SEARCH_FILTERS})",
             attributes=search_attributes,
         )
-
         if not search_success or not connection_app.entries:
             raise HTTPException(400, detail="User not found in the LDAP server")
 
         entry = connection_app.entries[0]
-        username = str(entry[f"{LDAP_ATTRIBUTE_FOR_USERNAME}"]).lower()
+        entry_username = entry[f"{LDAP_ATTRIBUTE_FOR_USERNAME}"].value
         email = entry[
             f"{LDAP_ATTRIBUTE_FOR_MAIL}"
         ].value  # retrieve the Attribute value
+
+        username_list = []  # list of usernames from LDAP attribute
+        if isinstance(entry_username, list):
+            username_list = [str(name).lower() for name in entry_username]
+        else:
+            username_list = [str(entry_username).lower()]
+
+        # TODO: support multiple emails if LDAP returns a list
         if not email:
             raise HTTPException(400, "User does not have a valid email address.")
         elif isinstance(email, str):
@@ -320,13 +325,13 @@ async def ldap_auth(request: Request, response: Response, form_data: LdapForm):
         else:
             email = str(email).lower()
 
-        cn = str(entry["cn"])
+        cn = str(entry["cn"])  # common name
-        user_dn = entry.entry_dn
+        user_dn = entry.entry_dn  # user distinguished name
 
         user_groups = []
         if ENABLE_LDAP_GROUP_MANAGEMENT and LDAP_ATTRIBUTE_FOR_GROUPS in entry:
             group_dns = entry[LDAP_ATTRIBUTE_FOR_GROUPS]
-            log.info(f"LDAP raw group DNs for user {username}: {group_dns}")
+            log.info(f"LDAP raw group DNs for user {username_list}: {group_dns}")
 
             if group_dns:
                 log.info(f"LDAP group_dns original: {group_dns}")
@@ -377,16 +382,16 @@ async def ldap_auth(request: Request, response: Response, form_data: LdapForm):
                         )
 
                 log.info(
-                    f"LDAP groups for user {username}: {user_groups} (total: {len(user_groups)})"
+                    f"LDAP groups for user {username_list}: {user_groups} (total: {len(user_groups)})"
                 )
             else:
-                log.info(f"No groups found for user {username}")
+                log.info(f"No groups found for user {username_list}")
         elif ENABLE_LDAP_GROUP_MANAGEMENT:
             log.warning(
                 f"LDAP Group Management enabled but {LDAP_ATTRIBUTE_FOR_GROUPS} attribute not found in user entry"
             )
 
-        if username == form_data.user.lower():
+        if username_list and form_data.user.lower() in username_list:
             connection_user = Connection(
                 server,
                 user_dn,