[acl-loader]: Add --table_name option to update full operation (sonic-net#249)

This option enables the ability to only do the full update within
this table, which means that only this table will be cleared and
reinstalled with the new rules from the JSON file.

Signed-off-by: Shu0T1an ChenG <[email protected]>

Author: Shuotian Cheng

acl_loader/main.py

@@ -78,6 +78,7 @@ class AclLoader(object):
     def __init__(self):
         self.yang_acl = None
         self.requested_session = None
+        self.current_table = None
         self.tables_db_info = {}
         self.rules_db_info = {}
         self.rules_info = {}
@@ -146,10 +147,19 @@ def get_session_name(self):
 
         return None
 
+    def set_table_name(self, table_name):
+        """
+        Set table name to restrict the table to be modified
+        :param table_name: Table name
+        :return:
+        """
+        self.current_table = table_name
+
     def set_session_name(self, session_name):
         """
-        Set session name to se used in ACL rule action.
+        Set session name to be used in ACL rule action
         :param session_name: Mirror session name
+        :return:
         """
         if session_name not in self.get_sessions_db_info():
             raise AclLoaderException("Session %s does not exist" % session_name)
@@ -356,6 +366,9 @@ def convert_rules(self):
                 warning("%s table does not exist" % (table_name))
                 continue
 
+            if self.current_table is not None and self.current_table != table_name
+                continue
+
             for acl_entry_name in acl_set.acl_entries.acl_entry:
                 acl_entry = acl_set.acl_entries.acl_entry[acl_entry_name]
                 try:
@@ -370,11 +383,14 @@ def convert_rules(self):
     def full_update(self):
         """
         Perform full update of ACL rules configuration. All existing rules
-        will be removed. New rules loaded from file will be installed.
+        will be removed. New rules loaded from file will be installed. If
+        the current_table is not empty, only rules within that table will
+        be removed and new rules in that table will be installed.
         :return:
         """
         for key in self.rules_db_info.keys():
-            self.configdb.mod_entry(self.ACL_RULE, key, None)
+            if self.current_table is None or self.current_table == key[0]:
+               self.configdb.mod_entry(self.ACL_RULE, key, None)
 
         self.configdb.mod_config({self.ACL_RULE: self.rules_info})
 
@@ -593,15 +609,20 @@ def update(ctx):
 
 @update.command()
 @click.argument('filename', type=click.Path(exists=True))
+@click.option('--table_name', type=click.STRING, required=False)
 @click.option('--session_name', type=click.STRING, required=False)
 @click.option('--max_priority', type=click.INT, required=False)
 @click.pass_context
-def full(ctx, filename, session_name, max_priority):
+def full(ctx, filename, table_name, session_name, max_priority):
     """
     Full update of ACL rules configuration.
+    If a table_name is provided, the operation will be restricted in the specified table.
     """
     acl_loader = ctx.obj["acl_loader"]
 
+    if table_name:
+        acl_loader.set_table_name(table_name)
+
     if session_name:
         acl_loader.set_session_name(session_name)