Merge remote-tracking branch 'msft_github/master'

* msft_github/master:
  Add delete() and delete_all_by_pattern() methods to DBInterface class (sonic-net#32)
  Add support for deleting table (sonic-net#31)
  Get Vlan Id from BVID object (sonic-net#30)
  add publish interface for DBInterface (sonic-net#29)

Author: zhenggen-xu

src/swsssdk/configdb.py

@@ -238,6 +238,18 @@ def get_table(self, table):
                 pass    #Ignore non table-formated redis entries
         return data
 
+    def delete_table(self, table):
+        """Delete an entire table from config db.
+        Args:
+            table: Table name.
+        """
+        client = self.redis_clients[self.CONFIG_DB]
+        pattern = '{}{}*'.format(table.upper(), self.TABLE_NAME_SEPARATOR)
+        keys = client.keys(pattern)
+        data = {}
+        for key in keys:
+            client.delete(key)
+
     def mod_config(self, data):
         """Write multiple tables into config db.
            Extra entries/fields in the db which are not in the data are kept.

src/swsssdk/interface.py

@@ -254,6 +254,13 @@ def get_redis_client(self, db_name):
         """
         return self.redis_clients[db_name]
 
+    def publish(self, db_name, channel, message):
+        """
+        Publish message via the channel
+        """
+        client  = self.redis_clients[db_name]
+        return client.publish(channel, message)
+
     @blockable
     def keys(self, db_name, pattern='*'):
         """
@@ -314,6 +321,26 @@ def set(self, db_name, _hash, key, val):
         client = self.redis_clients[db_name]
         return client.hset(_hash, key, val)
 
+    @blockable
+    def delete(self, db_name, key):
+        """
+        Delete %key from DB %db_name
+        Parameter %blocking indicates whether to retry in case of failure
+        """
+        client = self.redis_clients[db_name]
+        return client.delete(key)
+
+    @blockable
+    def delete_all_by_pattern(self, db_name, pattern):
+        """
+        Delete all keys which match %pattern from DB %db_name
+        Parameter %blocking indicates whether to retry in case of failure
+        """
+        client = self.redis_clients[db_name]
+        keys = client.keys(pattern)
+        for key in keys:
+            client.delete(key)
+
     def _unavailable_data_handler(self, db_name, data):
         """
         When the queried config is not available in Redis--wait until it is available.

src/swsssdk/port_util.py

@@ -69,3 +69,14 @@ def get_bridge_port_map(db):
 
     return if_br_oid_map
 
+def get_vlan_id_from_bvid(db, bvid):
+    """
+        Get the Vlan Id from Bridge Vlan Object
+    """
+    db.connect('ASIC_DB')
+    vlan_obj = db.keys('ASIC_DB', "ASIC_STATE:SAI_OBJECT_TYPE_VLAN:" + bvid)
+    vlan_entry = db.get_all('ASIC_DB', vlan_obj[0], blocking=True)
+    vlan_id = vlan_entry[b"SAI_VLAN_ATTR_VLAN_ID"]
+
+    return vlan_id
+