Cherry-pick PR #27495: Enhance PrefixListMgr to support dynamic prefix list types

src/sonic-bgpcfgd/bgpcfgd/managers_prefix_list.py

@@ -58,8 +58,20 @@ def _is_device_allowed(self, device_type, device_subtype, allowed_list):
     def generate_prefix_list_config(self, prefix_type, data, add):
         type_cfg = PREFIX_TYPE_CONFIG.get(prefix_type)
         if type_cfg is None:
-            log_warn("PrefixListMgr:: Prefix type '%s' is not supported" % prefix_type)
-            return False
+            cmd_parts = ["no"] if not add else []
+            cmd_parts.extend([data["ipv"], "prefix-list", prefix_type])
+            if "seq" in data:
+                cmd_parts.extend(["seq", str(data["seq"])])
+            cmd_parts.extend([data["action"], data["prefix"]])
+            if "ge" in data:
+                cmd_parts.extend(["ge", str(data["ge"])])
+            if "le" in data:
+                cmd_parts.extend(["le", str(data["le"])])
+            cmd = "\n" + " ".join(cmd_parts)
+            self.cfg_mgr.push(cmd)
+            action = "added to" if add else "removed from"
+            log_debug("PrefixListMgr:: Dynamic prefix list %s %s configuration" % (data["prefix"], action))
+            return True
 
         if not self.directory.path_exist("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME, "localhost"):
             log_info("PrefixListMgr:: Device metadata is not ready yet")
@@ -125,7 +137,11 @@ def del_handler(self, key):
             except (netaddr.NotRegisteredError, netaddr.AddrFormatError, netaddr.AddrConversionError):
                 log_warn("PrefixListMgr:: Prefix '%s' format is wrong for prefix list '%s'" % (prefix_str, prefix_type))
                 return True
-            data = {}
+            if PREFIX_TYPE_CONFIG.get(prefix_type) is None:
+                table_data = self.directory.get_slot(self.db_name, self.table_name)
+                data = dict(table_data.get(key, {}))
+            else:
+                data = {}
             data["prefix"] = str(prefix.cidr)
             data["prefixlen"] = prefix.prefixlen
             data["ipv"] = self.get_ip_type(prefix)

src/sonic-bgpcfgd/tests/test_prefix_list.py

@@ -87,10 +87,12 @@ def constructor_with_constants(constants):
     return m
 
 @patch('bgpcfgd.managers_prefix_list.log_warn')
-def test_unsupported_prefix_type(mocked_log_warn):
+def test_dynamic_prefix_type(mocked_log_warn):
     m = constructor_with_constants({})
-    set_handler_test(m, "UNKNOWN_TYPE|10.0.0.0/24", {})
-    mocked_log_warn.assert_called_with("PrefixListMgr:: Prefix type 'UNKNOWN_TYPE' is not supported")
+    set_handler_test(m, "IPV4_DOWNSTREAM_PREFIXES_VNET_Vnet1001|10.0.0.0/24", {"action": "permit"})
+    push_call = m.cfg_mgr.push.call_args[0][0]
+    assert "ip prefix-list IPV4_DOWNSTREAM_PREFIXES_VNET_Vnet1001 permit 10.0.0.0/24" in push_call
+    mocked_log_warn.assert_not_called()
 
 @patch('bgpcfgd.managers_prefix_list.log_warn')
 def test_anchor_prefix_wrong_device(mocked_log_warn):
@@ -158,3 +160,33 @@ def test_suppress_prefix_no_constants_fallback(mocked_log_debug):
     set_handler_test(m, "SUPPRESS_PREFIX|10.0.0.0/24", {})
     push_call = m.cfg_mgr.push.call_args[0][0]
     assert "SUPPRESS_IPV4_PREFIX" in push_call
+
+# test if dynamic prefix-list config with seq/ge/le is generated correctly
+def test_dynamic_prefix_with_seq_ge_le():
+    m = constructor_with_constants({})
+    set_handler_test(
+        m,
+        "Vnet1001|100.64.0.0/10",
+        {"action": "permit", "seq": "5", "ge": "16", "le": "24"}
+    )
+    push_call = m.cfg_mgr.push.call_args[0][0]
+    assert "ip prefix-list Vnet1001 seq 5 permit 100.64.0.0/10 ge 16 le 24" in push_call
+
+# test if dynamic prefix-list delete keeps stored options for exact removal
+def test_dynamic_prefix_delete_uses_stored_options():
+    m = constructor_with_constants({})
+    set_handler_test(
+        m,
+        "Vnet1001|100.64.0.0/10",
+        {"action": "permit", "seq": "5", "ge": "16", "le": "24"}
+    )
+    del_handler_test(m, "Vnet1001|100.64.0.0/10")
+    push_call = m.cfg_mgr.push.call_args[0][0]
+    assert "no ip prefix-list Vnet1001 seq 5 permit 100.64.0.0/10 ge 16 le 24" in push_call
+
+# test if dynamic prefix-list generates ipv6 command correctly
+def test_dynamic_prefix_ipv6():
+    m = constructor_with_constants({})
+    set_handler_test(m, "A_blue|fc00::/64", {"action": "permit"})
+    push_call = m.cfg_mgr.push.call_args[0][0]
+    assert "ipv6 prefix-list A_blue permit fc00::/64" in push_call