[action] [PR:26349] [sonic-bgpcfgd] Add ability to wait on rehydration for additional Loopback IPs during reloads

dockers/docker-fpm-frr/frr/bgpd/templates/internal/additional_loopbacks.conf.j2

@@ -0,0 +1 @@
+Loopback4096

src/sonic-bgpcfgd/bgpcfgd/managers_bgp.py

@@ -97,6 +97,8 @@ def __init__(self, common_objs, db_name, table_name, peer_type, check_neig_meta)
         self.constants = self.common_objs["constants"]
         self.fabric = common_objs['tf']
         self.peer_type = peer_type
+        self.loopbacks = ["Loopback0"]
+        self.post_dependencies_init_complete = False
 
         base_template = "bgpd/templates/" + self.constants["bgp"]["peers"][peer_type]["template_dir"] + "/"
         self.templates = {
@@ -175,23 +177,20 @@ def add_peer(self, vrf, nbr, data):
         :param data: associated data
         :return: True if this adding was successful, False otherwise
         """
-        print_data = vrf, nbr, data
-        bgp_asn = self.directory.get_slot("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME)["localhost"]["bgp_asn"]
-        #
-        lo0_ipv4 = self.get_lo_ipv4("Loopback0|")
-        if (lo0_ipv4 is None and "bgp_router_id"
-            not in self.directory.get_slot("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME)["localhost"]):
-            log_warn("Loopback0 ipv4 address is not presented yet and bgp_router_id not configured")
-            return False
 
-        #
-        if self.peer_type == 'internal':
-            lo4096_ipv4 = self.get_lo_ipv4("Loopback4096|")
-            if (lo4096_ipv4 is None and "bgp_router_id"
+        if not self.post_dependencies_init_complete:
+            self.post_dependencies_init()
+
+        for loopback in self.loopbacks:
+            lo_ipv4 = self.get_lo_ipv4(loopback + "|")
+            if (lo_ipv4 is None and "bgp_router_id"
                 not in self.directory.get_slot("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME)["localhost"]):
-                log_warn("Loopback4096 ipv4 address is not presented yet and bgp_router_id not configured")
+                log_warn(loopback + " ipv4 address is not presented yet and bgp_router_id not configured")
                 return False
 
+        print_data = vrf, nbr, data
+        bgp_asn = self.directory.get_slot("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME)["localhost"]["bgp_asn"]
+
         if "local_addr" not in data:
             log_warn("Peer %s. Missing attribute 'local_addr'" % nbr)
         else:
@@ -213,6 +212,8 @@ def add_peer(self, vrf, nbr, data):
             'CONFIG_DB__LOOPBACK_INTERFACE':{ tuple(key.split('|')) : {} for key in self.directory.get_slot("CONFIG_DB", swsscommon.CFG_LOOPBACK_INTERFACE_TABLE_NAME)
                                                                          if '|' in key }
         }
+
+        lo0_ipv4 = self.get_lo_ipv4("Loopback0|")
         if lo0_ipv4 is not None:
             kwargs['loopback0_ipv4'] = lo0_ipv4
         if self.check_neig_meta:
@@ -241,6 +242,32 @@ def add_peer(self, vrf, nbr, data):
         self.directory.put(self.db_name, self.table_name, vrf + '|' + nbr, data)
         return True
 
+    def post_dependencies_init(self):
+        self.post_dependencies_init_complete = True #Skip retrying template render failures to not impact existing workflow
+        orig_lo_list_len = len(self.loopbacks)
+        base_template = "bgpd/templates/" + self.constants["bgp"]["peers"][self.peer_type]["template_dir"] + "/"
+        if (os.path.exists(self.fabric.env.loader.searchpath[0] + "/" + base_template + "additional_loopbacks.conf.j2")):
+            kwargs = {
+                'CONFIG_DB__DEVICE_METADATA': self.directory.get_slot("CONFIG_DB", swsscommon.CFG_DEVICE_METADATA_TABLE_NAME)       
+            }
+            try:
+                rendered_loopbacks = self.fabric.from_file(base_template + "additional_loopbacks.conf.j2").render(**kwargs)
+            except jinja2.TemplateError as e:
+                msg = "Error in rendering the template " + base_template + "additional_loopbacks.conf.j2"
+                log_err("%s: %s" % (msg, str(e)))
+                return
+
+            for loopback in rendered_loopbacks.splitlines():
+                loopback_name = loopback.strip()
+                if loopback_name and loopback_name not in self.loopbacks:
+                    self.loopbacks.append(loopback_name)
+
+        if len(self.loopbacks) > orig_lo_list_len:
+            log_info("Additional loopbacks acquired for peer %s, loopback list %s" % (self.peer_type, self.loopbacks))
+        else:
+            log_info("No additional loopbacks acquired for peer %s, loopback list %s" % (self.peer_type, self.loopbacks))
+
+
     def update_state_db(self, vrf, nbr, data, op):
         """
         Update the database with the new data
@@ -482,8 +509,8 @@ def apply_op(self, cmd, vrf):
 
     def get_lo_ipv4(self, loopback_str):
         """
-        Extract Loopback0 ipv4 address from the Directory
-        :return: ipv4 address for Loopback0, None if nothing found
+        Extract LoopbackX ipv4 address from the Directory
+        :return: ipv4 address for LoopbackX, None if nothing found
         """
         loopback0_ipv4 = None
         for loopback in self.directory.get_slot("CONFIG_DB", swsscommon.CFG_LOOPBACK_INTERFACE_TABLE_NAME).keys():

src/sonic-bgpcfgd/tests/test_bgp.py

@@ -115,11 +115,13 @@ def test_add_peer_internal():
         res = m.set_handler("30.30.30.1", {'asn': '65200', 'holdtime': '180', 'keepalive': '60', 'local_addr': '30.30.30.30', 'name': 'TOR', 'nhopself': '0', 'rrclient': '0'})
         assert res, "Expect True return value"
 
-def test_add_peer_internal_no_router_id_no_lo4096():
+@patch('bgpcfgd.managers_bgp.log_info')
+def test_add_peer_internal_no_router_id_no_lo4096(mocked_log_info):
     for constant in load_constant_files():
         m = constructor(constant, peer_type="internal")
         res = m.set_handler("30.30.30.1", {'asn': '65200', 'holdtime': '180', 'keepalive': '60', 'local_addr': '30.30.30.30', 'name': 'TOR', 'nhopself': '0', 'rrclient': '0'})
         assert not res, "Expect False return value"
+        mocked_log_info.assert_called_with("Additional loopbacks acquired for peer internal, loopback list ['Loopback0', 'Loopback4096']")
 
 def test_add_peer_internal_router_id():
     for constant in load_constant_files():
@@ -137,11 +139,15 @@ def test_add_peer_router_id():
         res = m.set_handler("30.30.30.1", {'asn': '65200', 'holdtime': '180', 'keepalive': '60', 'local_addr': '30.30.30.30', 'name': 'TOR', 'nhopself': '0', 'rrclient': '0'})
         assert res, "Expect True return value"
 
-def test_add_peer_without_lo_ipv4():
+@patch('bgpcfgd.managers_bgp.log_info')
+@patch('bgpcfgd.managers_bgp.log_warn')
+def test_add_peer_without_lo_ipv4(mocked_log_warn, mocked_log_info):
     for constant in load_constant_files():
         m = constructor(constant, with_lo0_ipv4=False)
         res = m.set_handler("30.30.30.1", {'asn': '65200', 'holdtime': '180', 'keepalive': '60', 'local_addr': '30.30.30.30', 'name': 'TOR', 'nhopself': '0', 'rrclient': '0'})
         assert not res, "Expect False return value"
+        mocked_log_info.assert_called_with("No additional loopbacks acquired for peer general, loopback list ['Loopback0']")
+        mocked_log_warn.assert_called_with("Loopback0 ipv4 address is not presented yet and bgp_router_id not configured")
 
 def test_add_peer_without_lo_ipv4_router_id():
     for constant in load_constant_files():