Do not create right service RI for nat instances

If a service instance is in-network-nat mode, the traffic on the right side
is always routed in the primary RI. The service RI is not used for anything.
However, since all routes from primary RIs will still be copied into it.
With this commit, we won't create the right RI for such instances.

(cherry picked from commit 0db0a71)

Do not set VRF assign rules for right interfaces of nat instances

We are planning not to link service RI with the primary RI of the
right networks of in-network-nat instances. We should also not
set VRF assign rules.

Partial-Bug: 1554175
Closes-Bug: 1562200
(cherry picked from commit 0354c2b)

Change-Id: I3c043fcf8a9b585acac8ea8bcb449ea5c91879d6

src/config/schema-transformer/config_db.py

@@ -317,6 +317,8 @@ def _update_primary_ri_to_service_ri_connection(self, sc, si_name,
             primary_ri = self.get_primary_routing_instance()
             service_ri_name = self.get_service_name(sc.name, si_name)
             service_ri = RoutingInstanceST.get(service_ri_name)
+            if service_ri is None:
+                return
             if (multi_policy_enabled and
                     service_ri_name in primary_ri.connections):
                 primary_ri.delete_connection(service_ri)
@@ -391,8 +393,8 @@ def delete_inactive_service_chains(self, old_scs, new_scs=None):
             #         VNs that are referring to this SC.
             service_chain_list = old_scs[remote_vn_name]
             for service_chain in service_chain_list or []:
-                if new_scs and\
-                   service_chain in (new_scs.get(remote_vn_name) or []):
+                if new_scs and service_chain in (new_scs.get(remote_vn_name)
+                                                 or []):
                     continue
                 if service_chain in (remote_service_chain_list or []):
                     service_chain.destroy()
@@ -2492,11 +2494,21 @@ def _create(self, si_info):
                 service_ri1.obj.add_route_target(rt_obj.obj,
                                                  InstanceTargetType('import'))
                 self._vnc_lib.routing_instance_update(service_ri1.obj)
-            ri_obj = RoutingInstanceST.create(service_name2, vn2_obj, has_pnf)
-            service_ri2 = RoutingInstanceST.locate(service_name2, ri_obj)
-            if service_ri2 is None:
-                self.log_error("service_ri2 is None")
-                return
+
+            mode = si_info[service]['mode']
+            nat_service = (mode == "in-network-nat")
+            transparent = (mode not in ["in-network", "in-network-nat"])
+            self._logger.info("service chain %s: creating %s chain",
+                              self.name, mode)
+
+            if not nat_service:
+                ri_obj = RoutingInstanceST.create(service_name2, vn2_obj, has_pnf)
+                service_ri2 = RoutingInstanceST.locate(service_name2, ri_obj)
+                if service_ri2 is None:
+                    self.log_error("service_ri2 is None")
+                    return
+            else:
+                service_ri2 = None
 
             if first_node:
                 first_node = False
@@ -2505,12 +2517,6 @@ def _create(self, si_info):
                     rt_list.add(vn1_obj.get_route_target())
                 service_ri1.update_route_target_list(rt_add_export=rt_list)
 
-            mode = si_info[service]['mode']
-            nat_service = (mode == "in-network-nat")
-            transparent = (mode not in ["in-network", "in-network-nat"])
-            self._logger.info("service chain %s: creating %s chain",
-                              self.name, mode)
-
             if transparent:
                 v4_address, v6_address = vn1_obj.allocate_service_chain_ip(
                     service_name1)
@@ -2519,7 +2525,7 @@ def _create(self, si_info):
                     return
                 service_ri1.add_service_info(vn2_obj, service, v4_address,
                                              v6_address)
-                if self.direction == "<>":
+                if service_ri2 and self.direction == "<>":
                     service_ri2.add_service_info(vn1_obj, service, v4_address,
                                                  v6_address)
 
@@ -2535,21 +2541,24 @@ def _create(self, si_info):
                 if not result:
                     return
             self._vnc_lib.routing_instance_update(service_ri1.obj)
-            self._vnc_lib.routing_instance_update(service_ri2.obj)
-
-        rt_list = set(vn2_obj.rt_list)
-        if vn2_obj.allow_transit:
-            rt_list.add(vn2_obj.get_route_target())
-        service_ri2.update_route_target_list(rt_add_export=rt_list)
-
-        if not multi_policy_enabled:
-            service_ri2.add_connection(vn2_obj.get_primary_routing_instance())
-        else:
-            # add primary ri's target to service ri
-            rt_obj = RouteTargetST.get(vn2_obj.get_route_target())
-            service_ri2.obj.add_route_target(rt_obj.obj,
-                                             InstanceTargetType('import'))
-            self._vnc_lib.routing_instance_update(service_ri2.obj)
+            if service_ri2:
+                self._vnc_lib.routing_instance_update(service_ri2.obj)
+
+        if service_ri2:
+            rt_list = set(vn2_obj.rt_list)
+            if vn2_obj.allow_transit:
+                rt_list.add(vn2_obj.get_route_target())
+            service_ri2.update_route_target_list(rt_add_export=rt_list)
+
+            if not multi_policy_enabled:
+                service_ri2.add_connection(
+                    vn2_obj.get_primary_routing_instance())
+            else:
+                # add primary ri's target to service ri
+                rt_obj = RouteTargetST.get(vn2_obj.get_route_target())
+                service_ri2.obj.add_route_target(rt_obj.obj,
+                                                 InstanceTargetType('import'))
+                self._vnc_lib.routing_instance_update(service_ri2.obj)
 
         self.created = True
         self.partially_created = False
@@ -3238,8 +3247,10 @@ def recreate_vrf_assign_table(self):
         if vn is None:
             return
         vm_pt = self.get_virtual_machine_or_port_tuple()
-        if not vm_pt or vm_pt.get_service_mode() not in ['in-network',
-                                                         'in-network-nat']:
+        if not vm_pt:
+            return
+        smode = vm_pt.get_service_mode()
+        if smode not in ['in-network', 'in-network-nat']:
             return
 
         vrf_table = VrfAssignTableType()
@@ -3270,7 +3281,12 @@ def recreate_vrf_assign_table(self):
 
         policy_rule_count = 0
         si_name = vm_pt.service_instance
-        for service_chain_list in vn.service_chains.values():
+        if smode == 'in-network-nat' and self.service_interface_type == 'right':
+            vn_service_chains = []
+        else:
+            vn_service_chains = vn.service_chains.values()
+
+        for service_chain_list in vn_service_chains:
             for service_chain in service_chain_list:
                 if not service_chain.created:
                     continue
@@ -3283,10 +3299,9 @@ def recreate_vrf_assign_table(self):
                                                 dst_port=dp,
                                                 protocol=service_chain.protocol)
 
-                        vrf_rule = VrfAssignRuleType(
-                            match_condition=mc,
-                            routing_instance=ri_name,
-                            ignore_acl=True)
+                        vrf_rule = VrfAssignRuleType(match_condition=mc,
+                                                     routing_instance=ri_name,
+                                                     ignore_acl=True)
                         vrf_table.add_vrf_assign_rule(vrf_rule)
                         policy_rule_count += 1
             # end for service_chain