Refactor "clear BGP session" logic from ipspace#2630 (ipspace#2638)

Author: ipspace

netsim/extra/bgp.policy/plugin.py

@@ -159,13 +159,7 @@ def check_attribute_direction(ndata: Box, ngb: Box, topology: Box, attr: str, at
 def apply_config(node: Box, ngb: Box) -> None:
   global _config_name
   api.node_config(node,_config_name)                    # Remember that we have to do extra configuration
-  for af in ('ipv4','ipv6'):                            # ... and add sessions that have to be cleared
-    if af in ngb and '_src_vrf' not in ngb:
-      data.append_to_list(node.bgp,'_session_clear',ngb[af])
-    elif af in ngb and '_src_vrf' in ngb:
-      for vname,vdata in node.vrfs.items():
-        if vname == ngb['_src_vrf']:
-          data.append_to_list(node.vrfs[vname].bgp,'_session_clear',ngb[af])
+  _bgp.clear_bgp_session(node,ngb)
 
 '''
 Apply attributes supported by bgp.policy plugin to a single neighbor

netsim/extra/bgp.session/plugin.py

@@ -2,7 +2,7 @@
 
 from box import Box
 
-from netsim import api, data, modules
+from netsim import api, modules
 from netsim.utils import log
 from netsim.utils import routing as _bgp
 
@@ -34,13 +34,7 @@ def mark_plugin_config(node: Box, ngb: Box) -> None:
   global _config_name
 
   api.node_config(node,_config_name)                  # Remember that we have to do extra configuration
-  for af in ('ipv4','ipv6'):                          # ... and add sessions that have to be cleared
-    if af in ngb and '_src_vrf' not in ngb:
-      data.append_to_list(node.bgp,'_session_clear',ngb[af])
-    elif af in ngb and '_src_vrf' in ngb:
-      for vname,vdata in node.vrfs.items():
-        if vname == ngb['_src_vrf']:
-          data.append_to_list(node.vrfs[vname].bgp,'_session_clear',ngb[af])
+  _bgp.clear_bgp_session(node,ngb)
 
 '''
 Apply attributes supported by bgp.session plugin to a single neighbor

netsim/utils/routing.py

@@ -7,6 +7,7 @@
 
 from box import Box
 
+from .. import data
 from ..augment import devices
 from . import log
 
@@ -68,6 +69,19 @@ def intf_neighbors(node: Box, vrf: bool = True, select: list = ['ibgp','ebgp'])
         if ngb.get('ifindex',None) == intf.ifindex and ngb.type in select:
           yield (intf,ngb)
 
+'''
+Mark a BGP session that needs to be cleared in the configuration template
+'''
+def clear_bgp_session(node: Box, ngb: Box) -> None:
+  for af in log.AF_LIST:                              # Check all relevant address families
+    if af not in ngb:                                 # ... neighbor not using this AF, move on
+      continue
+
+    # Otherwise, add the neighbor address to the global- or VRF bgp._session_clear list
+    #
+    bgp_data = node.bgp if '_src_vrf' not in ngb else node.vrfs[ngb._src_vrf].bgp
+    data.append_to_list(bgp_data,'_session_clear',ngb[af])
+
 '''
 rp_data: iterate over routing protocol instances (global and VRF)
 '''