Bug: test_bgp_bbr.py check_other_vms doesn't populate results dict, causing test to always pass

[markx-arista]

Is it platform specific

generic

Importance or Severity

HIgh

Description of the bug

#18300 modified the function check_other_vms and doesn't populate results dictionary, and vm_route returned by it is ignored by parallel_run:

     # Check route on other VMs
@@ -378,23 +399,45 @@ def check_other_vms(nbrhosts, setup, route, accepted=True, node=None, results=No
         vm_route['failed'] = False
         vm_route['message'] = 'Checking route {} on {} passed'.format(str(route), node)
         if accepted:
-            if route.prefix not in list(vm_route['vrfs']['default']['bgpRouteEntries'].keys()):
-                vm_route['failed'] = True
-                vm_route['message'] = 'No route for {} found on {}'.format(route.prefix, node)
-            else:
-                tor_route_aspath = vm_route['vrfs']['default']['bgpRouteEntries'][route.prefix]['bgpRoutePaths'][0]\
-                    ['asPathEntry']['asPath']   # noqa:E211
-                # Route path from other VMs: -> DUT(T1) -> TOR1 -> aspath(other T1 -> DUMMY_ASN1)
-                tor_route_aspath_expected = '{} {} {}'.format(dut_asn, tor1_asn, route.aspath)
-                if tor_route_aspath != tor_route_aspath_expected:
+            tor_route_aspath = None
+            if isinstance(nbrhosts[node]['host'], EosHost):
+                if route.prefix not in list(vm_route['vrfs']['default']['bgpRouteEntries'].keys()):
+                    vm_route['failed'] = True
+                    vm_route['message'] = 'No route for {} found on {}'.format(route.prefix, node)
+                else:
+                    tor_route_aspath = vm_route['vrfs']['default']['bgpRouteEntries'][route.prefix]['bgpRoutePaths'][0]\
+                    ['asPathEntry']['asPath']   # noqa E211
+            elif isinstance(nbrhosts[node]['host'], SonicHost):
+                if vm_route and 'paths' in vm_route:
+                    tor_route_aspath = vm_route['paths'][0]['aspath']['string']
+                else:
                     vm_route['failed'] = True
-                    vm_route['message'] = 'On {} expected aspath: {}, actual aspath: {}'\
-                        .format(node, tor_route_aspath_expected, tor_route_aspath)
+                    vm_route['message'] = 'No route for {} found on {}'.format(route.prefix, node)
+            else:
+                vm_route['failed'] = True
+                logging.error('Unknown host type {} for {}'.format(type(nbrhosts[node]['host']), node))
+                return
+
+            # Route path from other VMs: -> DUT(T1) -> TOR1 -> aspath(other T1 -> DUMMY_ASN1)
+            tor_route_aspath_expected = '{} {} {}'.format(dut_asn, tor1_asn, route.aspath)
+            if tor_route_aspath != tor_route_aspath_expected:
+                vm_route['failed'] = True
+                vm_route['message'] = 'On {} expected aspath: {}, actual aspath: {}'\
+                    .format(node, tor_route_aspath_expected, tor_route_aspath)
         else:
-            if route.prefix in list(vm_route['vrfs']['default']['bgpRouteEntries'].keys()):
+            if isinstance(nbrhosts[node]['host'], EosHost):
+                if route.prefix in list(vm_route['vrfs']['default']['bgpRouteEntries'].keys()):
+                    vm_route['failed'] = True
+                    vm_route['message'] = 'No route {} expected on {}'.format(route.prefix, node)
+            elif isinstance(nbrhosts[node]['host'], SonicHost):
+                if vm_route and 'paths' in vm_route:
+                    vm_route['failed'] = True
+                    vm_route['message'] = 'No route {} expected on {}'.format(route.prefix, node)
+            else:
                 vm_route['failed'] = True
-                vm_route['message'] = 'No route {} expected on {}'.format(route.prefix, node)
-        results[node] = vm_route
+                logging.error('Unknown host type {} for {}'.format(type(nbrhosts[node]['host']), node))
+                return
+        return vm_route

The results dict remains empty after parallel_run, and route validation failures are never detected , so the test always passes:

    results = parallel_run(check_other_vms, (nbrhosts, setup, route), {'accepted': accepted},
                           other_vms, timeout=120, concurrent_tasks=6)

    failed_results = {}
    for node, result in list(results.items()):
        if result['failed']:
            failed_results[node] = result

    pytest_assert(not failed_results, 'Checking route {} failed, failed_results: {}'
                  .format(str(route), json.dumps(failed_results, indent=2)))

Steps to Reproduce

Run the test, print results after parallel_run, it will be empty.

Actual Behavior and Expected Behavior

results dictionary shouldn't be empty and check_other_vms should detect route validation failures.

Relevant log output

Output of show version

Attach files (if any)

No response

[markx-arista]

PR available: #22088