[link flap] refactoring continous link flap test

tests/common/devices/sonic.py

@@ -1015,6 +1015,49 @@ def check_bgp_session_nsf(self, neighbor_ip):
                 return True
         return False
 
+    def _parse_route_summary(self, output):
+        """
+        Sample command output:
+Route Source         Routes               FIB  (vrf default)
+kernel               34                   34
+connected            11                   11
+static               1                    0
+ebgp                 6404                 6404
+ibgp                 0                    0
+------
+Totals               6450                 6449
+
+        Sample parsing output:
+        {
+            'kernel' : { 'routes' : 34 , 'FIB' : 34 },
+            ... ...
+            'Totals' : { 'routes' : 6450, 'FIB' : 6449 }
+        }
+        """
+        ret = {}
+        for line in output:
+            tokens = line.split()
+            if len(tokens) > 1:
+                key = tokens[0]
+                val = {}
+                if tokens[1].isdigit():
+                    val['routes'] = tokens[1]
+                    val['FIB'] = tokens[2] if len(tokens) > 2 and tokens[2].isdigit() else None
+                    ret[key] = val
+        return ret
+
+    def get_ip_route_summary(self):
+        """
+        @summary: issue "show ip[v6] route summary" and parse output into dicitionary.
+                  Going forward, this show command should use tabular output so that
+                  we can simply call show_and_parse() function.
+        """
+        ipv4_output = self.shell("show ip route sum")["stdout_lines"]
+        ipv4_summary = self._parse_route_summary(ipv4_output)
+        ipv6_output = self.shell("show ipv6 route sum")["stdout_lines"]
+        ipv6_summary = self._parse_route_summary(ipv6_output)
+        return ipv4_summary, ipv6_summary
+
     def get_dut_iface_mac(self, iface_name):
         """
         Gets the MAC address of specified interface.
@@ -1228,7 +1271,7 @@ def get_extended_minigraph_facts(self, tbinfo, namespace = DEFAULT_NAMESPACE):
         self.update_backend_flag(tbinfo, mg_facts)
 
         return mg_facts
-    
+
     def update_backend_flag(self, tbinfo, mg_facts):
         mg_facts[constants.IS_BACKEND_TOPOLOGY_KEY] = self.assert_topo_is_backend(tbinfo)
 

tests/platform_tests/link_flap/link_flap_utils.py

@@ -181,21 +181,25 @@ def check_orch_cpu_utilization(dut, orch_cpu_threshold):
     return int(float(orch_cpu)) < orch_cpu_threshold
 
 
-def check_bgp_routes(dut, start_time_ip_route_counts, ipv4=False):
+def check_bgp_routes(dut, start_time_ipv4_route_counts, start_time_ipv6_route_counts):
     """
-    Make Sure all ip routes are relearned with jitter of ~5
+    Make Sure all ip routes are relearned with jitter of ~MAX_DIFF
 
     Args:
         dut: DUT host object
-        start_time_ip_route_counts: IP route counts at start
-        ipv4: Version of IP
-    """
-    if ipv4:
-        end_time_ip_route_counts = dut.shell("show ip route summary | grep Total | awk '{print $2}'")["stdout"]
-        logger.info("IPv4 routes at end: %s", end_time_ip_route_counts)
-    else:
-        end_time_ip_route_counts = dut.shell("show ipv6 route summary | grep Total | awk '{print $2}'")["stdout"]
-        logger.info("IPv6 routes at end: %s", end_time_ip_route_counts)
-
-    incr_ip_route_counts = abs(int(float(start_time_ip_route_counts)) - int(float(end_time_ip_route_counts)))
-    return incr_ip_route_counts < 5
+        start_time_ipv4_route_counts: IPv4 route counts at start
+        start_time_ipv6_route_counts: IPv6 route counts at start
+    """
+    MAX_DIFF = 5
+
+    sumv4, sumv6 = dut.get_ip_route_summary()
+    totalsv4 = sumv4.get('Totals', {})
+    totalsv6 = sumv6.get('Totals', {})
+    routesv4 = totalsv4.get('routes', 0)
+    routesv6 = totalsv6.get('routes', 0)
+    logger.info("IPv4 routes: start {} end {}, summary {}".format(start_time_ipv4_route_counts, routesv4, sumv4))
+    logger.info("IPv6 routes: start {} end {}, summary {}".format(start_time_ipv6_route_counts, routesv6, sumv6))
+
+    incr_ipv4_route_counts = abs(int(float(start_time_ipv4_route_counts)) - int(float(routesv4)))
+    incr_ipv6_route_counts = abs(int(float(start_time_ipv6_route_counts)) - int(float(routesv6)))
+    return incr_ipv4_route_counts < MAX_DIFF and incr_ipv6_route_counts < MAX_DIFF

tests/platform_tests/link_flap/test_cont_link_flap.py

@@ -53,12 +53,13 @@ def test_cont_link_flap(self, request, duthosts, enum_rand_one_per_hwsku_fronten
         logging.info("Redis Memory: %s M", start_time_redis_memory)
 
         # Record ipv4 route counts at start
-        start_time_ipv4_route_counts = duthost.shell("show ip route summary | grep Total | awk '{print $2}'")["stdout"]
-        logging.info("IPv4 routes at start: %s", start_time_ipv4_route_counts)
-
-        # Record ipv6 route counts at start
-        start_time_ipv6_route_counts = duthost.shell("show ipv6 route summary | grep Total | awk '{print $2}'")["stdout"]
-        logging.info("IPv6 routes at start %s", start_time_ipv6_route_counts)
+        sumv4, sumv6 = duthost.get_ip_route_summary()
+        totalsv4 = sumv4.get('Totals', {})
+        totalsv6 = sumv6.get('Totals', {})
+        start_time_ipv4_route_counts = totalsv4.get('routes', 0)
+        start_time_ipv6_route_counts = totalsv6.get('routes', 0)
+        logging.info("IPv4 routes: start {}, summary {}".format(start_time_ipv4_route_counts, sumv4))
+        logging.info("IPv6 routes: start {}, summary {}".format(start_time_ipv6_route_counts, sumv6))
 
         # Make Sure Orch CPU < orch_cpu_threshold before starting test.
         logging.info("Make Sure orchagent CPU utilization is less that %d before link flap", orch_cpu_threshold)
@@ -81,13 +82,10 @@ def test_cont_link_flap(self, request, duthosts, enum_rand_one_per_hwsku_fronten
             for dut_port, fanout, fanout_port in candidates:
                 toggle_one_link(duthost, dut_port, fanout, fanout_port, watch=True)
 
-        # Make Sure all ipv4 routes are relearned with jitter of ~5
-        logging.info("IPv4 routes at start: %s", start_time_ipv4_route_counts)
-        pytest_assert(wait_until(60, 1, check_bgp_routes, duthost, start_time_ipv4_route_counts, True), "Ipv4 routes are not equal after link flap")
-
-        # Make Sure all ipv6 routes are relearned with jitter of ~5
-        logging.info("IPv6 routes at start: %s", start_time_ipv6_route_counts)
-        pytest_assert(wait_until(60, 1, check_bgp_routes, duthost, start_time_ipv6_route_counts), "Ipv6 routes are not equal after link flap")
+        # Make Sure all ipv4/ipv6 routes are relearned with jitter of ~5
+        if not wait_until(60, 1, check_bgp_routes, duthost, start_time_ipv4_route_counts, start_time_ipv6_route_counts):
+            endv4, endv6 = duthost.get_ip_route_summary()
+            pytest.fail("IP routes are not equal after link flap: before ipv4 {} ipv6 {}, after ipv4 {} ipv6 {}".format(sumv4, sumv6, endv4, endv6))
 
         # Record memory status at end
         memory_output = duthost.shell("show system-memory")["stdout"]