De-duplicate load balancer health probes

De-duplicate load balancer health probes by collecting them in an index
keyed by their functional characteristics (protocol, port, interval,
count, and path). Two probes with the same functional characteristics
will generate the same key, and only one of the two will ultimately be added.

pkg/provider/azure_loadbalancer.go

@@ -2190,6 +2190,25 @@ func (az *Cloud) buildHealthProbeRulesForPort(annotations map[string]string, por
 	return probe, nil
 }
 
+// probeKey generates a string key containing all functional probe configuration, to allow de-duplication of like probes.
+func probeKey(probe network.Probe) string {
+	var port, interval, number int32
+	var path string
+	if probe.Port != nil {
+		port = *probe.Port
+	}
+	if probe.IntervalInSeconds != nil {
+		interval = *probe.IntervalInSeconds
+	}
+	if probe.NumberOfProbes != nil {
+		number = *probe.NumberOfProbes
+	}
+	if probe.RequestPath != nil {
+		path = *probe.RequestPath
+	}
+	return fmt.Sprintf("%s-%d-%d-%d-%s", probe.Protocol, port, interval, number, path)
+}
+
 // buildLBRules
 // for following sku: basic loadbalancer vs standard load balancer
 // for following scenario: internal vs external
@@ -2201,6 +2220,7 @@ func (az *Cloud) getExpectedLBRules(
 
 	var expectedRules []network.LoadBalancingRule
 	var expectedProbes []network.Probe
+	uniqueProbes := make(map[string]network.Probe)
 
 	// support podPresence health check when External Traffic Policy is local
 	// take precedence over user defined probe configuration
@@ -2221,7 +2241,7 @@ func (az *Cloud) getExpectedLBRules(
 				NumberOfProbes:    to.Int32Ptr(consts.HealthProbeDefaultNumOfProbe),
 			},
 		}
-		expectedProbes = append(expectedProbes, *nodeEndpointHealthprobe)
+		uniqueProbes[probeKey(*nodeEndpointHealthprobe)] = *nodeEndpointHealthprobe
 	}
 
 	// In HA mode, lb forward traffic of all port to backend
@@ -2248,7 +2268,7 @@ func (az *Cloud) getExpectedLBRules(
 					//ignore error because we only need one correct rule
 				}
 				if portprobe != nil {
-					expectedProbes = append(expectedProbes, *portprobe)
+					uniqueProbes[probeKey(*portprobe)] = *portprobe
 					props.Probe = &network.SubResource{
 						ID: to.StringPtr(az.getLoadBalancerProbeID(lbName, az.getLoadBalancerResourceGroup(), *portprobe.Name)),
 					}
@@ -2294,7 +2314,7 @@ func (az *Cloud) getExpectedLBRules(
 					return expectedProbes, expectedRules, err
 				}
 				if portprobe != nil {
-					expectedProbes = append(expectedProbes, *portprobe)
+					uniqueProbes[probeKey(*portprobe)] = *portprobe
 					props.Probe = &network.SubResource{
 						ID: to.StringPtr(az.getLoadBalancerProbeID(lbName, az.getLoadBalancerResourceGroup(), *portprobe.Name)),
 					}
@@ -2316,6 +2336,10 @@ func (az *Cloud) getExpectedLBRules(
 		}
 	}
 
+	for _, probe := range uniqueProbes {
+		expectedProbes = append(expectedProbes, probe)
+	}
+
 	return expectedProbes, expectedRules, nil
 }
 

pkg/provider/azure_loadbalancer_test.go

@@ -2436,6 +2436,14 @@ func TestReconcileLoadBalancerRule(t *testing.T) {
 			expectedRules:  getDefaultTestRules(false),
 			expectedProbes: getTestProbes("Http", "/", to.Int32Ptr(5), to.Int32Ptr(80), to.Int32Ptr(15012), to.Int32Ptr(2)),
 		},
+		{
+			desc: "getExpectedLBRules should not include duplicate probes when overrides would create them",
+			service: getTestService("test1", v1.ProtocolTCP, map[string]string{
+				"service.beta.kubernetes.io/port_8000_health-probe_port": "10080",
+			}, false, 80, 8000),
+			expectedRules:  []network.LoadBalancingRule{getTestRule(false, 80), getTestRule(false, 8000)},
+			expectedProbes: getTestProbes("Tcp", "/", to.Int32Ptr(5), to.Int32Ptr(8000), to.Int32Ptr(10080), to.Int32Ptr(2)),
+		},
 	}
 	rules := getDefaultTestRules(true)
 	rules[0].IdleTimeoutInMinutes = to.Int32Ptr(5)