Merge pull request #6454 from zclyne/yifan/scheduler-unit-test-port

make healthz/metrics server ports of the scheduler/descheduler unit tests to be detected automatically to avoid flaky test failures

Author: karmada-bot

cmd/descheduler/app/descheduler_test.go

@@ -18,6 +18,7 @@ package app
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 	"testing"
 	"time"
@@ -27,6 +28,7 @@ import (
 
 	"github.com/karmada-io/karmada/cmd/descheduler/app/options"
 	"github.com/karmada-io/karmada/pkg/util/names"
+	testingutil "github.com/karmada-io/karmada/pkg/util/testing"
 )
 
 func TestNewDeschedulerCommand(t *testing.T) {
@@ -66,8 +68,10 @@ func TestDeschedulerCommandFlagParsing(t *testing.T) {
 }
 
 func TestServeHealthzAndMetrics(t *testing.T) {
-	healthAddress := "127.0.0.1:8082"
-	metricsAddress := "127.0.0.1:8083"
+	ports, err := testingutil.GetFreePorts("127.0.0.1", 2)
+	require.NoError(t, err)
+	healthAddress := fmt.Sprintf("127.0.0.1:%d", ports[0])
+	metricsAddress := fmt.Sprintf("127.0.0.1:%d", ports[1])
 
 	go serveHealthzAndMetrics(healthAddress, metricsAddress)
 

cmd/scheduler/app/scheduler_test.go

@@ -18,6 +18,7 @@ package app
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 	"testing"
 	"time"
@@ -27,6 +28,7 @@ import (
 
 	"github.com/karmada-io/karmada/cmd/scheduler/app/options"
 	"github.com/karmada-io/karmada/pkg/util/names"
+	testingutil "github.com/karmada-io/karmada/pkg/util/testing"
 )
 
 func TestNewSchedulerCommand(t *testing.T) {
@@ -66,8 +68,10 @@ func TestSchedulerCommandFlagParsing(t *testing.T) {
 }
 
 func TestServeHealthzAndMetrics(t *testing.T) {
-	healthAddress := "127.0.0.1:8082"
-	metricsAddress := "127.0.0.1:8083"
+	ports, err := testingutil.GetFreePorts("127.0.0.1", 2)
+	require.NoError(t, err)
+	healthAddress := fmt.Sprintf("127.0.0.1:%d", ports[0])
+	metricsAddress := fmt.Sprintf("127.0.0.1:%d", ports[1])
 
 	go serveHealthzAndMetrics(healthAddress, metricsAddress)
 

pkg/util/testing/helpers.go

@@ -21,7 +21,9 @@ import (
 	"crypto/rsa"
 	"crypto/x509"
 	"encoding/pem"
+	"fmt"
 	"math/big"
+	"net"
 	"time"
 )
 
@@ -69,3 +71,37 @@ func GenerateTestCACertificate() (string, string, error) {
 
 	return string(certPEMData), string(privKeyPEMData), nil
 }
+
+// GetFreePorts attempts to find n available TCP ports on the specified host. It
+// returns a slice of allocated port numbers or an error if it fails to acquire
+// them.
+func GetFreePorts(host string, n int) ([]int, error) {
+	ports := make([]int, 0, n)
+	listeners := make([]net.Listener, 0, n)
+
+	// Make sure we close all listeners if there's an error.
+	defer func() {
+		for _, l := range listeners {
+			l.Close()
+		}
+	}()
+
+	for i := 0; i < n; i++ {
+		listener, err := net.Listen("tcp", fmt.Sprintf("%s:0", host))
+		if err != nil {
+			return nil, err
+		}
+		listeners = append(listeners, listener)
+		tcpAddr, ok := listener.Addr().(*net.TCPAddr)
+		if !ok {
+			return nil, fmt.Errorf("listener address is not a *net.TCPAddr")
+		}
+		ports = append(ports, tcpAddr.Port)
+	}
+
+	// At this point we have all ports, so we can close the listeners.
+	for _, l := range listeners {
+		l.Close()
+	}
+	return ports, nil
+}