Avoid coupling tests with hardcoded test CA certs (#6086)

* Avoid coupling tests with hardcoded test CA certs

Signed-off-by: Yihao Wang <yesiamyihao@gmail.com>

* Get rid of copied certificate

Signed-off-by: Yihao Wang <yesiamyihao@gmail.com>

---------

Signed-off-by: Yihao Wang <yesiamyihao@gmail.com>

pkg/util/membercluster_client_test.go

@@ -17,7 +17,9 @@ limitations under the License.
 package util
 
 import (
+	"bytes"
 	"context"
+	"encoding/pem"
 	"io"
 	"net/http"
 	"net/http/httptest"
@@ -36,26 +38,31 @@ import (
 	"github.com/karmada-io/karmada/pkg/util/gclient"
 )
 
-// copy from go/src/net/http/internal/testcert/testcert.go
+// Generated by
+//
+//	openssl genrsa 2048 > ca.key
+//	openssl req -new -x509 -nodes -days 365000 -key ca.key -out ca.crt
 var testCA = []byte(`-----BEGIN CERTIFICATE-----
-MIIDSDCCAjCgAwIBAgIQEP/md970HysdBTpuzDOf0DANBgkqhkiG9w0BAQsFADAS
-MRAwDgYDVQQKEwdBY21lIENvMCAXDTcwMDEwMTAwMDAwMFoYDzIwODQwMTI5MTYw
-MDAwWjASMRAwDgYDVQQKEwdBY21lIENvMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8A
-MIIBCgKCAQEAxcl69ROJdxjN+MJZnbFrYxyQooADCsJ6VDkuMyNQIix/Hk15Nk/u
-FyBX1Me++aEpGmY3RIY4fUvELqT/srvAHsTXwVVSttMcY8pcAFmXSqo3x4MuUTG/
-jCX3Vftj0r3EM5M8ImY1rzA/jqTTLJg00rD+DmuDABcqQvoXw/RV8w1yTRi5BPoH
-DFD/AWTt/YgMvk1l2Yq/xI8VbMUIpjBoGXxWsSevQ5i2s1mk9/yZzu0Ysp1tTlzD
-qOPa4ysFjBitdXiwfxjxtv5nXqOCP5rheKO0sWLk0fetMp1OV5JSJMAJw6c2ZMkl
-U2WMqAEpRjdE/vHfIuNg+yGaRRqI07NZRQIDAQABo4GXMIGUMA4GA1UdDwEB/wQE
-AwICpDATBgNVHSUEDDAKBggrBgEFBQcDATAPBgNVHRMBAf8EBTADAQH/MB0GA1Ud
-DgQWBBQR5QIzmacmw78ZI1C4MXw7Q0wJ1jA9BgNVHREENjA0ggtleGFtcGxlLmNv
-bYINKi5leGFtcGxlLmNvbYcEfwAAAYcQAAAAAAAAAAAAAAAAAAAAATANBgkqhkiG
-9w0BAQsFAAOCAQEACrRNgiioUDzxQftd0fwOa6iRRcPampZRDtuaF68yNHoNWbOu
-LUwc05eOWxRq3iABGSk2xg+FXM3DDeW4HhAhCFptq7jbVZ+4Jj6HeJG9mYRatAxR
-Y/dEpa0D0EHhDxxVg6UzKOXB355n0IetGE/aWvyTV9SiDs6QsaC57Q9qq1/mitx5
-2GFBoapol9L5FxCc77bztzK8CpLujkBi25Vk6GAFbl27opLfpyxkM+rX/T6MXCPO
-6/YBacNZ7ff1/57Etg4i5mNA6ubCpuc4Gi9oYqCNNohftr2lkJr7REdDR6OW0lsL
-rF7r4gUnKeC7mYIH1zypY7laskopiLFAfe96Kg==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 -----END CERTIFICATE-----`)
 
 func TestNewClusterScaleClientSet(t *testing.T) {
@@ -458,6 +465,8 @@ func TestNewClusterClientSet_ClientWorks(t *testing.T) {
 	}))
 	defer s.Close()
 
+	testCA := getCACertFromGTestServer(t, s)
+
 	const clusterName = "test"
 	hostClient := fakeclient.NewClientBuilder().WithScheme(gclient.NewSchema()).WithObjects(
 		&clusterv1alpha1.Cluster{
@@ -666,6 +675,8 @@ func TestNewClusterDynamicClientSet_ClientWorks(t *testing.T) {
 	}))
 	defer s.Close()
 
+	testCA := getCACertFromGTestServer(t, s)
+
 	const clusterName = "test"
 	hostClient := fakeclient.NewClientBuilder().WithScheme(gclient.NewSchema()).WithObjects(
 		&clusterv1alpha1.Cluster{
@@ -695,3 +706,14 @@ func TestNewClusterDynamicClientSet_ClientWorks(t *testing.T) {
 
 	assert.Equal(t, want, got)
 }
+
+func getCACertFromGTestServer(t *testing.T, s *httptest.Server) []byte {
+	t.Helper()
+	testCA := new(bytes.Buffer)
+	err := pem.Encode(testCA, &pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: s.Certificate().Raw,
+	})
+	assert.NoError(t, err)
+	return testCA.Bytes()
+}