Add certs secret name read from env (#2685)

* Add certs secret name read from env

* Rename webhookNameEnv to webhookNameEnvKey

* Add test code for certs secret name from env

* Add missing input case to test CertsSecretNameFromEnv

* Change CertsSecretName to SecretName

webhook/env.go

@@ -22,10 +22,14 @@ import (
 	"strconv"
 )
 
-const portEnvKey = "WEBHOOK_PORT"
+const (
+	portEnvKey = "WEBHOOK_PORT"
 
-// Webhook is the name of the override key used inside of the logging config for Webhook Controller.
-const webhookNameEnv = "WEBHOOK_NAME"
+	// Webhook is the name of the override key used inside of the logging config for Webhook Controller.
+	webhookNameEnvKey = "WEBHOOK_NAME"
+
+	secretNameEnvKey = "WEBHOOK_SECRET_NAME"
+)
 
 // PortFromEnv returns the webhook port set by portEnvKey, or default port if env var is not set.
 func PortFromEnv(defaultPort int) int {
@@ -42,7 +46,7 @@ func PortFromEnv(defaultPort int) int {
 }
 
 func NameFromEnv() string {
-	if webhook := os.Getenv(webhookNameEnv); webhook != "" {
+	if webhook := os.Getenv(webhookNameEnvKey); webhook != "" {
 		return webhook
 	}
 
@@ -52,5 +56,13 @@ If this is a process running on Kubernetes, then initialize this variable via:
   env:
   - name: WEBHOOK_NAME
     value: webhook
-`, webhookNameEnv))
+`, webhookNameEnvKey))
+}
+
+func SecretNameFromEnv(defaultSecretName string) string {
+	secret := os.Getenv(secretNameEnvKey)
+	if secret == "" {
+		return defaultSecretName
+	}
+	return secret
 }

webhook/env_test.go

@@ -21,8 +21,10 @@ import (
 )
 
 const (
-	testDefaultPort      = 8888
-	testMissingInputName = "MissingInput" // portEnvKey is not found.
+	testMissingInputName = "MissingInput"
+
+	testDefaultPort       = 8888
+	testDefaultSecretName = "webhook-certs"
 )
 
 type portTest struct {
@@ -39,6 +41,13 @@ type webhookNameTest struct {
 	wantPanic bool
 }
 
+type secretNameTest struct {
+	name      string
+	in        string
+	want      string
+	wantPanic bool
+}
+
 func TestPort(t *testing.T) {
 	tests := []portTest{{
 		name: testMissingInputName,
@@ -102,7 +111,7 @@ func TestWebhookName(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			// webhookNameEnv is unset when testing missing input.
 			if tc.name != testMissingInputName {
-				t.Setenv(webhookNameEnv, tc.in)
+				t.Setenv(webhookNameEnvKey, tc.in)
 			}
 
 			defer func() {
@@ -119,3 +128,39 @@ func TestWebhookName(t *testing.T) {
 		})
 	}
 }
+
+func TestSecretName(t *testing.T) {
+	tests := []secretNameTest{{
+		name: testMissingInputName,
+		want: testDefaultSecretName,
+	}, {
+		name: "EmptyInput",
+		in:   "",
+		want: testDefaultSecretName,
+	}, {
+		name: "ValidInput",
+		in:   "my-webhook-certs",
+		want: "my-webhook-certs",
+	}}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			// secretNameEnvKey is unset when testing missing input.
+			if tc.name != testMissingInputName {
+				t.Setenv(secretNameEnvKey, tc.in)
+			}
+
+			defer func() {
+				if r := recover(); r == nil && tc.wantPanic {
+					t.Error("Did not panic")
+				} else if r != nil && !tc.wantPanic {
+					t.Error("Got unexpected panic")
+				}
+			}()
+
+			if got := SecretNameFromEnv(testDefaultSecretName); got != tc.want {
+				t.Errorf("SecretNameFromEnv = %s, want: %s", got, tc.want)
+			}
+		})
+	}
+}