suppress warnings about k8s env vars

internal/tools/unknown_keys.go

@@ -66,13 +66,32 @@ func checkEnvironmentConfigKeys(defaults map[string]interface{}) {
 			if !strings.HasPrefix(envKey, envPrefix) {
 				continue
 			}
+			// Kubernetes automatically adds some variables which are not used by Centrifugo
+			// itself. We skip warnings about them.
+			if isKubernetesEnvVar(envKey) {
+				continue
+			}
 			if !isKnownEnvKey(defaults, envPrefix, envKey) {
 				log.Warn().Str("key", envKey).Msg("unknown key found in the environment")
 			}
 		}
 	}
 }
 
+var k8sPrefixes = []string{
+	"CENTRIFUGO_PORT_",
+	"CENTRIFUGO_SERVICE_",
+}
+
+func isKubernetesEnvVar(envKey string) bool {
+	for _, k8sPrefix := range k8sPrefixes {
+		if strings.HasPrefix(envKey, k8sPrefix) {
+			return true
+		}
+	}
+	return false
+}
+
 func isKnownEnvKey(defaults map[string]interface{}, envPrefix string, envKey string) bool {
 	for defKey := range defaults {
 		defKeyEnvFormat := envPrefix + strings.ToUpper(strings.ReplaceAll(defKey, ".", "_"))

internal/tools/unknown_keys_test.go

@@ -0,0 +1,23 @@
+package tools
+
+import (
+	"strconv"
+	"testing"
+)
+
+func Test_isKubernetesEnvVar(t *testing.T) {
+	tests := []struct {
+		envKey string
+		want   bool
+	}{
+		{"CENTRIFUGO_SERVICE_PORT_GRPC", true},
+		{"CENTRIFUGO_PORT_8000_TCP", true},
+	}
+	for i, tt := range tests {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			if got := isKubernetesEnvVar(tt.envKey); got != tt.want {
+				t.Errorf("isKubernetesEnvVar() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}