Trident liveness probe should check for ACP only if it is enabled

The purpose of this change is to ensure Trident's liveness probe does not spam logs if ACP is not enabled.

acp/client.go

@@ -55,10 +55,14 @@ func newClient(restAPI REST, acpEnabled bool) TridentACP {
 	return &client{restAPI, acpEnabled}
 }
 
+func (c *client) Enabled() bool {
+	return c.acpEnabled
+}
+
 func (c *client) GetVersion(ctx context.Context) (*version.Version, error) {
 	Logc(ctx).Debug("Getting Trident-ACP version.")
 
-	if !c.acpEnabled {
+	if !c.Enabled() {
 		Logc(ctx).Debug("ACP is not enabled.")
 		return nil, errors.UnsupportedError("ACP is not enabled")
 	}
@@ -83,7 +87,7 @@ func (c *client) GetVersionWithBackoff(ctx context.Context) (*version.Version, e
 	var v *version.Version
 	var err error
 
-	if !c.acpEnabled {
+	if !c.Enabled() {
 		Logc(ctx).Debug("ACP is not enabled.")
 		return nil, errors.UnsupportedError("ACP is not enabled")
 	}
@@ -123,7 +127,7 @@ func (c *client) IsFeatureEnabled(ctx context.Context, feature string) error {
 	fields := LogFields{"feature": feature}
 	Logc(ctx).WithFields(fields).Debug("Checking if feature is enabled.")
 
-	if !c.acpEnabled {
+	if !c.Enabled() {
 		Logc(ctx).WithFields(fields).Warning("Feature requires Trident-ACP to be enabled.")
 		return errors.UnsupportedConfigError("acp is not enabled")
 	}

acp/types.go

@@ -13,6 +13,7 @@ import (
 
 // TridentACP is a set of methods for exposing Trident-ACP REST APIs to Trident.
 type TridentACP interface {
+	Enabled() bool
 	GetVersion(context.Context) (*version.Version, error)
 	GetVersionWithBackoff(context.Context) (*version.Version, error)
 	IsFeatureEnabled(context.Context, string) error

frontend/rest/controller_handlers.go

@@ -271,6 +271,10 @@ func GetVersion(w http.ResponseWriter, r *http.Request) {
 }
 
 func GetACPVersion(ctx context.Context) string {
+	if !acp.API().Enabled() {
+		return ""
+	}
+
 	version, err := acp.API().GetVersion(ctx)
 	if err != nil {
 		if !errors.IsUnsupportedError(err) {