feat(controller): make Go (ADK) runtime agent image independently configurable

go/core/internal/controller/translator/agent/adk_api_translator.go

@@ -128,6 +128,16 @@ var PythonADKFullImageDigest string
 var GoADKImageDigest string
 var GoADKFullImageDigest string
 
+// DefaultGoImageConfig is the image config for the Go (ADK) runtime agent.
+// Regular agents reference it by tag; sandbox agents pin by digest via
+// GoADKImageDigest / GoADKFullImageDigest.
+var DefaultGoImageConfig = ImageConfig{
+	Registry:   "ghcr.io",
+	Tag:        version.Get().Version,
+	PullPolicy: string(corev1.PullIfNotPresent),
+	Repository: "kagent-dev/kagent/golang-adk",
+}
+
 // DefaultSkillsInitImageConfig is the image config for the skills-init container
 // that clones skill repositories from Git and pulls OCI skill images.
 var DefaultSkillsInitImageConfig = ImageConfig{

go/core/internal/controller/translator/agent/deployments.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"maps"
 	"slices"
-	"strings"
 
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
@@ -92,31 +91,14 @@ func getDefaultNodeSelector(incoming map[string]string) map[string]string {
 	return nodeSelector
 }
 
-// getRuntimeImageRepository returns the image repository for a given runtime.
-// It respects DefaultImageConfig.Repository for the Python runtime, and derives
-// the Go runtime repository by replacing the last path segment with "golang-adk".
-// This ensures custom repository configurations (e.g., --image-repository flag) work correctly.
+// getRuntimeImageRepository returns the image repository for a given runtime:
+// DefaultGoImageConfig.Repository for the Go runtime, DefaultImageConfig.Repository
+// otherwise.
 func getRuntimeImageRepository(runtime v1alpha2.DeclarativeRuntime) string {
-	switch runtime {
-	case v1alpha2.DeclarativeRuntime_Go:
-		// Derive Go runtime repository from the default Python repository
-		// by replacing the last segment (typically "app") with "golang-adk".
-		// This respects any custom repository configuration.
-		pythonRepo := DefaultImageConfig.Repository
-		lastSlash := strings.LastIndex(pythonRepo, "/")
-		if lastSlash == -1 {
-			// No slash found, repository is just the image name
-			return "golang-adk"
-		}
-		baseRepo := pythonRepo[:lastSlash]
-		return baseRepo + "/golang-adk"
-	case v1alpha2.DeclarativeRuntime_Python:
-		// Use the configured Python repository as-is
-		return DefaultImageConfig.Repository
-	default:
-		// Default to Python (should never happen due to enum validation)
-		return DefaultImageConfig.Repository
+	if runtime == v1alpha2.DeclarativeRuntime_Go {
+		return DefaultGoImageConfig.Repository
 	}
+	return DefaultImageConfig.Repository
 }
 
 // validateExtraContainers checks that none of the extra containers use the
@@ -143,7 +125,7 @@ func resolvePythonRuntimeImage(registry string, full, pinDigest bool) (string, e
 		digest = PythonADKFullImageDigest
 		imageLabel = "app-full"
 	}
-	return resolveRuntimeImage(registry, repo, digest, imageLabel, full, pinDigest)
+	return resolveRuntimeImage(registry, repo, DefaultImageConfig.Tag, digest, imageLabel, full, pinDigest)
 }
 
 func resolveGoRuntimeImage(registry string, full, pinDigest bool) (string, error) {
@@ -154,7 +136,7 @@ func resolveGoRuntimeImage(registry string, full, pinDigest bool) (string, error
 		digest = GoADKFullImageDigest
 		imageLabel = "golang-adk-full"
 	}
-	return resolveRuntimeImage(registry, repo, digest, imageLabel, full, pinDigest)
+	return resolveRuntimeImage(registry, repo, DefaultGoImageConfig.Tag, digest, imageLabel, full, pinDigest)
 }
 
 // resolveRuntimeImage builds the image reference for a declarative agent runtime.
@@ -168,9 +150,8 @@ func resolveGoRuntimeImage(registry string, full, pinDigest bool) (string, error
 // Sandbox agents require pinDigest: Substrate ActorTemplate validation rejects
 // image refs without a digest, so those use the link-time (or flag-overridden)
 // runtime image digests.
-func resolveRuntimeImage(registry, repository, digest, imageLabel string, full, pinDigest bool) (string, error) {
+func resolveRuntimeImage(registry, repository, tag, digest, imageLabel string, full, pinDigest bool) (string, error) {
 	if !pinDigest {
-		tag := DefaultImageConfig.Tag
 		if full {
 			tag += "-full"
 		}
@@ -210,8 +191,16 @@ func resolveInlineDeployment(agent v1alpha2.AgentObject, mdd *modelDeploymentDat
 	// Determine runtime (defaults to python when spec.declarative.runtime is unset).
 	runtime := v1alpha2.EffectiveDeclarativeRuntime(agent.GetAgentSpec())
 
-	// Get registry
-	registry := DefaultImageConfig.Registry
+	// Resolve base registry and pull policy; the Go runtime uses DefaultGoImageConfig.
+	baseRegistry := DefaultImageConfig.Registry
+	basePullPolicy := DefaultImageConfig.PullPolicy
+	if runtime == v1alpha2.DeclarativeRuntime_Go {
+		baseRegistry = DefaultGoImageConfig.Registry
+		basePullPolicy = DefaultGoImageConfig.PullPolicy
+	}
+
+	// Per-agent spec overrides take precedence over all defaults.
+	registry := baseRegistry
 	if spec.ImageRegistry != "" {
 		registry = spec.ImageRegistry
 	}
@@ -236,7 +225,7 @@ func resolveInlineDeployment(agent v1alpha2.AgentObject, mdd *modelDeploymentDat
 		}
 	}
 
-	imagePullPolicy := corev1.PullPolicy(DefaultImageConfig.PullPolicy)
+	imagePullPolicy := corev1.PullPolicy(basePullPolicy)
 	if spec.ImagePullPolicy != "" {
 		imagePullPolicy = corev1.PullPolicy(spec.ImagePullPolicy)
 	}

go/core/internal/controller/translator/agent/imageconfig_test.go

@@ -131,8 +131,13 @@ func TestResolvePythonRuntimeImageWithoutDigest(t *testing.T) {
 
 func TestResolveRuntimeImageByTag(t *testing.T) {
 	originalTag := DefaultImageConfig.Tag
-	t.Cleanup(func() { DefaultImageConfig.Tag = originalTag })
+	originalGoTag := DefaultGoImageConfig.Tag
+	t.Cleanup(func() {
+		DefaultImageConfig.Tag = originalTag
+		DefaultGoImageConfig.Tag = originalGoTag
+	})
 	DefaultImageConfig.Tag = "v9.9.9"
+	DefaultGoImageConfig.Tag = "v8.8.8"
 
 	got, err := resolvePythonRuntimeImage("my-registry.example.com", false, false)
 	require.NoError(t, err)
@@ -144,11 +149,11 @@ func TestResolveRuntimeImageByTag(t *testing.T) {
 
 	got, err = resolveGoRuntimeImage("my-registry.example.com", false, false)
 	require.NoError(t, err)
-	require.Equal(t, "my-registry.example.com/kagent-dev/kagent/golang-adk:v9.9.9", got)
+	require.Equal(t, "my-registry.example.com/kagent-dev/kagent/golang-adk:v8.8.8", got)
 
 	got, err = resolveGoRuntimeImage("my-registry.example.com", true, false)
 	require.NoError(t, err)
-	require.Equal(t, "my-registry.example.com/kagent-dev/kagent/golang-adk:v9.9.9-full", got)
+	require.Equal(t, "my-registry.example.com/kagent-dev/kagent/golang-adk:v8.8.8-full", got)
 }
 
 func TestResolveRuntimeImageByTagIgnoresMissingDigest(t *testing.T) {