Add last-deployed annotation to deployment status

internal/controller/function_controller.go

@@ -22,6 +22,7 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/functions-dev/func-operator/internal/funccli"
 	fn "github.com/functions-dev/func-operator/internal/function"
@@ -52,6 +53,9 @@ import (
 const (
 	deployFunctionRoleName = "func-operator-deploy-function"
 	controllerConfigName   = "func-operator-controller-config"
+
+	funcAnnotationPrefix       = "functions.knative.dev/"
+	funcAnnotationLastDeployed = funcAnnotationPrefix + "last-deployed"
 )
 
 // FunctionReconciler reconciles a Function object
@@ -161,6 +165,16 @@ func (r *FunctionReconciler) reconcile(ctx context.Context, function *v1alpha1.F
 
 	function.Status.Name = metadata.Name
 
+	if val, ok := function.Annotations[funcAnnotationLastDeployed]; ok {
+		t, err := time.Parse(time.RFC3339, val)
+		if err != nil {
+			// log a warning, but don't return error, as this can't resolve on its own
+			log.FromContext(ctx).Info("could not parse "+funcAnnotationLastDeployed+" annotation", "error", err)
+		} else {
+			function.Status.Deployment.ImageBuilt = metav1.NewTime(t)
+		}
+	}
+
 	if err := r.ensureDeployment(ctx, function, repo, metadata); err != nil {
 		return fmt.Errorf("deploying function failed: %w", err)
 	}
@@ -295,6 +309,7 @@ func (r *FunctionReconciler) handleMiddlewareUpdate(ctx context.Context, functio
 
 			function.Status.Middleware.PendingRebuild = false
 			function.Status.Middleware.LastRebuild = metav1.Now()
+			function.Status.Deployment.ImageBuilt = metav1.Now()
 
 			function.RecordHistoryEvent(fmt.Sprintf("Middleware updated from %q to %q", functionDescribe.Middleware.Version, latestMiddleware))
 

internal/controller/function_controller_test.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"time"
 
 	"github.com/functions-dev/func-operator/internal/funccli"
 	"github.com/functions-dev/func-operator/internal/git"
@@ -463,6 +464,29 @@ var _ = Describe("Function Controller", func() {
 					Expect(annotations).NotTo(HaveKey("functions.knative.dev/reason"))
 				},
 			}),
+
+			Entry("should add last-deployed annotation in deployment status details", reconcileTestCase{
+				spec: defaultSpec,
+				annotations: map[string]string{
+					funcAnnotationLastDeployed: "2026-01-02T15:04:05+06:00",
+				},
+				configureMocks: func(funcMock *funccli.MockManager, gitMock *git.MockManager) {
+					funcMock.EXPECT().Describe(mock.Anything, functionName, resourceNamespace).Return(functions.Instance{
+						Middleware: functions.Middleware{
+							Version: "v1.0.0",
+						},
+					}, nil)
+					funcMock.EXPECT().GetLatestMiddlewareVersion(mock.Anything, mock.Anything, mock.Anything).Return("v1.0.0", nil)
+					funcMock.EXPECT().GetMiddlewareVersion(mock.Anything, functionName, resourceNamespace).Return("v1.0.0", nil)
+
+					gitMock.EXPECT().CloneRepository(mock.Anything, "https://github.com/foo/bar", "", "my-branch", mock.Anything).Return(createTmpGitRepo(functions.Function{Name: "func-go"}), nil)
+				},
+				statusChecks: func(status *functionsdevv1alpha1.FunctionStatus) {
+					expectedTime, err := time.Parse(time.RFC3339, "2026-01-02T15:04:05+06:00")
+					Expect(err).NotTo(HaveOccurred())
+					Expect(status.Deployment.ImageBuilt.UTC()).To(Equal(expectedTime.UTC()))
+				},
+			}),
 			Entry("should set ServiceReady condition to false with unknown reason when ready status is empty", reconcileTestCase{
 				spec: defaultSpec,
 				configureMocks: func(funcMock *funccli.MockManager, gitMock *git.MockManager) {

internal/controller/function_predicate.go

@@ -24,8 +24,6 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 )
 
-const funcAnnotationPrefix = "functions.knative.dev/"
-
 // FuncAnnotationChangedPredicate triggers reconciliation when annotations
 // with the "functions.knative.dev/" prefix are added or changed.
 type FuncAnnotationChangedPredicate struct {