feat: fix force-update for zero-replica deployments by reading image tags from spec

Signed-off-by: chansuke <[email protected]>

Author: chansuke

pkg/argocd/argocd.go

@@ -592,7 +592,14 @@ func GetImagesFromApplication(app *v1alpha1.Application) image.ContainerImageLis
 	annotations := app.Annotations
 	for _, img := range *parseImageList(annotations) {
 		if img.HasForceUpdateOptionAnnotation(annotations, common.ImageUpdaterAnnotationPrefix) {
-			img.ImageTag = nil // the tag from the image list will be a version constraint, which isn't a valid tag
+			// for force-update images, try to get the current image tag from the spec
+			// this helps handle cases where there are 0 replicas
+			currentImage := getImageFromSpec(app, img)
+			if currentImage != nil {
+				img.ImageTag = currentImage.ImageTag
+			} else {
+				img.ImageTag = nil
+			}
 			images = append(images, img)
 		}
 	}
@@ -727,3 +734,51 @@ func (a ApplicationType) String() string {
 		return "Unknown"
 	}
 }
+
+// getImageFromSpec tries to find the current image tag from the application spec
+func getImageFromSpec(app *v1alpha1.Application, targetImage *image.ContainerImage) *image.ContainerImage {
+	appType := getApplicationType(app)
+	source := getApplicationSource(app)
+
+	if source == nil {
+		return nil
+	}
+
+	switch appType {
+	case ApplicationTypeHelm:
+		if source.Helm != nil && source.Helm.Parameters != nil {
+			for _, param := range source.Helm.Parameters {
+				if param.Name == "image.tag" || param.Name == "image.version" {
+					foundImage := image.NewFromIdentifier(fmt.Sprintf("%s:%s", targetImage.ImageName, param.Value))
+					if foundImage != nil && foundImage.ImageName == targetImage.ImageName {
+						return foundImage
+					}
+				}
+				if param.Name == "image" || param.Name == "image.repository" {
+					foundImage := image.NewFromIdentifier(param.Value)
+					if foundImage != nil && foundImage.ImageName == targetImage.ImageName {
+						return foundImage
+					}
+				}
+			}
+		}
+	case ApplicationTypeKustomize:
+		if source.Kustomize != nil && source.Kustomize.Images != nil {
+			for _, kustomizeImage := range source.Kustomize.Images {
+				imageStr := string(kustomizeImage)
+				if strings.Contains(imageStr, "=") {
+					parts := strings.SplitN(imageStr, "=", 2)
+					if len(parts) == 2 {
+						imageStr = parts[1]
+					}
+				}
+				foundImage := image.NewFromIdentifier(imageStr)
+				if foundImage != nil && foundImage.ImageName == targetImage.ImageName {
+					return foundImage
+				}
+			}
+		}
+	}
+
+	return nil
+}

pkg/argocd/argocd_test.go

@@ -81,6 +81,75 @@ func Test_GetImagesFromApplication(t *testing.T) {
 		assert.Equal(t, "nginx", imageList[0].ImageName)
 		assert.Nil(t, imageList[0].ImageTag)
 	})
+
+	t.Run("Get list of images from application with force-update and zero replicas - Helm", func(t *testing.T) {
+		application := &v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name:      "test-app",
+				Namespace: "argocd",
+				Annotations: map[string]string{
+					fmt.Sprintf(registryCommon.Prefixed(common.ImageUpdaterAnnotationPrefix, registryCommon.ForceUpdateOptionAnnotationSuffix), "myapp"): "true",
+					common.ImageUpdaterAnnotation: "myapp=myregistry/myapp",
+				},
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Source: &v1alpha1.ApplicationSource{
+					Helm: &v1alpha1.ApplicationSourceHelm{
+						Parameters: []v1alpha1.HelmParameter{
+							{
+								Name:  "image.tag",
+								Value: "1.2.3",
+							},
+						},
+					},
+				},
+			},
+			Status: v1alpha1.ApplicationStatus{
+				SourceType: v1alpha1.ApplicationSourceTypeHelm,
+				Summary: v1alpha1.ApplicationSummary{
+					Images: []string{}, // Empty - simulating 0 replicas
+				},
+			},
+		}
+		imageList := GetImagesFromApplication(application)
+		require.Len(t, imageList, 1)
+		assert.Equal(t, "myregistry/myapp", imageList[0].ImageName)
+		assert.NotNil(t, imageList[0].ImageTag)
+		assert.Equal(t, "1.2.3", imageList[0].ImageTag.TagName)
+	})
+
+	t.Run("Get list of images from application with force-update and zero replicas - Kustomize", func(t *testing.T) {
+		application := &v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name:      "test-app",
+				Namespace: "argocd",
+				Annotations: map[string]string{
+					fmt.Sprintf(registryCommon.Prefixed(common.ImageUpdaterAnnotationPrefix, registryCommon.ForceUpdateOptionAnnotationSuffix), "myapp"): "true",
+					common.ImageUpdaterAnnotation: "myapp=myregistry/myapp",
+				},
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Source: &v1alpha1.ApplicationSource{
+					Kustomize: &v1alpha1.ApplicationSourceKustomize{
+						Images: v1alpha1.KustomizeImages{
+							"myregistry/myapp:2.3.4",
+						},
+					},
+				},
+			},
+			Status: v1alpha1.ApplicationStatus{
+				SourceType: v1alpha1.ApplicationSourceTypeKustomize,
+				Summary: v1alpha1.ApplicationSummary{
+					Images: []string{}, // Empty - simulating 0 replicas
+				},
+			},
+		}
+		imageList := GetImagesFromApplication(application)
+		require.Len(t, imageList, 1)
+		assert.Equal(t, "myregistry/myapp", imageList[0].ImageName)
+		assert.NotNil(t, imageList[0].ImageTag)
+		assert.Equal(t, "2.3.4", imageList[0].ImageTag.TagName)
+	})
 }
 
 func Test_GetImagesAndAliasesFromApplication(t *testing.T) {

pkg/argocd/update.go

@@ -167,9 +167,23 @@ func UpdateApplication(updateConf *UpdateConfiguration, state *SyncIterationStat
 	for _, applicationImage := range updateConf.UpdateApp.Images {
 		updateableImage := applicationImages.ContainsImage(applicationImage, false)
 		if updateableImage == nil {
-			log.WithContext().AddField("application", app).Debugf("Image '%s' seems not to be live in this application, skipping", applicationImage.ImageName)
-			result.NumSkipped += 1
-			continue
+			// for force-update images, we should not skip them even if they're not "live"
+			// this handles cases like 0-replica deployments or CronJobs without active jobs
+			if applicationImage.HasForceUpdateOptionAnnotation(updateConf.UpdateApp.Application.Annotations, common.ImageUpdaterAnnotationPrefix) {
+				// find the image in our list that matches by name
+				for _, img := range applicationImages {
+					if img.ImageName == applicationImage.ImageName {
+						updateableImage = img
+						break
+					}
+				}
+			}
+
+			if updateableImage == nil {
+				log.WithContext().AddField("application", app).Debugf("Image '%s' seems not to be live in this application, skipping", applicationImage.ImageName)
+				result.NumSkipped += 1
+				continue
+			}
 		}
 
 		// In some cases, the running image has no tag set. We create a dummy