React to a change in the reconcileAt annotation

Despite the name, the contract of the reconcileAt mechanism is that
_changing it_ should trigger reconciliation outside the otherwise
specified schedule. To detect changes, this commit adds a field to the
status, and updates it when a scan has run.

api/v1alpha1/imagerepository_types.go

@@ -62,6 +62,12 @@ type ImageRepositoryStatus struct {
 	// LastScanResult contains the number of fetched tags.
 	// +optional
 	LastScanResult ScanResult `json:"lastScanResult,omitempty"`
+
+	// LastHandledReconcileAt records the value of the annotation used
+	// to prompt a scan, so that a change in value can be
+	// detected. The name is in common with other GitOps Toolkit
+	// controllers.
+	LastHandledReconcileAt string `json:"lastHandledReconcileAt,omitempty"`
 }
 
 // SetImageRepositoryReadiness sets the ready condition with the given status, reason and message.

config/crd/bases/image.toolkit.fluxcd.io_imagerepositories.yaml

@@ -95,6 +95,11 @@ spec:
                   - type
                   type: object
                 type: array
+              lastHandledReconcileAt:
+                description: LastHandledReconcileAt records the value of the annotation
+                  used to prompt a scan, so that a change in value can be detected.
+                  The name is in common with other GitOps Toolkit controllers.
+                type: string
               lastScanResult:
                 description: LastScanResult contains the number of fetched tags.
                 properties:

controllers/imagerepository_controller.go

@@ -154,6 +154,14 @@ func (r *ImageRepositoryReconciler) scan(ctx context.Context, imageRepo imagev1a
 	r.Database.SetTags(canonicalName, tags)
 
 	imageRepo.Status.LastScanResult.TagCount = len(tags)
+
+	// if the reconcile request annotation was set, consider it
+	// handled (NB it doesn't matter here if it was changed since last
+	// time)
+	if token, ok := imageRepo.GetAnnotations()[meta.ReconcileAtAnnotation]; ok {
+		imageRepo.Status.LastHandledReconcileAt = token
+	}
+
 	return imagev1alpha1.SetImageRepositoryReadiness(
 		imageRepo,
 		corev1.ConditionTrue,
@@ -177,12 +185,12 @@ func (r *ImageRepositoryReconciler) shouldScan(repo imagev1alpha1.ImageRepositor
 		return true, scanInterval
 	}
 
-	// allow for the "reconcile at" annotation
+	// Is the controller seeing this because the reconcileAt
+	// annotation was tweaked? Despite the name of the annotation, all
+	// that matters is that it's different.
 	if syncAt, ok := repo.GetAnnotations()[meta.ReconcileAtAnnotation]; ok {
-		if t, err := time.Parse(time.RFC3339Nano, syncAt); err == nil && t.Before(now) {
+		if syncAt != repo.Status.LastHandledReconcileAt {
 			return true, scanInterval
-		} else if err == nil {
-			return false, t.Sub(now)
 		}
 	}
 

controllers/scan_test.go

@@ -182,14 +182,17 @@ var _ = Describe("ImageRepository controller", func() {
 			lastScan := imagev1alpha1.GetLastTransitionTime(repoAfter)
 			Expect(lastScan).ToNot(BeNil())
 
+			requestToken := "this can be anything, so long as it's a change"
+
 			repoAfter.Annotations = map[string]string{
-				meta.ReconcileAtAnnotation: time.Now().Add(-time.Minute).Format(time.RFC3339Nano),
+				meta.ReconcileAtAnnotation: requestToken,
 			}
 			Expect(r.Update(ctx, &repoAfter)).To(Succeed())
 			Eventually(func() bool {
 				err := r.Get(context.Background(), objectName, &repoAfter)
 				return err == nil && imagev1alpha1.GetLastTransitionTime(repoAfter).After(lastScan.Time)
 			}, timeout, interval).Should(BeTrue())
+			Expect(repoAfter.Status.LastHandledReconcileAt).To(Equal(requestToken))
 		})
 	})
 })

go.sum

@@ -200,7 +200,6 @@ github.com/evanphx/json-patch v4.9.0+incompatible h1:kLcOMZeuLAJvL2BPWLMIj5oaZQo
 github.com/evanphx/json-patch v4.9.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fatih/color v1.9.0/go.mod h1:eQcE1qtQxscV5RaZvpXrrb8Drkc3/DdQ+uUYCNjL+zU=
-github.com/fluxcd/pkg v0.0.4 h1:fMA6GG3FTSBFDrlB026gQJhxj4xVuvcvwP3rhX/Yqrw=
 github.com/fluxcd/pkg/apis/meta v0.0.2 h1:kyA4Y0IzNjf1joBOnFqpWG7aNDHvtLExZcaHQM7qhRI=
 github.com/fluxcd/pkg/apis/meta v0.0.2/go.mod h1:nCNps5JJOcEQr3MNDmZqI4o0chjePSUYL6Q2ktDtotU=
 github.com/fluxcd/pkg/recorder v0.0.5 h1:D8qfupahIvh6ncCMn2yTHsrzG91S05sp4zdpsbKWeaU=