From ac96e788b77fcec3eff8f8c016fee4506b9656bc Mon Sep 17 00:00:00 2001
From: Christoph Barbian <christoph.barbian@sap.com>
Date: Fri, 20 Dec 2024 14:56:02 +0100
Subject: [PATCH] refactor force-reconcile

---
 .gitignore                   |  2 +-
 pkg/reconciler/reconciler.go | 10 ++++++++--
 pkg/reconciler/util.go       | 24 ++----------------------
 3 files changed, 11 insertions(+), 25 deletions(-)

diff --git a/.gitignore b/.gitignore
index 19e7e8d..f276c03 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,7 +6,7 @@
 *.dylib
 bin
 testbin/*
-__debug_bin
+*__debug_bin*
 
 # Test binary, build with `go test -c`
 *.test
diff --git a/pkg/reconciler/reconciler.go b/pkg/reconciler/reconciler.go
index e416760..ac21871 100644
--- a/pkg/reconciler/reconciler.go
+++ b/pkg/reconciler/reconciler.go
@@ -11,6 +11,7 @@ import (
 	"fmt"
 	"math"
 	"strconv"
+	"time"
 
 	"github.com/iancoleman/strcase"
 	"github.com/pkg/errors"
@@ -387,7 +388,7 @@ func (r *Reconciler) Apply(ctx context.Context, inventory *[]*InventoryItem, obj
 		// calculate object digest
 		// note: if the effective reconcile policy of an object changes, it will always be reconciled at least one more time;
 		// this is in particular the case if the policy changes from or to ReconcilePolicyOnce.
-		digest, err := calculateObjectDigest(object, item, componentRevision, getReconcilePolicy(object))
+		digest, err := calculateObjectDigest(object, componentRevision, getReconcilePolicy(object))
 		if err != nil {
 			return false, errors.Wrapf(err, "error calculating digest for object %s", types.ObjectKeyToString(object))
 		}
@@ -632,14 +633,18 @@ func (r *Reconciler) Apply(ctx context.Context, inventory *[]*InventoryItem, obj
 				setAnnotation(object, r.annotationKeyDigest, item.Digest)
 
 				updatePolicy := getUpdatePolicy(object)
+				now := time.Now()
 				if existingObject == nil {
 					if err := r.createObject(ctx, object, nil, updatePolicy); err != nil {
 						return false, errors.Wrapf(err, "error creating object %s", item)
 					}
 					item.Phase = PhaseCreating
 					item.Status = status.InProgressStatus
+					item.LastAppliedAt = &metav1.Time{Time: now}
 					numUnready++
-				} else if existingObject.GetDeletionTimestamp().IsZero() && existingObject.GetAnnotations()[r.annotationKeyDigest] != item.Digest {
+				} else if existingObject.GetDeletionTimestamp().IsZero() &&
+					// TODO: make force-reconcile period (60 minutes as of now) configurable
+					(existingObject.GetAnnotations()[r.annotationKeyDigest] != item.Digest || item.LastAppliedAt != nil && item.LastAppliedAt.Time.Before(now.Add(-60*time.Minute))) {
 					switch updatePolicy {
 					case UpdatePolicyRecreate:
 						// TODO: perform an additional owner id check
@@ -654,6 +659,7 @@ func (r *Reconciler) Apply(ctx context.Context, inventory *[]*InventoryItem, obj
 					}
 					item.Phase = PhaseUpdating
 					item.Status = status.InProgressStatus
+					item.LastAppliedAt = &metav1.Time{Time: now}
 					numUnready++
 				} else {
 					existingStatus, err := r.statusAnalyzer.ComputeStatus(existingObject)
diff --git a/pkg/reconciler/util.go b/pkg/reconciler/util.go
index e35ac58..72e204b 100644
--- a/pkg/reconciler/util.go
+++ b/pkg/reconciler/util.go
@@ -11,10 +11,7 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
-	"regexp"
-	"strconv"
 	"strings"
-	"time"
 
 	"github.com/pkg/errors"
 	"github.com/sap/go-generics/slices"
@@ -61,7 +58,7 @@ func checkRange(x int, min int, max int) error {
 	return nil
 }
 
-func calculateObjectDigest(obj client.Object, item *InventoryItem, revision int64, reconcilePolicy ReconcilePolicy) (string, error) {
+func calculateObjectDigest(obj client.Object, revision int64, reconcilePolicy ReconcilePolicy) (string, error) {
 	if reconcilePolicy == ReconcilePolicyOnce {
 		return "__once__", nil
 	}
@@ -85,24 +82,7 @@ func calculateObjectDigest(obj client.Object, item *InventoryItem, revision int6
 		digest = fmt.Sprintf("%s@%d", digest, revision)
 	}
 
-	previousDigest := ""
-	previousTimestamp := int64(0)
-	if item != nil {
-		if m := regexp.MustCompile(`^([0-9a-f@]+):(\d{10})$`).FindStringSubmatch(item.Digest); m != nil {
-			previousDigest = m[1]
-			previousTimestamp = must(strconv.ParseInt(m[2], 10, 64))
-		}
-	}
-	now := time.Now().Unix()
-	timestamp := int64(0)
-	// TODO: make force-reconcile period configurable (globally, per object, ...?)
-	if previousDigest == digest && now-previousTimestamp <= 3600 {
-		timestamp = previousTimestamp
-	} else {
-		timestamp = now
-	}
-
-	return fmt.Sprintf("%s:%d", digest, timestamp), nil
+	return digest, nil
 }
 
 func setLabel(obj client.Object, key string, value string) {