continous healing based on crawler (#10103)

Design: https://gist.github.com/klauspost/792fe25c315caf1dd15c8e79df124914

cmd/admin-heal-ops.go

@@ -654,9 +654,11 @@ func (h *healSequence) queueHealTask(source healSource, healType madmin.HealItem
 		if !h.reportProgress {
 			// Object might have been deleted, by the time heal
 			// was attempted, we should ignore this object and
-			// return success.
+			// return the error and not calculate this object
+			// as part of the metrics.
 			if isErrObjectNotFound(res.err) || isErrVersionNotFound(res.err) {
-				return nil
+				// Return the error so that caller can handle it.
+				return res.err
 			}
 
 			h.mutex.Lock()
@@ -720,6 +722,8 @@ func (h *healSequence) healItemsFromSourceCh() error {
 			if err := h.queueHealTask(source, itemType); err != nil {
 				switch err.(type) {
 				case ObjectExistsAsDirectory:
+				case ObjectNotFound:
+				case VersionNotFound:
 				default:
 					logger.LogIf(h.ctx, fmt.Errorf("Heal attempt failed for %s: %w",
 						pathJoin(source.bucket, source.object), err))
@@ -793,17 +797,17 @@ func (h *healSequence) healMinioSysMeta(metaPrefix string) func() error {
 				return errHealStopSignalled
 			}
 
-			herr := h.queueHealTask(healSource{
+			err := h.queueHealTask(healSource{
 				bucket:    bucket,
 				object:    object,
 				versionID: versionID,
 			}, madmin.HealItemBucketMetadata)
 			// Object might have been deleted, by the time heal
 			// was attempted we ignore this object an move on.
-			if isErrObjectNotFound(herr) || isErrVersionNotFound(herr) {
+			if isErrObjectNotFound(err) || isErrVersionNotFound(err) {
 				return nil
 			}
-			return herr
+			return err
 		})
 	}
 }
@@ -904,9 +908,15 @@ func (h *healSequence) healObject(bucket, object, versionID string) error {
 		return errHealStopSignalled
 	}
 
-	return h.queueHealTask(healSource{
+	err := h.queueHealTask(healSource{
 		bucket:    bucket,
 		object:    object,
 		versionID: versionID,
 	}, madmin.HealItemObject)
+	// Object might have been deleted, by the time heal
+	// was attempted we ignore this object an move on.
+	if isErrObjectNotFound(err) || isErrVersionNotFound(err) {
+		return nil
+	}
+	return err
 }