From 904d4e3c1511dbb5fdf486a855fb5bdf50e72878 Mon Sep 17 00:00:00 2001
From: irbekrm <irbekrm@gmail.com>
Date: Tue, 17 Aug 2021 08:31:49 +0100
Subject: [PATCH] Don't error if owner not found in cache

Signed-off-by: irbekrm <irbekrm@gmail.com>
---
 pkg/controller/BUILD.bazel |  1 +
 pkg/controller/util.go     | 18 +++++++++++++-----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/pkg/controller/BUILD.bazel b/pkg/controller/BUILD.bazel
index c0846e7b8..b3b986d79 100644
--- a/pkg/controller/BUILD.bazel
+++ b/pkg/controller/BUILD.bazel
@@ -20,6 +20,7 @@ go_library(
         "//pkg/logs:go_default_library",
         "//pkg/metrics:go_default_library",
         "@com_github_go_logr_logr//:go_default_library",
+        "@io_k8s_apimachinery//pkg/api/errors:go_default_library",
         "@io_k8s_apimachinery//pkg/api/resource:go_default_library",
         "@io_k8s_apimachinery//pkg/apis/meta/v1:go_default_library",
         "@io_k8s_apimachinery//pkg/runtime/schema:go_default_library",
diff --git a/pkg/controller/util.go b/pkg/controller/util.go
index 222403683..22aa1a977 100644
--- a/pkg/controller/util.go
+++ b/pkg/controller/util.go
@@ -22,6 +22,7 @@ import (
 	"time"
 
 	"github.com/go-logr/logr"
+	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/util/runtime"
@@ -74,13 +75,20 @@ func HandleOwnedResourceNamespacedFunc(log logr.Logger, queue workqueue.RateLimi
 			}
 
 			if refGV.Group == ownerGVK.Group && ref.Kind == ownerGVK.Kind {
-				// TODO: how to handle namespace of owner references?
-				order, err := get(metaobj.GetNamespace(), ref.Name)
-				if err != nil {
-					log.Error(err, "error getting referenced owning resource")
+				obj, err := get(metaobj.GetNamespace(), ref.Name)
+				// This function is always called with a getter
+				// that gets from informers cache. Because this
+				// is also called on cache sync it may be that
+				// the owner is not yet in the cache.
+				if err != nil && errors.IsNotFound(err) {
+					log.Info("owning resource not found in cache")
 					continue
 				}
-				objKey, err := KeyFunc(order)
+				if err != nil {
+					log.Error(err, "error getting referenced owning resource from cache")
+					continue
+				}
+				objKey, err := KeyFunc(obj)
 				if err != nil {
 					log.Error(err, "error computing key for resource")
 					continue