Propagate annotations to the StatefulSet (#932)

* Initial commit

* Corrections

- set the type of the new  configuration parameter to be array of
  strings
- propagate the annotations to statefulset at sync

* Enable regular expression matching

* Improvements

-handle rollingUpdate flag
-modularize code
-rename config parameter name

* fix merge error

* Pass annotations to connection pooler deployment

* update code-gen

* Add documentation and update manifests

* add e2e test and introduce option in configmap

* fix service annotations test

* Add unit test

* fix e2e tests

* better key lookup of annotations tests

* add debug message for annotation tests

* Fix typos

* minor fix for looping

* Handle update path and renaming

- handle the update path to update sts and connection pooler deployment.
  This way no need to wait for sync
- rename the parameter to downscaler_annotations
- handle other review comments

* another try to fix python loops

* Avoid unneccessary update events

* Update manifests

* some final polishing

* fix cluster_test after polishing

Co-authored-by: Rafia Sabih <rafia.sabih@zalando.de>
Co-authored-by: Felix Kunde <felix-kunde@gmx.de>

pkg/cluster/resources.go

@@ -853,3 +853,24 @@ func (c *Cluster) updateConnectionPoolerDeployment(oldDeploymentSpec, newDeploym
 
 	return deployment, nil
 }
+
+//updateConnectionPoolerAnnotations updates the annotations of connection pooler deployment
+func (c *Cluster) updateConnectionPoolerAnnotations(annotations map[string]string) (*appsv1.Deployment, error) {
+	c.logger.Debugf("updating connection pooler annotations")
+	patchData, err := metaAnnotationsPatch(annotations)
+	if err != nil {
+		return nil, fmt.Errorf("could not form patch for the deployment metadata: %v", err)
+	}
+	result, err := c.KubeClient.Deployments(c.ConnectionPooler.Deployment.Namespace).Patch(
+		context.TODO(),
+		c.ConnectionPooler.Deployment.Name,
+		types.MergePatchType,
+		[]byte(patchData),
+		metav1.PatchOptions{},
+		"")
+	if err != nil {
+		return nil, fmt.Errorf("could not patch connection pooler annotations %q: %v", patchData, err)
+	}
+	return result, nil
+
+}