Merge pull request #223 from zalando-incubator/document-watch-namespace

Make env var overwrite configmap setting for watching namespaces

cmd/main.go

@@ -27,14 +27,9 @@ func init() {
 	flag.BoolVar(&config.NoTeamsAPI, "noteamsapi", false, "Disable all access to the teams API")
 	flag.Parse()
 
-	config.Namespace = os.Getenv("WATCH_NAMESPACE")
-	if config.Namespace == "" {
-		config.Namespace = "default"
-	}
-
-	configMap := os.Getenv("CONFIG_MAP_NAME")
-	if configMap != "" {
-		err := config.ConfigMapName.Decode(configMap)
+	configMapRawName := os.Getenv("CONFIG_MAP_NAME")
+	if configMapRawName != "" {
+		err := config.ConfigMapName.Decode(configMapRawName)
 		if err != nil {
 			log.Fatalf("incorrect config map name")
 		}

manifests/configmap.yaml

@@ -3,6 +3,9 @@ kind: ConfigMap
 metadata:
   name: postgres-operator
 data:
+  # assumes the ns exists before the operator starts
+  # the env var with the same name may overwrite it in the operator pod
+  # watched_namespace: development
   service_account_name: operator
   cluster_labels: application:spilo
   cluster_name_label: version

manifests/postgres-operator.yaml

@@ -15,9 +15,10 @@ spec:
         image: registry.opensource.zalan.do/acid/postgres-operator:c17aabb
         imagePullPolicy: IfNotPresent
         env:
-        - name: WATCH_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
+        # uncomment to overwrite a similar setting from operator configmap
+        # - name: WATCHED_NAMESPACE
+        #  valueFrom:
+        #    fieldRef:
+        #      fieldPath: metadata.namespace
         - name: CONFIG_MAP_NAME
           value: "postgres-operator"

pkg/cluster/resources.go

@@ -110,7 +110,7 @@ func (c *Cluster) preScaleDown(newStatefulSet *v1beta1.StatefulSet) error {
 	}
 
 	podName := fmt.Sprintf("%s-0", c.Statefulset.Name)
-	masterCandidatePod, err := c.KubeClient.Pods(c.OpConfig.Namespace).Get(podName, metav1.GetOptions{})
+	masterCandidatePod, err := c.KubeClient.Pods(c.OpConfig.WatchedNamespace).Get(podName, metav1.GetOptions{})
 	if err != nil {
 		return fmt.Errorf("could not get master candidate pod: %v", err)
 	}

pkg/controller/controller.go

@@ -97,9 +97,18 @@ func (c *Controller) initOperatorConfig() {
 		c.logger.Infoln("no ConfigMap specified. Loading default values")
 	}
 
-	if configMapData["namespace"] == "" { // Namespace in ConfigMap has priority over env var
-		configMapData["namespace"] = c.config.Namespace
+	// env var takes priority over the same param from the operator ConfigMap
+	watchedNamespace := os.Getenv("WATCHED_NAMESPACE")
+	if watchedNamespace != "" {
+		c.logger.Infof("Watch the %q namespace specified in the env variable WATCHED_NAMESPACE\n", watchedNamespace)
+		configMapData["watched_namespace"] = watchedNamespace
 	}
+
+	if configMapData["watched_namespace"] == "" {
+		c.logger.Infoln("No namespace to watch specified. Fall back to watching the 'default' namespace.")
+		configMapData["watched_namespace"] = v1.NamespaceDefault
+	}
+
 	if c.config.NoDatabaseAccess {
 		configMapData["enable_database_access"] = "false"
 	}

pkg/controller/node.go

@@ -80,7 +80,7 @@ func (c *Controller) moveMasterPodsOffNode(node *v1.Node) {
 	opts := metav1.ListOptions{
 		LabelSelector: labels.Set(c.opConfig.ClusterLabels).String(),
 	}
-	podList, err := c.KubeClient.Pods(c.opConfig.Namespace).List(opts)
+	podList, err := c.KubeClient.Pods(c.opConfig.WatchedNamespace).List(opts)
 	if err != nil {
 		c.logger.Errorf("could not fetch list of the pods: %v", err)
 		return

pkg/controller/pod.go

@@ -17,7 +17,7 @@ func (c *Controller) podListFunc(options metav1.ListOptions) (runtime.Object, er
 		TimeoutSeconds:  options.TimeoutSeconds,
 	}
 
-	return c.KubeClient.Pods(c.opConfig.Namespace).List(opts)
+	return c.KubeClient.Pods(c.opConfig.WatchedNamespace).List(opts)
 }
 
 func (c *Controller) podWatchFunc(options metav1.ListOptions) (watch.Interface, error) {
@@ -27,7 +27,7 @@ func (c *Controller) podWatchFunc(options metav1.ListOptions) (watch.Interface,
 		TimeoutSeconds:  options.TimeoutSeconds,
 	}
 
-	return c.KubeClient.Pods(c.opConfig.Namespace).Watch(opts)
+	return c.KubeClient.Pods(c.opConfig.WatchedNamespace).Watch(opts)
 }
 
 func (c *Controller) dispatchPodEvent(clusterName spec.NamespacedName, event spec.PodEvent) {

pkg/controller/postgresql.go

@@ -46,7 +46,7 @@ func (c *Controller) clusterListFunc(options metav1.ListOptions) (runtime.Object
 
 	req := c.KubeClient.CRDREST.
 		Get().
-		Namespace(c.opConfig.Namespace).
+		Namespace(c.opConfig.WatchedNamespace).
 		Resource(constants.CRDResource).
 		VersionedParams(&options, metav1.ParameterCodec)
 
@@ -110,7 +110,7 @@ func (c *Controller) clusterWatchFunc(options metav1.ListOptions) (watch.Interfa
 	options.Watch = true
 	r, err := c.KubeClient.CRDREST.
 		Get().
-		Namespace(c.opConfig.Namespace).
+		Namespace(c.opConfig.WatchedNamespace).
 		Resource(constants.CRDResource).
 		VersionedParams(&options, metav1.ParameterCodec).
 		FieldsSelectorParam(nil).

pkg/controller/status.go

@@ -16,7 +16,7 @@ import (
 // ClusterStatus provides status of the cluster
 func (c *Controller) ClusterStatus(team, cluster string) (*spec.ClusterStatus, error) {
 	clusterName := spec.NamespacedName{
-		Namespace: c.opConfig.Namespace,
+		Namespace: c.opConfig.WatchedNamespace,
 		Name:      team + "-" + cluster,
 	}
 
@@ -92,7 +92,7 @@ func (c *Controller) GetStatus() *spec.ControllerStatus {
 // ClusterLogs dumps cluster ring logs
 func (c *Controller) ClusterLogs(team, name string) ([]*spec.LogEntry, error) {
 	clusterName := spec.NamespacedName{
-		Namespace: c.opConfig.Namespace,
+		Namespace: c.opConfig.WatchedNamespace,
 		Name:      team + "-" + name,
 	}
 
@@ -214,7 +214,7 @@ func (c *Controller) WorkerStatus(workerID uint32) (*spec.WorkerStatus, error) {
 // ClusterHistory dumps history of cluster changes
 func (c *Controller) ClusterHistory(team, name string) ([]*spec.Diff, error) {
 	clusterName := spec.NamespacedName{
-		Namespace: c.opConfig.Namespace,
+		Namespace: c.opConfig.WatchedNamespace,
 		Name:      team + "-" + name,
 	}
 

pkg/util/config/config.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"fmt"
+
 	"github.com/zalando-incubator/postgres-operator/pkg/spec"
 )
 
@@ -66,7 +67,7 @@ type Config struct {
 	Resources
 	Auth
 	Scalyr
-	Namespace                string            `name:"namespace"`
+	WatchedNamespace         string            `name:"watched_namespace"`
 	EtcdHost                 string            `name:"etcd_host" default:"etcd-client.default.svc.cluster.local:2379"`
 	DockerImage              string            `name:"docker_image" default:"registry.opensource.zalan.do/acid/spiloprivate-9.6:1.2-p4"`
 	ServiceAccountName       string            `name:"service_account_name" default:"operator"`