Merge pull request #195 from zalando-incubator/databases-rest-endpoint

Add a REST endpoint to list databases in all clusters

pkg/cluster/cluster.go

@@ -75,7 +75,8 @@ type Cluster struct {
 	oauthTokenGetter OAuthTokenGetter
 	KubeClient       k8sutil.KubernetesClient //TODO: move clients to the better place?
 	currentProcess   spec.Process
-	processMu        sync.RWMutex
+	processMu        sync.RWMutex // protects the current operation for reporting, no need to hold the master mutex
+	specMu           sync.RWMutex // protects the spec for reporting, no need to hold the master mutex
 }
 
 type compareStatefulsetResult struct {
@@ -437,7 +438,7 @@ func (c *Cluster) Update(oldSpec, newSpec *spec.Postgresql) error {
 	defer c.mu.Unlock()
 
 	c.setStatus(spec.ClusterStatusUpdating)
-	c.Postgresql = *newSpec
+	c.setSpec(newSpec)
 
 	defer func() {
 		if updateFailed {

pkg/cluster/sync.go

@@ -20,7 +20,7 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
-	c.Postgresql = *newSpec
+	c.setSpec(newSpec)
 
 	defer func() {
 		if err != nil {

pkg/cluster/util.go

@@ -1,9 +1,12 @@
 package cluster
 
 import (
+	"bytes"
+	"encoding/gob"
 	"encoding/json"
 	"fmt"
 	"math/rand"
+	"sort"
 	"strings"
 	"time"
 
@@ -18,7 +21,6 @@ import (
 	"github.com/zalando-incubator/postgres-operator/pkg/util/constants"
 	"github.com/zalando-incubator/postgres-operator/pkg/util/k8sutil"
 	"github.com/zalando-incubator/postgres-operator/pkg/util/retryutil"
-	"sort"
 )
 
 // OAuthTokenGetter provides the method for fetching OAuth tokens
@@ -386,3 +388,32 @@ func (c *Cluster) credentialSecretNameForCluster(username string, clusterName st
 func masterCandidate(replicas []spec.NamespacedName) spec.NamespacedName {
 	return replicas[rand.Intn(len(replicas))]
 }
+
+func cloneSpec(from *spec.Postgresql) (*spec.Postgresql, error) {
+	var (
+		buf    bytes.Buffer
+		result *spec.Postgresql
+		err    error
+	)
+	enc := gob.NewEncoder(&buf)
+	if err = enc.Encode(*from); err != nil {
+		return nil, fmt.Errorf("could not encode the spec: %v", err)
+	}
+	dec := gob.NewDecoder(&buf)
+	if err = dec.Decode(&result); err != nil {
+		return nil, fmt.Errorf("could not decode the spec: %v", err)
+	}
+	return result, nil
+}
+
+func (c *Cluster) setSpec(newSpec *spec.Postgresql) {
+	c.specMu.Lock()
+	c.Postgresql = *newSpec
+	c.specMu.Unlock()
+}
+
+func (c *Cluster) GetSpec() (*spec.Postgresql, error) {
+	c.specMu.RLock()
+	defer c.specMu.RUnlock()
+	return cloneSpec(&c.Postgresql)
+}