Provide more information about variable conflicts.

alexeyklyukin · alexeyklyukin · commit 0e255f82c6be · 2017-12-14T14:39:33.000+01:00
They are mentioned in the documentation and the operator will emit a
warning each time the variable from the pod environment configmap is
ignored because the same variable is defined by the operator.

Some minor changes in the variable names to make the code more readable.

Per review from Sergey Dudoladov.
diff --git a/README.md b/README.md
@@ -178,6 +178,8 @@ data:
 
 This ConfigMap is then added as a source of environment variables to the Postgres StatefulSet/pods.
 
+:exclamation: Note that there are environment variables defined by the operator itself in order to pass parameters to the Spilo image. The values from the operator for those variables will take precedence over those defined in the `pod_environment_configmap`.
+
 # Setup development environment
 
 The following steps guide you through the setup to work on the operator itself.
diff --git a/pkg/cluster/k8sres.go b/pkg/cluster/k8sres.go
@@ -282,7 +282,7 @@ func (c *Cluster) generatePodTemplate(resourceRequirements *v1.ResourceRequireme
 	patroniParameters *spec.Patroni,
 	cloneDescription *spec.CloneDescription,
 	dockerImage *string,
-	extraEnv map[string]string) *v1.PodTemplateSpec {
+	customPodEnvVars map[string]string) *v1.PodTemplateSpec {
 	spiloConfiguration := c.generateSpiloJSONConfiguration(pgParameters, patroniParameters)
 
 	envVars := []v1.EnvVar{
@@ -373,14 +373,17 @@ func (c *Cluster) generatePodTemplate(resourceRequirements *v1.ResourceRequireme
 	for _, envVar := range envVars {
 		envVarsMap[envVar.Name] = envVar.Value
 	}
-	for name := range extraEnv {
+	for name := range customPodEnvVars {
 		if _, ok := envVarsMap[name]; !ok {
 			names = append(names, name)
+		} else {
+			c.logger.Warningf("variable %q value from %q is ignored: conflict with the definition from the operator",
+				name, c.OpConfig.PodEnvironmentConfigMap)
 		}
 	}
 	sort.Strings(names)
 	for _, name := range names {
-		envVars = append(envVars, v1.EnvVar{Name: name, Value: extraEnv[name]})
+		envVars = append(envVars, v1.EnvVar{Name: name, Value: customPodEnvVars[name]})
 	}
 
 	privilegedMode := true
@@ -447,15 +450,15 @@ func (c *Cluster) generateStatefulSet(spec *spec.PostgresSpec) (*v1beta1.Statefu
 	if err != nil {
 		return nil, fmt.Errorf("could not generate resource requirements: %v", err)
 	}
-	var extraEnv map[string]string
+	var customPodEnvVars map[string]string
 	if c.OpConfig.PodEnvironmentConfigMap != "" {
 		if cm, err := c.KubeClient.ConfigMaps(c.Namespace).Get(c.OpConfig.PodEnvironmentConfigMap, metav1.GetOptions{}); err != nil {
 			return nil, fmt.Errorf("could not read PodEnvironmentConfigMap: %v", err)
 		} else {
-			extraEnv = cm.Data
+			customPodEnvVars = cm.Data
 		}
 	}
-	podTemplate := c.generatePodTemplate(resourceRequirements, &spec.Tolerations, &spec.PostgresqlParam, &spec.Patroni, &spec.Clone, &spec.DockerImage, extraEnv)
+	podTemplate := c.generatePodTemplate(resourceRequirements, &spec.Tolerations, &spec.PostgresqlParam, &spec.Patroni, &spec.Clone, &spec.DockerImage, customPodEnvVars)
 	volumeClaimTemplate, err := generatePersistentVolumeClaimTemplate(spec.Volume.Size, spec.Volume.StorageClass)
 	if err != nil {
 		return nil, fmt.Errorf("could not generate volume claim template: %v", err)
