Auto update referenced resource

README.md

@@ -21,8 +21,27 @@ Reloader can watch changes in `ConfigMap` and `Secret` and do rolling upgrades o
 
 ## How to use Reloader
 
+For a `Deployment` called `foo` have a `ConfigMap` called `foo-configmap` or `Secret` called `foo-secret` or both. Then add this annotation to main metadata of your `Deployment`
+
+```yaml
+kind: Deployment
+metadata:
+  annotations:
+    reloader.stakater.com/auto: "true"
+spec:
+  template:
+    metadata:
+```
+
+This will discover deployments/daemonsets/statefulset automatically where `foo-configmap` or `foo-secret` is being used either via environment variable or from volume mount. And it will perform rolling upgrade on related pods when `foo-configmap` or `foo-secret`are updated.
+
+We can also specify a specific configmap or secret which would trigger rolling upgrade only upon change in our specified configmap or secret, this way, it will not trigger rolling upgrade upon changes in all configmaps or secrets used in a deployment, daemonset or statefulset.
+To do this either set `reloader.stakater.com/auto: "false"` or remove this annotation altogather, and use annotations mentioned [here](#Configmap) or [here](#Secret)
+
 ### Configmap
 
+To perform rolling upgrade when change happens only on specific configmaps use below annotation.
+
 For a `Deployment` called `foo` have a `ConfigMap` called `foo-configmap`. Then add this annotation to main metadata of your `Deployment`
 
 ```yaml
@@ -49,6 +68,8 @@ spec:
 
 ### Secret
 
+To perform rolling upgrade when change happens only on specific secrets use below annotation.
+
 For a `Deployment` called `foo` have a `Secret` called `foo-secret`. Then add this annotation to main metadata of  your `Deployment`
 
 ```yaml
@@ -73,6 +94,9 @@ spec:
     metadata:
 ```
 
+### NOTE
+`reloader.stakater.com/auto: "true"` will always override when use with either `secret.reloader.stakater.com/reload` or `configmap.reloader.stakater.com/reload` annotation.
+
 ## Deploying to Kubernetes
 
 You can deploy Reloader by following methods:

deployments/kubernetes/chart/reloader/templates/clusterrole.yaml

@@ -1,4 +1,3 @@
----
 {{- if and .Values.reloader.watchGlobally (.Values.reloader.rbac.enabled) }}
 apiVersion: rbac.authorization.k8s.io/v1beta1
 kind: ClusterRole

deployments/kubernetes/chart/reloader/templates/clusterrolebinding.yaml

@@ -1,5 +1,4 @@
 {{- if and .Values.reloader.watchGlobally (.Values.reloader.rbac.enabled) }}
----
 apiVersion: rbac.authorization.k8s.io/v1beta1
 kind: ClusterRoleBinding
 metadata:

deployments/kubernetes/chart/reloader/templates/rolebinding.yaml

@@ -1,5 +1,4 @@
 {{- if and (not (.Values.reloader.watchGlobally)) (.Values.reloader.rbac.enabled) }}
----
 apiVersion: rbac.authorization.k8s.io/v1beta1
 kind: RoleBinding
 metadata:

internal/pkg/callbacks/rolling_upgrade.go

@@ -16,6 +16,9 @@ type ItemsFunc func(kubernetes.Interface, string) []interface{}
 //ContainersFunc is a generic func to return containers
 type ContainersFunc func(interface{}) []v1.Container
 
+//VolumesFunc is a generic func to return volumes
+type VolumesFunc func(interface{}) []v1.Volume
+
 //UpdateFunc performs the resource update
 type UpdateFunc func(kubernetes.Interface, string, interface{}) error
 
@@ -24,6 +27,7 @@ type RollingUpgradeFuncs struct {
 	ItemsFunc      ItemsFunc
 	ContainersFunc ContainersFunc
 	UpdateFunc     UpdateFunc
+	VolumesFunc    VolumesFunc
 	ResourceType   string
 }
 
@@ -89,3 +93,18 @@ func UpdateStatefulset(client kubernetes.Interface, namespace string, resource i
 	_, err := client.AppsV1beta1().StatefulSets(namespace).Update(&statefulSet)
 	return err
 }
+
+// GetDeploymentVolumes returns the Volumes of given deployment
+func GetDeploymentVolumes(item interface{}) []v1.Volume {
+	return item.(v1beta1.Deployment).Spec.Template.Spec.Volumes
+}
+
+// GetDaemonSetVolumes returns the Volumes of given daemonset
+func GetDaemonSetVolumes(item interface{}) []v1.Volume {
+	return item.(v1beta1.DaemonSet).Spec.Template.Spec.Volumes
+}
+
+// GetStatefulsetVolumes returns the Volumes of given statefulSet
+func GetStatefulsetVolumes(item interface{}) []v1.Volume {
+	return item.(apps_v1beta1.StatefulSet).Spec.Template.Spec.Volumes
+}

internal/pkg/constants/annotations.go

@@ -5,4 +5,6 @@ const (
 	ConfigmapUpdateOnChangeAnnotation = "configmap.reloader.stakater.com/reload"
 	// SecretUpdateOnChangeAnnotation is an annotation to detect changes in secrets
 	SecretUpdateOnChangeAnnotation = "secret.reloader.stakater.com/reload"
+	// ReloaderAutoAnnotation is an annotation to detect changes in secrets
+	ReloaderAutoAnnotation = "reloader.stakater.com/auto"
 )

internal/pkg/constants/enums.go

@@ -0,0 +1,15 @@
+package constants
+
+// Result is a status for deployment update
+type Result int
+
+const (
+	// Updated is returned when environment variable is created/updated
+	Updated Result = 1 + iota
+	// NotUpdated is returned when environment variable is found but had value equals to the new value
+	NotUpdated
+	// NoEnvVarFound is returned when no environment variable is found
+	NoEnvVarFound
+	// NoContainerFound is returned when no environment variable is found
+	NoContainerFound
+)

internal/pkg/controller/controller.go

@@ -64,7 +64,7 @@ func (c *Controller) Update(old interface{}, new interface{}) {
 
 // Delete function to add an object to the queue in case of deleting a resource
 func (c *Controller) Delete(old interface{}) {
-	logrus.Infof("Resource deletion has been detected but no further implementation found to take action")
+	// Todo: Any future delete event can be handled here
 }
 
 //Run function for controller which handles the queue