F - have reaper use sorting strategies

examples/pod-sorting-strategy.yml

@@ -0,0 +1,85 @@
+# example configuration with permission for running pod-reaper against
+# an entire cluster
+
+---
+# namespace for the reaper
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: reaper
+
+---
+# service account for running pod-reaper
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: pod-reaper-service-account
+  namespace: reaper
+
+---
+# minimal permissions required for running pod-reaper at cluster level
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: pod-reaper-cluster-role
+rules:
+- apiGroups: [""]
+  resources: ["pods"]
+  verbs: ["list", "delete"]
+
+---
+# binding the above cluster role (permissions) to the above service account
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: pod-reaper-role-binding
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: pod-reaper-cluster-role
+subjects:
+- kind: ServiceAccount
+  name: pod-reaper-service-account
+  namespace: reaper
+
+---
+# a basic pod-reaper deployment
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: pod-reaper
+  namespace: reaper # namespace matches above
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: pod-reaper
+  template:
+    metadata:
+      labels:
+        app: pod-reaper
+    spec:
+      serviceAccount: pod-reaper-service-account # service account from above
+      containers:
+      - name: chaos
+        image: brianberzins/pod-reaper:alpha
+        resources:
+          limits:
+            cpu: 30m
+            memory: 30Mi
+          requests:
+            cpu: 20m
+            memory: 20Mi
+        env:
+          - name: EXCLUDE_LABEL_KEY
+            value: "tier"
+          - name: EXCLUDE_LABEL_VALUES
+            value: "control-plane"
+          - name: SCHEDULE
+            value: "@every 20s"
+          - name: CHAOS_CHANCE
+            value: "1"
+          - name: MAX_PODS
+            value: "1"
+          - name: POD_SORTING_STRATEGY
+            value: "oldest-first"

reaper/options.go

@@ -43,6 +43,7 @@ type options struct {
 	annotationRequirement *labels.Requirement
 	dryRun                bool
 	maxPods               int
+	podSortingStrategy    func([]v1.Pod)
 	rules                 rules.Rules
 	evict                 bool
 }
@@ -235,44 +236,37 @@ func evict() (bool, error) {
 
 func loadOptions() (options options, err error) {
 	options.namespace = namespace()
-	options.gracePeriod, err = gracePeriod()
-	if err != nil {
+	if options.gracePeriod, err = gracePeriod(); err != nil {
 		return options, err
 	}
 	options.schedule = schedule()
-	options.runDuration, err = runDuration()
-	if err != nil {
+	if options.runDuration, err = runDuration(); err != nil {
 		return options, err
 	}
-	options.labelExclusion, err = labelExclusion()
-	if err != nil {
+	if options.labelExclusion, err = labelExclusion(); err != nil {
 		return options, err
 	}
-	options.labelRequirement, err = labelRequirement()
-	if err != nil {
+	if options.labelRequirement, err = labelRequirement(); err != nil {
 		return options, err
 	}
-	options.annotationRequirement, err = annotationRequirement()
-	if err != nil {
+	if options.annotationRequirement, err = annotationRequirement(); err != nil {
 		return options, err
 	}
-	options.dryRun, err = dryRun()
-	if err != nil {
+	if options.dryRun, err = dryRun(); err != nil {
 		return options, err
 	}
-	options.maxPods, err = maxPods()
-	if err != nil {
+	if options.maxPods, err = maxPods(); err != nil {
 		return options, err
 	}
-
-	options.evict, err = evict()
-	if err != nil {
+	if options.podSortingStrategy, err = podSortingStrategy(); err != nil {
+		return options, err
+	}
+	if options.evict, err = evict(); err != nil {
 		return options, err
 	}
 
 	// rules
-	options.rules, err = rules.LoadRules()
-	if err != nil {
+	if options.rules, err = rules.LoadRules(); err != nil {
 		return options, err
 	}
 	return options, nil

reaper/reaper.go

@@ -60,9 +60,7 @@ func (reaper reaper) getPods() *v1.PodList {
 		listOptions.LabelSelector = selector.String()
 	}
 	podList, err := pods.List(listOptions)
-
-	// get a sorting strategy
-	// sort by that strategy
+	reaper.options.podSortingStrategy(podList.Items)
 
 	if err != nil {
 		logrus.WithError(err).Panic("unable to get pods from the cluster")