Add generate_example_manifest.go

Add script to generate manifest of pod with certain # PVs

Add to --node-affinity flag to generate_example_manifest.go

hack/device_slot_test.tmpl

@@ -0,0 +1,51 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: device-limit-tester-{{ len .Volumes }}-volumes
+spec:
+  affinity:
+    nodeAffinity:
+      requiredDuringSchedulingIgnoredDuringExecution:
+        nodeSelectorTerms:
+        - matchExpressions:
+          - key: {{ .NodeAffinityKey }}
+            operator: In
+            values:
+            - {{ .NodeAffinityValue }}
+  containers:
+  - name: device-limit-tester-{{ len .Volumes }}-volumes
+    image: centos
+    command: ["/bin/sh"]
+    args: ["-c", "while true; do echo $(date -u) >> /data/out.txt; sleep 5; done"]
+    volumeMounts:
+{{- range $index, $value := .Volumes }}
+    - name: persistent-storage-{{ $index }}
+      mountPath: /data-{{ $index }}
+{{- end }}
+  volumes:
+{{- range $index, $value := .Volumes }}
+    - name: persistent-storage-{{ $index }}
+      persistentVolumeClaim:
+        claimName: ebs-claim-{{ $index }}
+{{- end }}
+---
+{{- range $index, $value := .Volumes }}
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: ebs-claim-{{ $index }}
+spec:
+  accessModes:
+    - ReadWriteOnce
+  storageClassName: ebs-sc
+  resources:
+    requests:
+      storage: 4Gi
+---
+{{- end }}
+apiVersion: storage.k8s.io/v1
+kind: StorageClass
+metadata:
+  name: ebs-sc
+provisioner: ebs.csi.aws.com
+volumeBindingMode: WaitForFirstConsumer

hack/generate_example_manifest.go

@@ -0,0 +1,55 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+	"text/template"
+)
+
+type Manifest struct {
+	NodeAffinityKey   string
+	NodeAffinityValue string
+	Volumes           []int
+}
+
+func main() {
+	// Parse Command-Line args & flags
+	nodeAffinityPtr := flag.String("node-affinity", "", "node affinity for pod in form of 'key:value'")
+	volumeCountPtr := flag.Int("volume-count", 2, "amount of Volumes to provision")
+	flag.Parse()
+
+	nodeAffinityKey, nodeAffinityValue := parseNodeAffinityFlag(nodeAffinityPtr)
+
+	manifest := Manifest{
+		NodeAffinityKey:   nodeAffinityKey,
+		NodeAffinityValue: nodeAffinityValue,
+		Volumes:           make([]int, *volumeCountPtr),
+	}
+
+	// Generate manifest to stdout from template file
+	var tmplFile = "device_slot_test.tmpl"
+	tmpl, err := template.New(tmplFile).ParseFiles(tmplFile)
+	if err != nil {
+		panic(err)
+	}
+	err = tmpl.Execute(os.Stdout, manifest)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func parseNodeAffinityFlag(nodeAffinityPtr *string) (string, string) {
+	nodeAffinityKey := ""
+	nodeAffinityValue := ""
+	if len(*nodeAffinityPtr) > 0 {
+		nodeAffinity := strings.Split(*nodeAffinityPtr, ":")
+		if len(nodeAffinity) != 2 {
+			panic(fmt.Errorf("flag '--node-affinity' must take the form 'key:value'"))
+		}
+		nodeAffinityKey = nodeAffinity[0]
+		nodeAffinityValue = nodeAffinity[1]
+	}
+	return nodeAffinityKey, nodeAffinityValue
+}