Example of string templating within Jsonnet

main.jsonnet

{
    template: (importstr "template.yaml") % {
        name: "rabbitmq",
        image: "whatever",
        cookie: "XXXX",
        data_volume: std.toString({ name: "thing", foo: [1, 2, 3] }),
        nodes: std.toString(['rabbit@rabbitmq-%s' % shard_name for shard_name in [1, 2, 3]]),
    },
}

otuput.json

{
   "template": "---\napiVersion: v1\nkind: ReplicationController\nmetadata:\n  labels:\n    k8s-app: rabbitmq\n  name: rabbitmq\nspec:\n  replicas: 1\n  selector:\n    k8s-app: rabbitmq\n    shard: \"rabbitmq\"\n  template:\n    metadata:\n      labels:\n        k8s-app: rabbitmq\n        shard: \"rabbitmq\"\n    spec:\n      containers:\n        - image: \"whatever\"\n          name: rabbitmq\n          ports:\n            - containerPort: 5672\n              name: rmq\n            - containerPort: 15672\n              name: dash\n            - containerPort: 4369\n              name: erlang\n            - containerPort: 25672\n              name: cluster\n          resources:\n            limits:\n              cpu: 500m\n              memory: 2G\n          env:\n            - name: RABBITMQ_CLUSTER_NODES\n              value: \"[\"rabbit@rabbitmq-1\", \"rabbit@rabbitmq-2\", \"rabbit@rabbitmq-3\"]\"\n            - name: RABBITMQ_ERLANG_COOKIE\n              value: \"XXXX\"\n            - name: RABBITMQ_HOSTNAME\n              value: \"rabbitmq-rabbitmq\"\n            - name: RABBITMQ_NODENAME\n              value: \"rabbit@rabbitmq-rabbitmq\"\n          volumeMounts:\n            - mountPath: '/var/lib/rabbitmq'\n              name: 'varlibrabbitmq'\n      volumes:\n        - {\"foo\": [1, 2, 3], \"name\": \"thing\"}\n\n"
}

template.yaml

---
apiVersion: v1
kind: ReplicationController
metadata:
  labels:
    k8s-app: rabbitmq
  name: rabbitmq
spec:
  replicas: 1
  selector:
    k8s-app: rabbitmq
    shard: "%(name)s"
  template:
    metadata:
      labels:
        k8s-app: rabbitmq
        shard: "%(name)s"
    spec:
      containers:
        - image: "%(image)s"
          name: rabbitmq
          ports:
            - containerPort: 5672
              name: rmq
            - containerPort: 15672
              name: dash
            - containerPort: 4369
              name: erlang
            - containerPort: 25672
              name: cluster
          resources:
            limits:
              cpu: 500m
              memory: 2G
          env:
            - name: RABBITMQ_CLUSTER_NODES
              value: %(nodes)s
            - name: RABBITMQ_ERLANG_COOKIE
              value: "%(cookie)s"
            - name: RABBITMQ_HOSTNAME
              value: "rabbitmq-%(name)s"
            - name: RABBITMQ_NODENAME
              value: "rabbit@rabbitmq-%(name)s"
          volumeMounts:
            - mountPath: '/var/lib/rabbitmq'
              name: 'varlibrabbitmq'
      volumes:
        - %(data_volume)s