Assume I have this manifest:

apiVersion: batch/v1
kind: Job
metadata:
  name: initialize-assets-fixtures
spec:
  template:
    spec:
      initContainers:
      - name: wait-for-minio
        image: bitnami/minio-client
        env:
          - name: MINIO_SERVER_ACCESS_KEY
            valueFrom:
              secretKeyRef:
                name: minio
                key: access-key
          - name: MINIO_SERVER_SECRET_KEY
            valueFrom:
              secretKeyRef:
                name: minio
                key: secret-key
          - name: MINIO_SERVER_HOST
            value: minio
          - name: MINIO_SERVER_PORT_NUMBER
            value: "9000"
          - name: MINIO_ALIAS
            value: minio
        command: 
          - /bin/sh
          - -c 
          - |
            mc config host add ${MINIO_ALIAS} http://${MINIO_SERVER_HOST}:${MINIO_SERVER_PORT_NUMBER} ${MINIO_SERVER_ACCESS_KEY} ${MINIO_SERVER_SECRET_KEY}
      containers:
      - name: initialize-assets-fixtures
        image: bitnami/minio
        env:
          - name: MINIO_SERVER_ACCESS_KEY
            valueFrom:
              secretKeyRef:
                name: minio
                key: access-key
          - name: MINIO_SERVER_SECRET_KEY
            valueFrom:
              secretKeyRef:
                name: minio
                key: secret-key
          - name: MINIO_SERVER_HOST
            value: minio
          - name: MINIO_SERVER_PORT_NUMBER
            value: "9000"
          - name: MINIO_ALIAS
            value: minio
        command:
          - /bin/sh
          - -c
          - |
            mc config host add ${MINIO_ALIAS} http://${MINIO_SERVER_HOST}:${MINIO_SERVER_PORT_NUMBER} ${MINIO_SERVER_ACCESS_KEY} ${MINIO_SERVER_SECRET_KEY}

            for category in `ls`; do
              for f in `ls $category/*` ; do
                mc cp $f ${MINIO_ALIAS}/$category/$(basename $f)
              done
            done
      restartPolicy: Never

You see I have here one initContainer and one container. In both containers, I have the same configuration, i.e. the same env section.

Assume I have yet another Job manifest where I use the very same env section again.

It's a lot of duplicated configuration that I bet I can simplify drastically, but I don't know how to do it. Any hint? Any link to some documentation? After some googling, I was not able to come up with anything useful. Maybe with kustomize, but I'm not sure. Or maybe I'm doing it the wrong way with all those environment variables, but I don't think I have a choice, depending on the service I'm using (here it's minio, but I want to do the same kind of stuff with other services which might not be as flexible as minio).