Grampsweb on kubernetes - Part 2: Common ConfigMap

Let’s improve the basic setup we did in part 1 by moving the configuration into a configmap that can be shared between Grampsweb and Celery

The ConfigMap:

A Kubernetes ConfigMap object holds non-confidential key-value pairs that can be consumed from Pods. One way of consuming it is to mount them as environment variables.

Continuing the setup for Grampsweb on Kubernetes, we can improve it by putting all the environment variables defined in docker-compose into a new ConfigMap definition:

apiVersion: v1
kind: ConfigMap
metadata:
  name: grampsweb
data:
  GRAMPSWEB_CELERY_CONFIG__broker_url: "redis://grampsweb-redis:6379/0"
  GRAMPSWEB_CELERY_CONFIG__result_backend: "redis://grampsweb-redis:6379/0"
  GRAMPSWEB_RATELIMIT_STORAGE_URI: "redis://grampsweb-redis:6379/1"
  GRAMPSWEB_TREE: "Gramps Web"

grampsweb-configmap.yaml

Mounting the ConfigMap:

We can now replace the individual environment variable definitions in grampsweb-deployment.yaml and grampsweb-celery-deployment.yaml with an entry to mount the ConfigMap:

Grampsweb:

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: grampsweb
  name: grampsweb
spec:
  replicas: 1
  selector:
    matchLabels:
      app: grampsweb
  template:
    metadata:
      labels:
        app: grampsweb
    spec:
      containers:
        - envFrom:
          - configMapRef:
              name: grampsweb
          image: ghcr.io/gramps-project/grampsweb:latest
          name: grampsweb
          ports:
            - containerPort: 5000
              protocol: TCP
          volumeMounts:
            - mountPath: /app/users
              name: gramps-users
            - mountPath: /app/indexdir
              name: gramps-index
            - mountPath: /app/thumbnail_cache
              name: gramps-thumb-cache
            - mountPath: /app/cache
              name: gramps-cache
            - mountPath: /app/secret
              name: gramps-secret
            - mountPath: /root/.gramps/grampsdb
              name: gramps-db
            - mountPath: /app/media
              name: gramps-media
            - mountPath: /tmp
              name: gramps-tmp
      volumes:
        - name: gramps-users
          persistentVolumeClaim:
            claimName: gramps-users
        - name: gramps-index
          persistentVolumeClaim:
            claimName: gramps-index
        - name: gramps-thumb-cache
          persistentVolumeClaim:
            claimName: gramps-thumb-cache
        - name: gramps-cache
          persistentVolumeClaim:
            claimName: gramps-cache
        - name: gramps-secret
          persistentVolumeClaim:
            claimName: gramps-secret
        - name: gramps-db
          persistentVolumeClaim:
            claimName: gramps-db
        - name: gramps-media
          persistentVolumeClaim:
            claimName: gramps-media
        - name: gramps-tmp
          persistentVolumeClaim:
            claimName: gramps-tmp

grampsweb-deployment-with-configmap.yaml

Grampsweb Celery:

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: grampsweb-celery
  name: grampsweb-celery
spec:
  replicas: 1
  selector:
    matchLabels:
      app: grampsweb-celery
  template:
    metadata:
      labels:
        app: grampsweb-celery
    spec:
      containers:
        - args:
            - celery
            - -A
            - gramps_webapi.celery
            - worker
            - --loglevel=INFO
            - --concurrency=2
          envFrom:
          - configMapRef:
              name: grampsweb
          image: ghcr.io/gramps-project/grampsweb:latest
          name: grampsweb-celery
          volumeMounts:
            - mountPath: /app/users
              name: gramps-users
            - mountPath: /app/indexdir
              name: gramps-index
            - mountPath: /app/thumbnail_cache
              name: gramps-thumb-cache
            - mountPath: /app/cache
              name: gramps-cache
            - mountPath: /app/secret
              name: gramps-secret
            - mountPath: /root/.gramps/grampsdb
              name: gramps-db
            - mountPath: /app/media
              name: gramps-media
            - mountPath: /tmp
              name: gramps-tmp
      volumes:
        - name: gramps-users
          persistentVolumeClaim:
            claimName: gramps-users
        - name: gramps-index
          persistentVolumeClaim:
            claimName: gramps-index
        - name: gramps-thumb-cache
          persistentVolumeClaim:
            claimName: gramps-thumb-cache
        - name: gramps-cache
          persistentVolumeClaim:
            claimName: gramps-cache
        - name: gramps-secret
          persistentVolumeClaim:
            claimName: gramps-secret
        - name: gramps-db
          persistentVolumeClaim:
            claimName: gramps-db
        - name: gramps-media
          persistentVolumeClaim:
            claimName: gramps-media
        - name: gramps-tmp
          persistentVolumeClaim:
            claimName: gramps-tmp

grampsweb-celery-deployment-with-configmap.yaml

Deploying:

ConfigMap:

First we must deploy the ConfigMap.

Remember to deploy it to the same namespace as Grampsweb. Add the -n <namespace> flag to kubectl for all the following commands if you want to deploy to a different namespace than default

kubectl apply -f grampsweb-configmap.yaml
configmap/grampsweb created

Deploy Gampsweb Celery

kubectl apply -f grampsweb-celery-deployment-with-configmap.yaml
deployment.apps/grampsweb-celery created

Tail the logs of the container and wait for grampsweb-celery to finish start up

kubectl logs deployment/grampsweb-celery
...
<timestamp> celery@grampsweb-celery-fbf679f5c-m96md ready.

Deploy Grampsweb

kubectl apply -f grampsweb-deployment-with-configmap.yaml
deployment.apps/grampsweb created

Profit!

From now on we have a single place to put configuration for our Grampsweb instance. Remember to restart both the Celery and the Grampsweb pods every time you make changes to the ConfigMap. The ConfigMap is made for non-confidential data. For sensitive values, see part 3 where we use a secret for that.