How to deploy a node.js with redis on kubernetes?

Question

I have a very simple node.js application (HTTP service), which \"talks\" to redis. I want to create a deployment and run it with minikube.

From my understanding, I n

Answer 1

I agree with all of the previous answers. I'm just trying to things more simple by executing a single command.

First, create necessary manifests for redis in a file say redis.yaml and service to expose it outside.

apiVersion: v1
kind: Service
metadata:
  name: redis
  labels:
    app: node-redis
spec:
  ports:
  - name: redis
    port: 6379
    targetPort: 6379
  type: NodePort
  selector:
    app: node-redis
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis
spec:
  selector:
    matchLabels:
      app: node-redis
  replicas: 1
  template:
    metadata:
      labels:
        app: node-redis
    spec:
      containers:
      - name: redis
        image: redis:latest
        imagePullPolicy: IfNotPresent
        ports:
        - containerPort: 6379
        # data volume where redis writes data
        volumeMounts:
        - name: data
          mountPath: /data
          readOnly: false
      volumes:
      - name: data
        persistentVolumeClaim:
          claimName: redis-data
---
# data volume
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: redis-data
  labels:
    app: node-redis
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 100Mi

Next put manifests for your app in another file say my-app.yaml. Here i put the volume field so that you can use the data that stored by redis.

apiVersion: v1
kind: Pod
metadata:
  name: my-app
  labels:
    app: node-redis
spec:
  containers:
  - name: my-app
    image: my-app:latest
    ports:
    - containerPort: 8080
    # data volume from where my-app read data those are written by redis
    volumeMounts:
    - name: data
      mountPath: /data
      readOnly: false
  volumes:
  - name: data
    persistentVolumeClaim:
      claimName: redis-data

Now we can use the following bash file my-app.sh.

#!/bin/bash

kubectl create -f redis.yaml

pod_name=$(kubectl get po -l app=node-redis | grep app-with-redis | awk '{print $1}')

# check whether redis server is ready or not
while true; do
  pong=$(kubectl exec -it $pod_name -c redis redis-cli ping)
  if [[ "$pong" == *"PONG"* ]]; then
    echo ok;
    break
  fi
done

kubectl create -f my-app.yaml

Just run chmod +x my-app.sh; ./my-app.sh to deploy. To get the url run minikube service redis --url. You can similarly get the url for your app. The only thing is you need a nodePort type service for your app to access it from outside of the cluster.

So, everything is in your hand now.