Moleculer k8 depoyment

moleculer-k8.md

Create a cluster on GKE:

gcloud container clusters create backend --num-nodes=2 --machine-type n1-standard-4

Get credentials:

gcloud container clusters get-credentials backend

Build the docker image:

docker build -t gcr.io/your-company/image:v1 .

Push the image to GCR:

docker push gcr.io/your-company/image:v1

Deploy the application:

kubectl apply -f moleculer-k8.yml

Basic deployment script:

#!/bin/bash
** replace gcr.io/you-company/image:v1 in the k8 yml with $DEPLOYMENT_IMAGE **
HASH=$(git rev-parse HEAD)
IMAGE=gcr.io/your-company/image:$HASH
echo "Hash: $HASH"
echo "Image: $IMAGE"
read -p "Continue? " -n 1 -r
echo
if [[ $REPLY =~ ^[Yy]$ ]]
then
    docker build --no-cache -t $IMAGE .
    docker push $IMAGE
    export DEPLOYMENT_IMAGE=$IMAGE
    envsubst < k8.yml | kubectl apply -f -
fi

Below is an example of the k8 yml file...

apiVersion: v1
kind: Service
metadata:
  name: mongo
  labels:
    name: mongo
spec:
  ports:
  - port: 27017
    targetPort: 27017
  selector:
   name: mongo
---
apiVersion: v1
kind: Service
metadata:
  name: nats
  labels:
    name: nats
spec:
  ports:
    - port: 4222
      targetPort: 4222
  selector:
    name: nats
---
apiVersion: v1
kind: Service
metadata:
  name: api-service
spec:
  type: NodePort
  ports:
  - port: 80
    name: http
    targetPort: 3000
    protocol: TCP
  - port: 443
    name: https
    targetPort: 3000
    protocol: TCP
  selector:
    app: api
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: api-ingress
  annotations:
    kubernetes.io/ingress.global-static-ip-name: "name-of-static-ip"
    kubernetes.io/ingress.class: "gce"
spec:
  rules:
  - http:
      paths:
      - path: /*
        backend:
          serviceName: api-service
          servicePort: 80

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: mongo
  labels:
    name: mongo
spec:
  replicas: 1
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        name: mongo
    spec:
      containers:
      - image: mongo
        name: mongo
        ports:
        - containerPort: 27017
        resources: {}
        volumeMounts:
        - mountPath: /data/db
          name: mongo-data
      restartPolicy: Always
      volumes:
      - name: mongo-data
        persistentVolumeClaim:
          claimName: mongo-data
status: {}
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mongo-data
  labels:
    name: mongo-data
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 100Mi
status: {}
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: nats
  labels:
    name: nats
spec:
  replicas: 1
  strategy: {}
  template:
    metadata:
      labels:
        name: nats
    spec:
      containers:
      - image: nats
        name: nats
        ports:
        - containerPort: 4222
        resources: {}
      restartPolicy: Always
status: {}
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: api
  labels:
    name: api
spec:
  replicas: 1
  template:
    metadata:
      name: api
      labels:
        app: api
        name: api
    spec:
      containers:
      - name: api
        image: gcr.io/you-company/image:v1
        imagePullPolicy: Always
        ports:
          - name: api
            containerPort: 3000
        env:
        - name: LOGGER
          value: "true"
        - name: LOGLEVEL
          value: info
        - name: MONGO_URI
          value: mongodb://mongo/dbname
        - name: PORT
          value: "3000"
        - name: SERVICES
          value: services/api.service.js
        - name: TRANSPORTER
          value: nats://nats:4222
      restartPolicy: Always
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: someotherservice
  labels:
    name: someotherservice
spec:
  replicas: 1
  template:
    metadata:
      labels:
        name: someotherservice
    spec:
      containers:
      - name: someotherservice
        image: gcr.io/your-company/image:v1
        imagePullPolicy: Always
        env:
        - name: NODEID
          value: 'node-someotherservice'
        - name: LOGGER
          value: "true"
        - name: LOGLEVEL
          value: info
        - name: MONGO_URI
          value: mongodb://mongo/dbname
        - name: SERVICES
          value: services/someother.service.js
        - name: TRANSPORTER
          value: nats://nats:4222
      restartPolicy: Always