Migrating Heroku Angular app to DO Kubernetes

At present I am running an Angular client app and a Nodejs/Express API on Heroku, and a MongoDB on MongoDB Inc. I have decided to migrate my project to Kubernetes, and selected DigitalOcean (mainly because they’re neither Google nor Amazon).

I have successfully migrated the API to a kubernetes deployment. Following an excellent DO tutorial, I was able to connect the deployment to my domain name through Nginx Ingress and secure it with Cert-Manager. This was the tutorial I followed: https://www.digitalocean.com/community/tutorials/how-to-set-up-an-nginx-ingress-on-digitalocean-kubernetes-using-helm

I am now working to migrate the Angular client to a k8s deployment and could use advice on troubleshooting. I experienced problems containerizing the app with docker and resolved those by switching the package manager from npm to yarn. The container now successfully runs in a pod (status is ‘running’), and I’ve connected it to my ingress controller. When I try to connect, however, I get the 502 Bad Gateway error. I suspect I’m routing the port incorrectly. Angular apps default to port 4200, and I redirect those to port 80, just as with the tutorial, above.

Here are my yaml files for the deployment and for Ingress. There are four DNS routes. hw1 and hw2 are from the tutorial and are working fine. api is my API and is working fine. I have not included those yaml files. The DNS route for pvg does not work. It points to the “markwilx” deployment. I welcome any suggestion for proceeding with troubleshooting.

Thanks in advance, Mark

Deployment:

---
apiVersion: v1
kind: Service
metadata:
  name: markwilx
spec:
  type: ClusterIP
  ports:
    - port: 80
      targetPort: 4200
  selector:
    app: markwilx
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: markwilx
spec:
  replicas: 1
  selector:
    matchLabels:
      app: markwilx
  template:
    metadata:
      labels:
        app: markwilx
    spec:
      containers:
      - name: nginx
        image: registry.digitalocean.com/XXXXXXXX/markwilx:0.3.1
        ports:
        - containerPort: 4200
          protocol: TCP

Ingress:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: hello-kubernetes-ingress
  annotations:
    kubernetes.io/ingress.class: nginx
    cert-manager.io/cluster-issuer: letsencrypt-prod
spec:
  tls:
  - hosts:
    - hw1.XXXXXXXXX.org    # This is working
    - hw2.XXXXXXXXX.org    # This is working
    - api.XXXXXXXXX.org    # This is working
    - pvg.XXXXXXXXX.org    # This is NOT working
    secretName: hello-kubernetes-tls
  rules:
  - host: "hw1.XXXXXXXXX.org"
    http:
      paths:
      - pathType: Prefix
        path: "/"
        backend:
          service:
            name: hello-kubernetes-first
            port:
              number: 80
  - host: "hw2.XXXXXXXXX.org"
    http:
      paths:
      - pathType: Prefix
        path: "/"
        backend:
          service:
            name: hello-kubernetes-second
            port:
              number: 80
  - host: "api.XXXXXXXXX.org"
    http:
      paths:
      - pathType: Prefix
        path: "/"
        backend:
          service:
            name: mwx-api
            port:
              number: 80
  - host: "pvg.XXXXXXXXX.org"
    http:
      paths:
      - pathType: Prefix
        path: "/"
        backend:
          service:
            name: markwilx
            port:
              number: 80