NodeJS Service is not reachable on Kubernete (GCP) - node.js

Question

I have a true roadblock here and I have not found any solutions so far. Ultimately, my deployed NodeJS + Express server is not reachable when deploying to a Kubernete cluster on GCP. I followed the guide & example, nothing seems to work.
The cluster, node and service are running just fine and don't have any issues. Furthermore, it works just fine locally when running it with Docker.
Here's my Node YAML:
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
deployment.kubernetes.io/revision: "1"
creationTimestamp: 2019-08-06T04:13:29Z
generation: 1
labels:
run: nodejsapp
name: nodejsapp
namespace: default
resourceVersion: "23861"
selfLink: /apis/apps/v1/namespaces/default/deployments/nodejsapp
uid: 8b6b7ac5-b800-11e9-816e-42010a9600de
spec:
progressDeadlineSeconds: 2147483647
replicas: 1
revisionHistoryLimit: 10
selector:
matchLabels:
run: nodejsapp
strategy:
rollingUpdate:
maxSurge: 1
maxUnavailable: 1
type: RollingUpdate
template:
metadata:
creationTimestamp: null
labels:
run: nodejsapp
spec:
containers:
- image: gcr.io/${project}/nodejsapp:latest
imagePullPolicy: Always
name: nodejsapp
ports:
- containerPort: 5000
protocol: TCP
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
dnsPolicy: ClusterFirst
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
terminationGracePeriodSeconds: 30
status:
availableReplicas: 1
conditions:
- lastTransitionTime: 2019-08-06T04:13:29Z
lastUpdateTime: 2019-08-06T04:13:29Z
message: Deployment has minimum availability.
reason: MinimumReplicasAvailable
status: "True"
type: Available
observedGeneration: 1
readyReplicas: 1
replicas: 1
updatedReplicas: 1
Service YAML:
apiVersion: v1
kind: Service
metadata:
creationTimestamp: 2019-08-06T04:13:34Z
labels:
run: nodejsapp
name: nodejsapp
namespace: default
resourceVersion: "25444"
selfLink: /api/v1/namespaces/default/services/nodejsapp
uid: 8ef81536-b800-11e9-816e-42010a9600de
spec:
clusterIP: XXX.XXX.XXX.XXX
externalTrafficPolicy: Cluster
ports:
- nodePort: 32393
port: 80
protocol: TCP
targetPort: 5000
selector:
run: nodejsapp
sessionAffinity: None
type: LoadBalancer
status:
loadBalancer:
ingress:
- ip: XXX.XXX.XXX.XXX
The NodeJS server is configured to run on Port 5000. I tried doing no port-forwarding as well but not a difference in the result.
Any help is much appreciated.
UPDATE:
I used this guide and followed the instructions: https://cloud.google.com/kubernetes-engine/docs/tutorials/hello-app
UPDATE 2:
FINALLY - figured it out. I'm not sure why this is not mentioned anywhere but you have to create an Ingress that routes the traffic to the pod accordingly.
Here's the example config:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
annotations:
ingress.kubernetes.io/backends: '{"k8s-be-32064--abfe1f07378017e9":"HEALTHY"}'
ingress.kubernetes.io/forwarding-rule: k8s-fw-default-nodejsapp--abfe1f07378017e9
ingress.kubernetes.io/target-proxy: k8s-tp-default-nodejsapp--abfe1f07378017e9
ingress.kubernetes.io/url-map: k8s-um-default-nodejsapp--abfe1f07378017e9
creationTimestamp: 2019-08-06T18:59:15Z
generation: 1
name: nodejsapp
namespace: default
resourceVersion: "171168"
selfLink: /apis/extensions/v1beta1/namespaces/default/ingresses/versapay-api
uid: 491cd248-b87c-11e9-816e-42010a9600de
spec:
backend:
serviceName: nodejsapp
servicePort: 80
status:
loadBalancer:
ingress:
- ip: XXX.XXX.XXX

Answer 1

Adding it as an answer as need to include image (But not necessarily an answer):
As shown in the image, besides your backend service, a green tick should be visible
Probable Solution:
In your NodeJsApp, please add the following base URL .i.e.,
When the application is started locally, http://localhost:5000/ should return a 200 status code (With ideally Server is running... or some message)
And also, if path based routing is enabled, another base URL is also required:
http://localhost:5000/<nodeJsAppUrl>/ should also return 200 status code.
Above URLs are required for health check of both LoadBalancer and Backend Service and redeploy the service.
Please let me know if the above solution doesn't fix the said issue.

Answer 2

You need an intermediate service to internally expose your deployment.
Right now, you have a set of pods grouped in a deployment and a load balancer exposed in your cluster but you need to link them with an additional service.
You can try using a NodePort like the following:
apiVersion: v1
kind: Service
metadata:
name: nodejsapp-nodeport
spec:
selector:
run: nodejsapp
ports:
- name: default
protocol: TCP
port: 32393
targetPort: 5000
type: NodePort
This NodePort service is in between your Load Balancer and the pods in your deployment, targeting them in port 5000 and exposing port 32393 (as per your settings in the original question, you can change it).
From here, you can redeploy your Load Balancer to target the previous NodePort. This way, you can reach your NodeJS app via port 80 from your load balancer public address.
apiVersion: v1
kind: Service
metadata:
name: nodejs-lb
spec:
selector:
run: nodejsapp
ports:
- name: default
protocol: TCP
port: 80
targetPort: 32393
type: LoadBalancer
The whole scenario would look like this:
publicy exposed address --> LoadBalancer --> | NodePort --> Deployment --> Pods