I'm unable to access k8's Service through Postman - scala

Question

I created a simple scala application, that uses akkaHttp to add user data and get user data, akkaHttp is running on "localhost" and has port "8080".
Http().newServerAt("localhost", 8080).bind(route)
After that I create a "deployment" and "service" given below:
deployment.yaml
`apiVersion: apps/v1
kind: Deployment
metadata:
name: docker-deployment
spec:
replicas: 2
selector:
matchLabels:
app: docker-label
template:
metadata:
name: docker-pod
labels:
app: docker-label
spec:
containers:
- name: docker-container
image: akkahttp-k8s:0.1.0-SNAPSHOT
ports:
- containerPort: 80
`
service.yaml
`apiVersion: v1
kind: Service
metadata:
name: docker-service
spec:
type: NodePort
selector:
app: docker-label
ports:
- port: 8080
targetPort: 80
nodePort: 32100`
My service and deployment are in "running" state and showing no error.
pods:
NAME READY STATUS RESTARTS AGE
docker-deployment-79756959c6-rdknq 1/1 Running 0 6s
docker-deployment-79756959c6-thjzt 1/1 Running 0 6s
service:
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
docker-service NodePort 10.103.170.1 <none> 8080:32100/TCP 4m35s
But when I try to access the service through the "Postman" it throughs an error " Error: connect ECONNREFUSED 192.168.49.2:32100 ".
When I tried to use " port-forward docker-deployment-79756959c6-rdknq 8080:8080 " then I can interact with my pod successfully through postman using " http://localhost:8080 ". Why I'm unable to interact with my pod through service ? where I'm doing mistake ?.
Kindly help me to deal with this issue.

Answer 1

I'm using a generic container that listens on 8080:
https://github.com/kubernetes-up-and-running/kuard
deployment.yaml:
apiVersion: apps/v1
kind: Deployment
metadata:
name: docker-deployment
spec:
replicas: 2
selector:
matchLabels:
app: docker-label
template:
metadata:
name: docker-pod
labels:
app: docker-label
spec:
containers:
- name: docker-container
image: gcr.io/kuar-demo/kuard-amd64:blue
ports:
- containerPort: 8080
NOTE containerPort: 8080
and service.yaml:
apiVersion: v1
kind: Service
metadata:
name: docker-service
spec:
type: NodePort
selector:
app: docker-label
ports:
- port: 8080
targetPort: 8080
NOTE targetPort: 8080 (matches the Pod's port which is the container's port)
Then:
NAMESPACE="75488823"
kubectl create namespace ${NAMESPACE}
kubectl apply --filename=./deployment.yaml \
--namespace=${NAMESPACE}
kubectl apply --file=./service.yaml \
--namespace=${NAMESPACE}
Then access the service using kubectl port-forward
kubectl port-forward deployment/docker-deployment \
--namespace=${NAMESPACE} \
8080:8080
And:
curl \
--silent \
--get \
--output /dev/null \
--write-out '%{response_code}' \
http://localhost:8080
Should yield 200 (success)
Then access the services using any (!) nodes' IP address. You may need to determine the {HOST} value for yourself. You want any node's public IP address.
# Get any nodes' IP
HOST=$(\
kubectl get nodes \
--output=jsonpath="{.items[0].status.addresses[0].address}"
# Get the service's `nodePort`
PORT=$(\
kubectl get service/docker-service \
--namespace=${NAMESPACE} \
--output=jsonpath="{.spec.ports[0].nodePort}")
curl \
--silent \
--get \
--output /dev/null \
--write-out '%{response_code}' \
http://${HOST}:${PORT}
Should also yield 200 (success).
Tidy:
kubectl delete namespace/${NAMESPACE}