Unable to get ClusterIP service url from minikube - kubernetes

Question

I have created a ClusterIP service according to configuration files below, however I can't seem to get the URL from minikube for that service
k create -f service-cluster-definition.yaml
➜ minikube service myapp-frontend --url
😿 service default/myapp-frontend has no node port
And if I try to add NodePort into the ports section of service-cluster-definition.yaml it complains with error, that such key is deprecated.
What am I missing or doing wrong?
service-cluster-definition.yaml
apiVersion: v1
kind: Service
metadata:
name: myapp-frontend
spec:
type: ClusterIP
ports:
- targetPort: 80
port: 80
selector:
app: myapp
type: etl
deployment-definition.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp-deployment
labels:
app: myapp
env: experiment
type: etl
spec:
template:
metadata:
name: myapp-pod
labels:
app: myapp
env: experiment
type: etl
spec:
containers:
- name: nginx-container
image: nginx:1.7.1
replicas: 3
selector:
matchLabels:
type: etl
➜ k get pods --selector="app=myapp,type=etl" -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
myapp-deployment-59856c4487-2g9c7 1/1 Running 0 45m 172.17.0.9 minikube <none> <none>
myapp-deployment-59856c4487-mb28z 1/1 Running 0 45m 172.17.0.4 minikube <none> <none>
myapp-deployment-59856c4487-sqxqg 1/1 Running 0 45m 172.17.0.8 minikube <none> <none>
(⎈ |minikube:default)
Projects/experiments/kubernetes
➜ k version
Client Version: version.Info{Major:"1", Minor:"17", GitVersion:"v1.17.3", GitCommit:"06ad960bfd03b39c8310aaf92d1e7c12ce618213", GitTreeState:"clean", BuildDate:"2020-02-11T18:14:22Z", GoVersion:"go1.13.6", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"17", GitVersion:"v1.17.3", GitCommit:"06ad960bfd03b39c8310aaf92d1e7c12ce618213", GitTreeState:"clean", BuildDate:"2020-02-11T18:07:13Z", GoVersion:"go1.13.6", Compiler:"gc", Platform:"linux/amd64"}
(⎈ |minikube:default)

Answer 1

First let's clear some concepts from Documentation:
ClusterIP: Exposes the Service on a cluster-internal IP.
Choosing this value makes the Service only reachable from within the cluster.
NodePort: Exposes the Service on each Node’s IP at a static port (the NodePort).
You’ll be able to contact the NodePort Service, from outside the cluster, by requesting NodeIP:NodePort.
Question 1:
I have created a ClusterIP service according to configuration files below, however I can't seem to get the URL from minikube for that service.
Since Minikube is a virtualized environment on a single host we tend to forget that the cluster is isolated from the host computer. If you set a service as ClusterIP, Minikube will not give external access.
Question 2:
And if I try to add NodePort into the ports section of service-cluster-definition.yaml it complains with error, that such key is deprecated.
Maybe you were pasting on the wrong position. You should just substitute the field type: ClusterIP for type: NodePort. Here is the correct form of your yaml:
apiVersion: v1
kind: Service
metadata:
name: myapp-frontend
spec:
type: NodePort
ports:
- targetPort: 80
port: 80
selector:
app: myapp
type: etl
Reproduction:
user#minikube:~$ kubectl apply -f deployment-definition.yaml
deployment.apps/myapp-deployment created
user#minikube:~$ kubectl get pods
NAME READY STATUS RESTARTS AGE
myapp-deployment-59856c4487-7dw6x 1/1 Running 0 5m11s
myapp-deployment-59856c4487-th7ff 1/1 Running 0 5m11s
myapp-deployment-59856c4487-zvm5f 1/1 Running 0 5m11s
user#minikube:~$ kubectl apply -f service-cluster-definition.yaml
service/myapp-frontend created
user#minikube:~$ kubectl get service myapp-frontend
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
myapp-frontend NodePort 10.101.156.113 <none> 80:32420/TCP 3m43s
user#minikube:~$ minikube service list
|-------------|----------------|-----------------------------|-----|
| NAMESPACE | NAME | TARGET PORT | URL |
|-------------|----------------|-----------------------------|-----|
| default | kubernetes | No node port | |
| default | myapp-frontend | http://192.168.39.219:32420 | |
| kube-system | kube-dns | No node port | |
|-------------|----------------|-----------------------------|-----|
user#minikube:~$ minikube service myapp-frontend --url
http://192.168.39.219:32420
user#minikube:~$ curl http://192.168.39.219:32420
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
...{{output suppressed}}...
As you can see, with the service set as NodePort the minikube start serving the app using MinikubeIP:NodePort routing the connection to the matching pods.
Note that nodeport will be chosen by default between 30000:32767
If you have any question let me know in the comments.

Answer 2

To access inside cluster, do kubectl get svc to get the cluster ip or use the service name directly.
To access outside cluster, you can use NodePort as service type.