I read that I needed to run another service in Namespace B which maps to Namespace A loadbalancer service. (You can see this service on my yaml b).

I don't want to use the external IPs given by the loadbalancers (If my scenario was replicated on the cloud using GCP/Azure/AWS/IBM cloud/OpenShift).

I deployed the next scenario using minikube v1.6.2 and Kubernetes v1.17:

Namespace a:

deployment/python-hello-world  READY: 1/1

service/python-hello-world  
TYPE: Loadbalancer CLUSTER-IP: 10.96.167.227 EXT-IP: <pending> PORTS: 80:31603/TCP

Namespace b:

deployment/python-hello-world  READY: 1/1

service/python-hello-world  
TYPE: Loadbalancer CLUSTER-IP: 10.96.67.10 EXT-IP: <pending> PORTS: 80:31595/TCP

service/connection 
TYPE: ExternalName CLUSTER-IP: <none> EXTERNAL-IP: python-hello-world-external.a.svc.cluster.local PORT: 31603/TCP

Kubernetes yaml a:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: python-hello-world
  namespace: a
spec:
  replicas: 1
  selector:
    matchLabels:
      app: python-hello-world
  template:
    metadata:
      labels:
        app: python-hello-world
    spec:
      containers:
      - name: server
        image: python-hello-world
        ports:
        - containerPort: 9090
        env:
        - name: PORT
          value: "9090"

---

apiVersion: v1
kind: Service
metadata:
  name: python-hello-world-external
  namespace: a
spec:
  type: LoadBalancer
  selector:
    app: python-hello-world
  ports:
  - name: http
    port: 80
    targetPort: 9090

Kubernetes yaml b:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: python-hello-world
  namespace: b
spec:
  replicas: 1
  selector:
    matchLabels:
      app: python-hello-world
  template:
    metadata:
      labels:
        app: python-hello-world
    spec:
      containers:
      - name: server
        image: python-hello-world
        ports:
        - containerPort: 9091
        env:
        - name: PORT
          value: "9091"

---

apiVersion: v1
kind: Service
metadata:
  name: python-hello-world-external
  namespace: b
spec:
  type: LoadBalancer
  selector:
    app: python-hello-world
  ports:
  - name: http
    port: 80
    targetPort: 9091

---

apiVersion: v1
kind: Service
metadata:
  name: connection
  namespace: b
spec:
  type: ExternalName
  externalName: python-hello-world-external.a.svc.cluster.local
  ports:
  - port: 31603

For accessing API A in my browser I ran in the terminal:

$ minikube service python-hello-world-external -n a
|-----------|-----------------------------|-------------|-----------------------------|
| NAMESPACE |            NAME             | TARGET PORT |             URL             |
|-----------|-----------------------------|-------------|-----------------------------|
| a         | python-hello-world-external | http        | http://192.168.39.196:31603 |
|-----------|-----------------------------|-------------|-----------------------------|

For accessing API B:

$ minikube service python-hello-world-external -n b
|-----------|-----------------------------|-------------|-----------------------------|
| NAMESPACE |            NAME             | TARGET PORT |             URL             |
|-----------|-----------------------------|-------------|-----------------------------|
| b         | python-hello-world-external | http        | http://192.168.39.196:31595 |
|-----------|-----------------------------|-------------|-----------------------------|

Flask API A:

from flask import Flask

app = Flask(__name__)

@app.route('/')
def index():
    return "Hello World A"

if __name__ == '__main__':
    app.run(debug=False, port=9090, host='0.0.0.0')

Flask API B:

import requests
from flask import Flask

app = Flask(__name__)

@app.route('/a')
def call_a():
    response = requests.get("I DONT KNOW WHAT TO PUT HERE")
    return response

if __name__ == '__main__':
    app.run(debug=False, port=9091, host='0.0.0.0') 

1. Is it possible to send the request internally using minikube?
2. If so, am I missing something in my configuration?
3. If so, what URL do I write in the requests.get("")?