Microservices on Kubernetes with Docker Desktop

Scenario: Publish 4 microservices on Kubernetes with Docker Desktop

Tech stack: .NET Core, Visual Studio, Kubernetes on Docker Desktop (on Windows)

GitHub: Ecommerce — Kubernetes Run

(1) Docker desktop includes standalone Kubernetes server and client.

(2) Services and data flow example are similar to explanation in Microservices on Docker Desktop.

• CustomerService
• OrderService
• ProductService
• SearchService

(3) Kubernetes YAML files

• searchservice-deploy.yml

## Includes endpoints for customerservice, orderservice and productservice
## searchservice docker image is loaded from Local registry
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: searchservice
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: searchservice
    spec:
      containers:
      - name: searchservice
        image: localhost:5000/searchservice:latest
        imagePullPolicy: Always
        ports:
        - containerPort: 30003
        env:
        - name: ASPNETCORE_URLS
          value: http://*:30003
        - name: CustomersUrl
          value: http://customerservice
        - name: ProductsUrl
          value: http://productservice
        - name: OrdersUrl
          value: http://orderservice
  selector:
    matchLabels:
      app: searchservice
---
apiVersion: v1
kind: Service
metadata:
  name: searchservice
spec:
  type: LoadBalancer
  ports:
  - port: 30003
  selector:
    app: searchservice

• customerservice-deploy.yml

## customerservice docker image is loaded from Local registry

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: customerservice #default dns name
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: customerservice
    spec:
      containers:
      - name: customerservice
        image: localhost:5000/customerservice:latest
        imagePullPolicy: Always
        ports:
        - containerPort: 80
        env:
        - name: ASPNETCORE_URLS
          value: http://*:80
  selector:
    matchLabels:
      app: customerservice
---
apiVersion: v1
kind: Service
metadata:
  name: customerservice
spec:
  ports:
  - port: 80
  type: LoadBalancer
  selector:
    app: customerservice

• orderservice-deploy.yml

## orderservice docker image is loaded from Local registry

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: orderservice #default dns name
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: orderservice
    spec:
      containers:
      - name: orderservice
        image: localhost:5000/orderservice:latest
        imagePullPolicy: Always
        ports:
        - containerPort: 80
        env:
        - name: ASPNETCORE_URLS
          value: http://*:80
  selector:
    matchLabels:
      app: orderservice
---
apiVersion: v1
kind: Service
metadata:
  name: orderservice
spec:  
  ports:
  - port: 80
  type: ClusterIP
  selector:
    app: orderservice

• productservice-deploy.yml

## productservice docker image is loaded from Local registry

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: productservice #default dns name
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: productservice
    spec:
      containers:
      - name: productservice
        image: localhost:5000/productservice:latest
        imagePullPolicy: Always
        ports:
        - containerPort: 80
        env:
        - name: ASPNETCORE_URLS
          value: http://*:80
  selector:
    matchLabels:
      app: productservice
---
apiVersion: v1
kind: Service
metadata:
  name: productservice
spec:  
  ports:
  - port: 80
  type: ClusterIP
  selector:

(3) Local registry setup

• Creating local registry in Docker Desktop provides a store for docker images.
• Kubernetes YAML files are setup to load docker images from the local registry.

## create registry

docker run -d -p 5000:5000 --restart=always --name registry registry:2


## build and push docker images to registry

docker build -t productservice .
docker tag productservice localhost:5000/productservice
docker push localhost:5000/productservice

docker build -t customerservice .
docker tag customerservice localhost:5000/customerservice
docker push localhost:5000/customerservice

docker build -t orderservice .
docker tag orderservice localhost:5000/orderservice
docker push localhost:5000/orderservice

docker build -t searchservice .
docker tag searchservice localhost:5000/searchservice
docker push localhost:5000/searchservice

(4) Deploy services to Kubernetes on Docker Desktop (after registry is setup)

kubectl apply -f customerservice-deploy.yml

kubectl apply -f productservice-deploy.yml

kubectl apply -f orderservice-deploy.yml

kubectl apply -f searchservice-deploy.yml

(5) Call SearchService

Post HTTP: http://localhost/api/search

Body:
{
 "customerId": 1
}