快速安装Kubernetes集群与Django应用示例

├── build.sh
├── Dockerfile
├── requirements.txt
└── src
    ├── src为django项目根目录

FROM python:3.6

# 如果在中国，apt 使用镜像
RUN curl -s ifconfig.co/json | grep "China" > /dev/null && \
    curl -s http://mirrors.163.com/.help/sources.list.jessie > /etc/apt/sources.list || true

# 安装开发所需要的一些工具，同时方便在服务器上进行调试
RUN apt-get update;\
    apt-get install -y vim gettext postgresql-client;\
    true

COPY . /opt/demo
WORKDIR /opt/demo/src

# 先判断是否在中国，如果在中国，使用镜像下载
RUN curl -s ifconfig.co/json | grep "China" > /dev/null && \
    pip install -r /opt/demo/requirements.txt -i https://pypi.doubanio.com/simple --trusted-host pypi.doubanio.com || \
    pip install -r /opt/demo/requirements.txt

RUN mkdir /opt/logging
RUN mkdir /opt/running

docker build -t 127.0.0.1:5000/backend:v1.0 . && docker push 127.0.0.1:5000/backend:v1.0

# backend
# dns: backend-service.demo.svc.cluster.local
---
apiVersion: v1
kind: Service
metadata:
  name: backend-service
  namespace: demo
spec:
  ports:
  - port: 80
    targetPort: 8000
  selector:
    app: backend-pod

# ingress 负载均衡
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: backend-ingress
  namespace: demo
spec:
  rules:
      paths:
        - path: /
          backend:
            serviceName: backend-service
            servicePort: 80

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: demo-backend
  namespace: demo
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: backend-pod
    spec:
      containers:
        - name: demo-backend
          image: 140.xx.xx.181:5000/backend:v1.0   # 你的后端打包的镜像地址（私有）
          imagePullPolicy: Always

          ports:
            - containerPort: 8000
          command: ["/bin/sh"]
          args: ["-c", "python manage.py runserver 0.0.0.0:8000"]
          # python manage.py runserver 0.0.0.0:8000 为测试使用，应使用uwsgi等方式

      initContainers:
        - name: wait-redis
          image: busybox
          command: ['sh', '-c', 'until nslookup redis.demo.svc.cluster.local; do echo waiting for redis service; sleep 2; done;']
        - name: wait-postgresql
          image: busybox
          command: ['sh', '-c', 'until nslookup postgresql.demo.svc.cluster.local; do echo waiting for postgresql service; sleep 2; done;']

---
apiVersion: batch/v1
kind: Job
metadata:
  name: sync-db
spec:
  template:
    metadata:
      name: sync-db
      labels:
        app: backend-sync-db-job
    spec:
      containers:
      - name: backend-db-migrate
        image: 140.xx.xx.181:5000/backend:v1.0
        command:
        - "/bin/sh"
        - "-c"
        - "python manage.py makemigrations && python manage.py migrate"
      restartPolicy: Never

# postgresql
# dns: postgresql.demo.svc.cluster.local
---
apiVersion: v1
kind: Service
metadata:
  name: postgresql
  namespace: demo
spec:
  ports:
    - port: 5432
      targetPort: postgresql-port
  selector:
    app: postgresql-pod

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: demo-postgresql
  namespace: demo
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: postgresql-pod
    spec:
      nodeName: 140.xx.xx.164   # 为了数据的持久化指定调度节点为node1: 140.xx.xx.164 
      containers:
        - name: demo-postgresql
          image: postgres:9.6.3
          imagePullPolicy: Always

          env:
            - name: POSTGRES_DB
              value: demo
            - name: POSTGRES_USER
              value: root
            - name: POSTGRES_PASSWORD
              value: devpwd

          ports:
            - name: postgresql-port
              containerPort: 5432

          volumeMounts:
            - name: postgresql-storage
              mountPath: /var/lib/postgresql

      volumes:
        - name: postgresql-storage
          hostPath:
            path: /data/postgresql   # 为了数据的持久化，使用主机hostPath方式挂载数据卷

# redis
# dns: redis.demo.svc.cluster.local
---
apiVersion: v1
kind: Service
metadata:
  name: redis
  namespace: demo
spec:
  ports:
    - port: 9200
      targetPort: redis-port
  selector:
    app: redis-pod

---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: demo-redis
  namespace: demo
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: redis-pod
    spec:
      containers:
        - name: demo-redis
          image: redis:3.0.7
          imagePullPolicy: Always

          ports:
            - name: redis-port
              containerPort: 6379

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'demo',
        'USER': 'root',
        'PASSWORD': 'devpwd',
        'HOST': 'postgresql.demo.svc.cluster.local',
        'PORT': '',
    }
}

REDIS_HOST = "redis.demo.svc.cluster.local"
# 对于不解析dns的应用配置，可以在配置文件中手动解析,如
# import socket 
# REDIS_HOST = socket.gethostbyname("redis.demo.svc.cluster.local")

kubectl create namespace demo  # create namespace

kubectl -n demo apply -f .  # apply backend.yaml postgres.yaml yaml

kubectl -n demo get pods