健康检查

2024年07月18日

柏拉文

越努力，越幸运

一、认识

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二、Dockerfile

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Dockerfile 可以通过 HEALTHCHECK 来检查 Docker 的运行状态

2.1 Node 健康检查

index.js

const http = require("http");
const PORT = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader("Content-Type", "text/plain");
  res.end(`Hello from Node.js`);
});

server.listen(PORT, () => {
  console.log(`Server running at port ${PORT}`);
});

Dockerfile

FROM node:latest
WORKDIR /app
COPY . /app 
EXPOSE 3000
HEALTHCHECK --interval=5s --timeout=3s --retries=3 CMD curl -f http://localhost:3000 || exit 1
CMD ["node","index.js"]

通过 docker inspect node 或者 docker ps 来查看健康状态

三、DockerCompose

---

Docker Compose 通过 healthcheck 来进行健康检查

3.1 Node 健康检查

index.js

const http = require("http");
const PORT = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader("Content-Type", "text/plain");
  res.end(`Hello from Node.js`);
});

server.listen(PORT, () => {
  console.log(`Server running at port ${PORT}`);
});

Dockerfile

FROM node:latest
WORKDIR /app
COPY . /app 
EXPOSE 3000
CMD ["node","index.js"]

docker-compose.yml

services:
  node1:
    build:
      context: .
      dockerfile: Dockerfile
    container_name: node1
    ports:
      - 3000:3000
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:3000"]
      interval: 30s
      timeout: 3s
      retries: 3
    networks:
      - node1
  node2:
    image: node:latest
    container_name: node2
    depends_on:
      node1:
        condition: service_healthy
    networks:
      - node1

networks:
  node1:
    driver: bridge