需求

利用 docker compose 快速搭建一個可以統(tǒng)計訪問次數(shù)的 java web服務(wù).

環(huán)境準備

安裝 docker.

• docker
• docker desktop (window | mac)

步驟

1 新建 java web 服務(wù)

spring boot 2.x

<parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>2.6.11</version>
  <relativePath/> <!-- lookup parent from repository -->
</parent>

<properties>
    <java.version>8</java.version>
</properties>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-redis</artifactId>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

編寫 Controller .

@RestController
public class AccessCounterController {
    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    @GetMapping("/hello")
    public String hello() {
        Long counter = stringRedisTemplate.opsForValue().increment("accCounter");
        return "頁面訪問的次數(shù): " + counter;
    }

}

項目配置

server.port=8080
spring.redis.host=redis
spring.redis.port=6379

2 Dockerfile 和 docker-compose.yml

FROM java:8
COPY target/*.jar /app/acc-counter/app.jar
CMD ["--server.port=8080"]

WORKDIR /app/acc-counter
EXPOSE 8080
ENTRYPOINT ["java", "-jar", "app.jar"]
version: "3.9"
services:
  acc-counter-app:
    build: .
    image: acc-counter-app
    depends_on:
      - redis
    ports:
      - "8080:8080"
  redis:
    image: "library/redis:alpine"

3 打包工程

mvn package

4 up

docker-compose up -d

第一次會自動先 build.

訪問一下

坑

1. 如果后續(xù)需要修改 Dockerfile 配置, 修改后, 要先顯示 docker-compose build, 否則, 即使你使用 up 指令新的修改不生效, 因為它會識別到之前build的過, 不會重新build.
2. 注意環(huán)境版本, 我這里使用 java8+springboot 2.x+maven 3.x