基于SpringBoot+Docker实现可挂载可热更新的config.json

# Spring Boot 2.4+ 使用这个
spring.web.resources.static-locations=file:/app/static/, classpath:/static/

# Spring Boot 2.3- 使用这个
spring.resources.static-locations=file:/app/static/, classpath:/static/

前端请求 /config.json 或 /wvp/config.json
→ 后端 Controller 先尝试读取 容器内 /app/config/config.json
→ 如果存在直接返回
→ 如果不存在再 fallback 到 classpath:/static/config.json

@RestController
public class WvpIndexController {

    private static final String EXTERNAL_PATH = "/app/config/config.json";
    private static final String CLASSPATH_PATH = "classpath:/static/config.json";

    @GetMapping({"/config.json", "/wvp/config.json"})
    public ResponseEntity<Resource> getConfig(HttpServletResponse response) {

        Resource resource;

        // 1) 优先尝试读取外部挂载文件
        File external = new File(EXTERNAL_PATH);
        if (external.exists() && external.isFile()) {
            resource = new FileSystemResource(external);
        } else {
            // 2) 不存在则 fallback 到内置 classpath
            resource = new ClassPathResource("static/config.json");
        }

        // 设置不缓存
        response.setHeader("Cache-Control", "no-store");

        return ResponseEntity.ok()
                .contentType(MediaType.APPLICATION_JSON)
                .body(resource);
    }
}

FROM openjdk:17-jdk-alpine

WORKDIR /app

COPY wvp.jar /app/wvp.jar
COPY static /app/static  # 静态资源 fallback

EXPOSE 8080

ENTRYPOINT ["java", \
  "-Dspring.web.resources.static-locations=file:/app/static/,classpath:/static/", \
  "-Dspring.resources.static-locations=file:/app/static/,classpath:/static/", \
  "-jar", "wvp.jar"]

docker-compose up -d