写一个简单食用的拦截器

写个Filter继承OncePerRequestFilter重写doFilterInternal

1、doFilterInternal方法

@WebFilter(filterName = "tenantAuthCheckFilter", urlPatterns = {"/v1/url/*"})
@Order(1)
public class TenantFilter extends OncePerRequestFilter {

    @Autowired
    private ServiceA serviceA;

    @Autowired
    private ExcludePathsConfig excludePathsConfig;

    @Override
    protected void doFilterInternal(@NotNull HttpServletRequest request, @NotNull HttpServletResponse response, @NotNull FilterChain filterChain) throws ServletException, IOException {
        String servletPath = request.getServletPath();
        String userId = request.getHeader("userId");
        if (!excludePathsConfig.getPaths().contains(servletPath)) {
            User user = ServiceA.getProdInst(prodInstId);
            if(user.getUserId!=userId){
                throw new Exception("当前用户没权限");
            }
        }
        filterChain.doFilter(request, response);
    }
}

2、 将applicaiton.yml下的配置读取成List<String>

@Component
@ConfigurationProperties(prefix = "interceptorconfig.exclude")
@Data
public class ExcludePathsConfig {
    private List<String> paths;
}

3、application.yml配置 

interceptorconfig: # 拦截器配置
  exclude:
    paths:
      - /v1/url/userList # 不拦截这个接口
      - /v1/url/dict # 不拦截这个接口

4、启动类增加ServletComponentScan（）

@ServletComponentScan(basePackages = {"cn.lihaiyu.test.*"})

5、Filter抛出错误方案

@RestController
public class ErrorController extends BasicErrorController {

    public ErrorController() {
        super(new DefaultErrorAttributes(), new ErrorProperties());
    }

    @RequestMapping(produces = {MediaType.APPLICATION_JSON_VALUE})
    @Override
    public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
        Map<String, Object> errorAttributes = getErrorAttributes(request, ErrorAttributeOptions.of(ErrorAttributeOptions.Include.EXCEPTION,ErrorAttributeOptions.Include.MESSAGE,ErrorAttributeOptions.Include.STACK_TRACE,ErrorAttributeOptions.Include.BINDING_ERRORS));
        HttpStatus status = getStatus(request);
        // 错误代码：-1
        String code = String.valueOf(ErrorType.SYS_ERROR.getCode());
        // 获取错误信息
        String message = errorAttributes.get("message").toString();

        ApiErrorResult apiErrorResult = new ApiErrorResult(code,message);
        return new ResponseEntity<>(apiErrorResult,status);
    }
}

public class ApiErrorResult extends LinkedHashMap<String,Object> {

    private static final String CODE_KEY = "code";
    private static final String MESSAGE_KEY =  "message";

    public ApiErrorResult(String code, String message) {
        this.put(CODE_KEY,code);
        this.put(MESSAGE_KEY,message);
    }
}

6、需要注意的地方：

① 使用ServletComponentScan

SpringBootApplication 上使用@ServletComponentScan 注解后
Servlet可以直接通过@WebServlet注解自动注册
Filter可以直接通过@WebFilter注解自动注册
Listener可以直接通过@WebListener 注解自动注册

原文链接：https://blog.csdn.net/qq_35574640/article/details/87936672

② 不要在Filter上面使用@Component，否则 urlPatterns 失效，会拦截所有的请求

③ 抛出错误的方法，filter内无法直接抛出错误，需要借助 BasicErrorController