吊炸天，Spring Security还有这种用法！

在用Spring Security项目开发中，有时候需要放通某一个接口时，我们需要在配置中把接口地址配置上，这样做有时候显得麻烦，而且不够优雅。我们能不能通过一个注解的方式，在需要放通的接口上加上该注解，这样接口就能放通了。答案肯定是可以的啦，今天我们一起来看看实现过程吧。

SpringBoot版本

本文基于的Spring Boot的版本是2.6.7

实现思路

• 新建一个AnonymousAccess注解，该注解是应用于Controller方法上的
• 新建一个存放所有请求方式的枚举类
• 通过判断Controller方法上是否存在该注解
• 在SecurityConfig上进行策略的配置

实现过程

新建注解

@Inherited
@Documented
@Target({ElementType.METHOD,ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface AnonymousAccess {
    
}

新建请求枚举类

该类是存放所有的请求类型的，代码如下：

@Getter
@AllArgsConstructor
public enum RequestMethodEnum {
    /**
     * 搜寻 @AnonymousGetMapping
     */
    GET("GET"),

    /**
     * 搜寻 @AnonymousPostMapping
     */
    POST("POST"),

    /**
     * 搜寻 @AnonymousPutMapping
     */
    PUT("PUT"),

    /**
     * 搜寻 @AnonymousPatchMapping
     */
    PATCH("PATCH"),

    /**
     * 搜寻 @AnonymousDeleteMapping
     */
    DELETE("DELETE"),

    /**
     * 否则就是所有 Request 接口都放行
     */
    ALL("All");

    /**
     * Request 类型
     */
    private final String type;

    public static RequestMethodEnum find(String type) {
        for (RequestMethodEnum value : RequestMethodEnum.values()) {
            if (value.getType().equals(type)) {
                return value;
            }
        }
        return ALL;
    }
}

判断Controller方法上是否存在该注解

在SecurityConfig类中定义一个私有方法getAnonymousUrl，该方法主要作用是判断controller那些方法加上了AnonymousAccess的注解

    private Map<String, Set<String>> getAnonymousUrl(Map<RequestMappingInfo, HandlerMethod> handlerMethodMap) {
        Map<String, Set<String>> anonymousUrls = new HashMap<>(8);
        Set<String> get = new HashSet<>();
        Set<String> post = new HashSet<>();
        Set<String> put = new HashSet<>();
        Set<String> patch = new HashSet<>();
        Set<String> delete = new HashSet<>();
        Set<String> all = new HashSet<>();
        for (Map.Entry<RequestMappingInfo, HandlerMethod> infoEntry : handlerMethodMap.entrySet()) {

            HandlerMethod handlerMethod = infoEntry.getValue();
            AnonymousAccess anonymousAccess = handlerMethod.getMethodAnnotation(AnonymousAccess.class);
            if (null != anonymousAccess) {
                List<RequestMethod> requestMethods = new ArrayList<>(infoEntry.getKey().getMethodsCondition().getMethods());
                RequestMethodEnum request = RequestMethodEnum.find(requestMethods.size() == 0 ? RequestMethodEnum.ALL.getType() : requestMethods.get(0).name());
                switch (Objects.requireNonNull(request)) {
                    case GET:
                        get.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                    case POST:
                        post.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                    case PUT:
                        put.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                    case PATCH:
                        patch.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                    case DELETE:
                        delete.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                    default:
                        all.addAll(infoEntry.getKey().getPatternsCondition().getPatterns());
                        break;
                }
            }
        }
        anonymousUrls.put(RequestMethodEnum.GET.getType(), get);
        anonymousUrls.put(RequestMethodEnum.POST.getType(), post);
        anonymousUrls.put(RequestMethodEnum.PUT.getType(), put);
        anonymousUrls.put(RequestMethodEnum.PATCH.getType(), patch);
        anonymousUrls.put(RequestMethodEnum.DELETE.getType(), delete);
        anonymousUrls.put(RequestMethodEnum.ALL.getType(), all);
        return anonymousUrls;
    }

在SecurityConfig上进行策略的配置

通过一个SpringUtil工具类获取到requestMappingHandlerMapping的Bean,然后通过getAnonymousUrl方法把标注AnonymousAccess接口找出来。最后，通过antMatchers细腻化到每个 Request 类型。

    @Override
    protected void configure(HttpSecurity httpSecurity) throws Exception {
        // 搜寻匿名标记 url： @AnonymousAccess
        RequestMappingHandlerMapping requestMappingHandlerMapping = (RequestMappingHandlerMapping) SpringUtil.getBean("requestMappingHandlerMapping");
        Map<RequestMappingInfo, HandlerMethod> handlerMethodMap = requestMappingHandlerMapping.getHandlerMethods();
        // 获取匿名标记
        Map<String, Set<String>> anonymousUrls = getAnonymousUrl(handlerMethodMap);
        httpSecurity
                //禁用CSRF
                .csrf().disable()
                .authorizeRequests()
                // 自定义匿名访问所有url放行：细腻化到每个 Request 类型
                // GET
                .antMatchers(HttpMethod.GET,anonymousUrls.get(RequestMethodEnum.GET.getType()).toArray(new String[0])).permitAll()
                // POST
                .antMatchers(HttpMethod.POST,anonymousUrls.get(RequestMethodEnum.POST.getType()).toArray(new String[0])).permitAll()
                // PUT
                .antMatchers(HttpMethod.PUT,anonymousUrls.get(RequestMethodEnum.PUT.getType()).toArray(new String[0])).permitAll()
                // PATCH
                .antMatchers(HttpMethod.PATCH,anonymousUrls.get(RequestMethodEnum.PATCH.getType()).toArray(new String[0])).permitAll()
                // DELETE
                .antMatchers(HttpMethod.DELETE,anonymousUrls.get(RequestMethodEnum.DELETE.getType()).toArray(new String[0])).permitAll()
                // 所有类型的接口都放行
                .antMatchers(anonymousUrls.get(RequestMethodEnum.ALL.getType()).toArray(new String[0])).permitAll()
                // 所有请求都需要认证
                .anyRequest().authenticated();
        
    }

在Controller方法上应用

在Controller上把需要的放通的接口上加上注解，即可不需要认证就可以访问了，是不是很方便呢。例如，验证码不需要认证访问的，代码如下：

    @ApiOperation(value = "获取验证码", notes = "获取验证码")
    @AnonymousAccess
    @GetMapping("/code")
    public Object getCode(){

        Captcha captcha = loginProperties.getCaptcha();
        String uuid = "code-key-"+IdUtil.simpleUUID();
        //当验证码类型为 arithmetic时且长度 >= 2 时，captcha.text()的结果有几率为浮点型
        String captchaValue = captcha.text();
        if(captcha.getCharType()-1 == LoginCodeEnum.ARITHMETIC.ordinal() && captchaValue.contains(".")){
            captchaValue = captchaValue.split("\\.")[0];
        }
        // 保存
        redisUtils.set(uuid,captchaValue,loginProperties.getLoginCode().getExpiration(), TimeUnit.MINUTES);
        // 验证码信息
        Map<String,Object> imgResult = new HashMap<String,Object>(2){{
            put("img",captcha.toBase64());
            put("uuid",uuid);
        }};
        return imgResult;

    }

效果展示

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