SpringBoot自定義攔截器

攔截器常用的場景

權限驗證，判斷用戶是否登錄，防重複提交等等

自定義攔截器

1. 實現HandlerInterceptor接口

HandlerInterceptor接口

public interface HandlerInterceptor {
	//在業務處理器處理請求之前被調用;預處理，可以進行編碼、安全控制、權限校驗等處理
	default boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {

		return true;
	}
	//在業務處理器處理請求執行完成後，生成視圖之前執行。
	default void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			@Nullable ModelAndView modelAndView) throws Exception {
	}
	//在DispatcherServlet完全處理完請求後被調用
	default void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
			@Nullable Exception ex) throws Exception {
	}

}

實現類
在本篇文章的用法，是對token校驗

public class JwtInterceptor implements HandlerInterceptor {
    
    @Autowired
    private JwtUtil jwtUtil;
    
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String header = request.getHeader("Authorization");
        if (StringUtils.isNotEmpty(header)){
            if (header.startsWith("Bearer ")){
                // 得到token
                final String token = header.substring(7);
                // 對令牌進行驗證
                try {
                    Claims claims = jwtUtil.parseJWT(token);
                    String roles = (String) claims.get("roles");
                    if ("admin".equals(roles)) {
                        request.setAttribute("claims_admin", token);
                    }
                    if ("user".equals(roles)) {
                        request.setAttribute("claims_user", token);
                    }
                } catch (Exception e) {
                    throw new RuntimeException("令牌有誤!");
                }
            }
        }
        return true;
    }
}

2. 繼承WebMvcConfigurationSupport

WebMvcConfigurationSupport

@Configuration
public class InterceptorConfig extends WebMvcConfigurationSupport {

    @Autowired
    private JwtInterceptor jwtInterceptor;
	// 添加攔截器
    @Override
    protected void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(jwtInterceptor)
                .addPathPatterns("/**")
                .excludePathPatterns("/**/login/**");

    }
}