springboot跨域配置

悠悠 2022-04-25 08:04 223阅读 0赞

**跨域并非浏览器限制了发起跨站请求，而是跨站请求可以正常发起，但是返回结果被浏览器拦截了。最好的例子是CSRF跨站攻击原理，请求是发送到了后端服务器无论是否跨域！注意：有些浏览器不允许从HTTPS的域跨域访问HTTP，比如Chrome和Firefox，这些浏览器在请求还未发出的时候就会拦截请求，这是一个特例。**

引自：  
[https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Access\_control\_CORS][https_developer.mozilla.org_zh-CN_docs_Web_HTTP_Access_control_CORS]

**方法一：新增一个configration类 或 在Application中加入CorsFilter和CorsConfiguration方法**

import org.springframework.context.annotation.Bean;  
    import org.springframework.context.annotation.Configuration;  
    import org.springframework.web.cors.CorsConfiguration;  
    import org.springframework.web.cors.UrlBasedCorsConfigurationSource;  
    import org.springframework.web.filter.CorsFilter;  
      
    @Configuration  
    public class CorsConfig {  
        private CorsConfiguration buildConfig() {  
            CorsConfiguration corsConfiguration = new CorsConfiguration();  
            corsConfiguration.addAllowedOrigin("*"); // 1允许任何域名使用
            corsConfiguration.addAllowedHeader("*"); // 2允许任何头
            corsConfiguration.addAllowedMethod("*"); // 3允许任何方法（post、get等） 
            return corsConfiguration;  
        }  
      
        @Bean  
        public CorsFilter corsFilter() {  
            UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();  
            source.registerCorsConfiguration("/**", buildConfig()); // 4  
            return new CorsFilter(source);  
        }  
    }

**方法二：使用Filter方式**

import javax.servlet.*;  
    import javax.servlet.http.HttpServletResponse;  
    import java.io.IOException;  
       
    @Component  
    public class CorsFilter implements Filter {  
      
        final static org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(CorsFilter.class);  
     
        public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {  
            HttpServletResponse response = (HttpServletResponse) res;  
            response.setHeader("Access-Control-Allow-Origin", "*");  
            response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");  
            response.setHeader("Access-Control-Max-Age", "3600");  
            response.setHeader("Access-Control-Allow-Headers", "x-requested-with");  
            System.out.println("*********************************过滤器被使用**************************");  
            chain.doFilter(req, res);  
        }  
        public void init(FilterConfig filterConfig) {}  
        public void destroy() {}  
    }

[https_developer.mozilla.org_zh-CN_docs_Web_HTTP_Access_control_CORS]: https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Access_control_CORS