SpringBoot–跨域的解决方案

简介

本文介绍SpringBoot如何处理跨域问题。

方案1：过滤器（推荐）

在response中写入跨域响应头。

写法1：

package com.xxx.common.config;

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;

/**
 * 跨域配置
 */
@Configuration
public class CorsConfig {
    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource urlBasedCorsConfigurationSource = new UrlBasedCorsConfigurationSource();
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        /*是否允许请求带有验证信息*/
        corsConfiguration.setAllowCredentials(true);
        /*允许访问的客户端域名*/
        corsConfiguration.addAllowedOrigin("*");
        /*允许服务端访问的客户端请求头*/
        corsConfiguration.addAllowedHeader("*");
        /*允许访问的方法名：GET POST等*/
        corsConfiguration.addAllowedMethod("*");
        urlBasedCorsConfigurationSource.registerCorsConfiguration("/**", corsConfiguration);
        return new CorsFilter(urlBasedCorsConfigurationSource);
    }
}

写法2：

import org.springframework.context.annotation.Configuration;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 跨域配置
 */
@Component
public class CorsFilter implements Filter {
    @Override
    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-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, PATCH, DELETE, PUT");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
        chain.doFilter(req, res);
    }
}

方案2：实现WebMvcConfigurer接口（不推荐）

此法在不同的SpringBoot版本中有不同的问题，不推荐。

package com.example.demo.common.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * 跨域配置
 */
@Configuration
public class CorsConfig implements WebMvcConfigurer {
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                // .allowedOrigins("*") // SpringBoot2.4.0之前的版本
                .allowedOriginPatterns("*") // SpringBoot2.4.0及之后的版本
                .allowedMethods("GET", "HEAD", "POST", "PUT", "DELETE", "OPTIONS")
                .allowCredentials(true)
                .maxAge(3600)
                .allowedHeaders("*");
    }
}

方案3：采用注解@CrossOrigin

对于某个方法或类，可以用这个注解。

@RestController
@CrossOrigin
@RequestMapping("/situation")
public class TestController {
 
}