spring,springmv,springboot解决跨域问题

 SpringMvc:

<mvc:cors>
        <mvc:mapping path="/**" allowed-origins="*" allow-credentials="true" max-age="1800"
        allowed-methods="GET,POST,PUT,DELETE,PATCH,OPTIONS"/>
    </mvc:cors>

 在发生全局异常和文件上传过大时,没有添加相应的头，所以不推荐

public class CorsInterceptor implements HandlerInterceptor {
 
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse response, Object o) throws Exception {
        System.out.println("添加跨域支持");
        //添加跨域CORS
        response.addHeader("Access-Control-Max-Age", "1800");//30 min
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Headers", "X-Requested-With,content-type,Content-Type,token");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, PATCH");
        return true;
    }
 
    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle");
    }
 
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("afterCompletion");
    }
}

 上面这种也可以，但是没有处理预检请求,考虑还是采用下面CorsFilter的方式

Spring:

public class OssCorsFilter extends OncePerRequestFilter{

    private CorsProcessor processor = new DefaultCorsProcessor();
    private CorsConfiguration corsConfiguration = new CorsConfiguration();

    //构造代码块初始化跨域配置
    {
        corsConfiguration.setAllowedOrigins(Arrays.asList("*"));
        corsConfiguration.setAllowCredentials(true);
        corsConfiguration.setAllowedHeaders(Arrays.asList("*"));
        corsConfiguration.setAllowedMethods(Arrays.asList("*"));
        corsConfiguration.setExposedHeaders(Arrays.asList("Original-Filename"));
        corsConfiguration.setMaxAge(3600l);
    }
    
    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
            throws ServletException, IOException {
        
        //此处的代码复制来源为Spring的CorsFilter
        if (CorsUtils.isCorsRequest(request)) {
            if (corsConfiguration != null) {
                boolean isValid = this.processor.processRequest(corsConfiguration, request, response);
                if (!isValid || CorsUtils.isPreFlightRequest(request)) {
                    return;
                }
            }
        }
        
        filterChain.doFilter(request, response);
    }
}

import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;

/**
 * 允许跨域
 */
public class MyCorsFilter extends CorsFilter  {

    public MyCorsFilter() {
        super(configurationSource());
    }

    private static UrlBasedCorsConfigurationSource configurationSource() {
        CorsConfiguration config = new CorsConfiguration();
        config.setAllowCredentials(true);
        config.addAllowedOrigin("http://localhost:8081");
        config.addAllowedHeader("*");
        config.addAllowedMethod("*");
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", config);
        return source;
    }
}

 SpringBoot:

@Configuration
public class GlobalCorsConfig {
    
    @Bean
    public CorsFilter corsFilter() {
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        corsConfiguration.setAllowCredentials(true);
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedMethod("*");
        UrlBasedCorsConfigurationSource urlBasedCorsConfigurationSource = new UrlBasedCorsConfigurationSource();
        urlBasedCorsConfigurationSource.registerCorsConfiguration("/**", corsConfiguration);
        return new CorsFilter(urlBasedCorsConfigurationSource);
    }

}

@Configuration
public class MvcConfig implements WebMvcConfigurer {
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                //.allowedHeaders("Origin", "X-Requested-With", "Content-Type", "Accept", "X-Token", "content-type")
                .allowedHeaders("*")  //服务器允许的请求头
                .allowedMethods("POST", "PUT", "GET", "OPTIONS", "DELETE")  //服务器允许的请求方法
                .allowCredentials(true)  //允许带 cookie 的跨域请求
                .allowedOrigins("*")  //服务端允许哪些域请求资源
                .maxAge(3600);   //预检请求的缓存时间
    } 
}

   @Bean
    public FilterRegistrationBean<CorsFilter> corsFilter() {
        FilterRegistrationBean<CorsFilter> corsFilterFilterRegistrationBean = new FilterRegistrationBean<>();
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.setAllowedMethods(Arrays.asList("POST", "PUT", "GET", "OPTIONS", "DELETE"));
        corsConfiguration.setAllowCredentials(true);
        corsConfiguration.setMaxAge(3600L);
        source.registerCorsConfiguration("/**", corsConfiguration);
        corsFilterFilterRegistrationBean.setFilter(new CorsFilter(source));
        corsFilterFilterRegistrationBean.setOrder(-1);
        return corsFilterFilterRegistrationBean;
    }

package com.lemon.springboot.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

/**
 * @author lemon
 */
@RestController
@RequestMapping("/api")
public class ApiController {

    private static final Logger logger = LoggerFactory.getLogger(ApiController.class);

    @CrossOrigin({"http://localhost:8081", "http://localhost:8082"})
    @RequestMapping("/get")
    public Map<String, Object> get(@RequestParam String name) {
        Map<String, Object> map = new HashMap<>();
        map.put("title", "hello world");
        map.put("name", name);
        return map;
    }
}