springboot跨域请求解决方案+前后端分离跨域问题其他解决方案

如今的这个生态圈百花齐放，前后分离开始热门起来了，前端也要MVC了，那么你最常碰到的问题是什么？跨域请求会不会在你的问题名单中？

这里有有张摘自网络的图片

简述跨域问题

SpringBoot跨域请求

1、直接采用SpringBoot的注解@CrossOrigin

2、处理跨域请求的Configuration

CrossOriginConfig.java

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

/**
 * AJAX请求跨域
 * @author Mr.W
 * @time 2018-08-13
 */
@Configuration
public class CorsConfig extends WebMvcConfigurerAdapter {
    static final String ORIGINS[] = new String[] { "GET", "POST", "PUT", "DELETE" };
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**").allowedOrigins("*").allowCredentials(true).allowedMethods(ORIGINS)
                .maxAge(3600);
    }
}

3、采用HTTP请求的接口

@RestController
public class HelloController {
    
    @Autowired
    HelloService helloService;
    
    @GetMapping(value = "/test", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
    public String query() {
        return "hello";
    }
}

4、（稳定操作）采用过滤器的方式

 private CorsConfiguration buildConfig() {
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedMethod("*");
        corsConfiguration.addExposedHeader(HttpHeaderConStant.X_TOTAL_COUNT);
        return corsConfiguration;
    }

    /**
     * 跨域过滤器
     *
     * @return
     */
    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", buildConfig()); 
        return new CorsFilter(source);
    }

还有些千奇百怪的写法，但是作用都是一个：

//统一过滤器设置
public class DomainFilter  implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @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-Methods", "POST, GET, OPTIONS, DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.addHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
        chain.doFilter(req, res);
    }

    @Override
    public void destroy() {

    }
}


//spring boot过滤器设置
    @Bean
    public FilterRegistrationBean filterRegistrationBean() {
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        DomainFilter domainFilter = new DomainFilter();
        registrationBean.setFilter(domainFilter);
        List<String> urlPatterns = new ArrayList<String>();
        urlPatterns.add("/*");
        registrationBean.setUrlPatterns(urlPatterns);
        return registrationBean;
    }

前后分离的跨域问题其他解决方案

Nginx服务器反向代理

通过反向代理服务器监听同端口，同域名的访问，不同路径映射到不同的地址，比如，在nginx服务器中，监听同一个域名和端口，不同路径转发到客户端和服务器，把不同端口和域名的限制通过反向代理，来解决跨域的问题。

server {
        listen       80;
        server_name  abc.com;
        #charset koi8-r;
        #access_log  logs/host.access.log  main;

        location /client { #访问客户端路径
            proxy_pass http://localhost:81;
            proxy_redirect default;
        }
        location /apis { #访问服务器路径
            rewrite  ^/apis/(.*)$ /$1 break;
            proxy_pass   http://localhost:82;
       }
}