springBoot跨域问题

springBoot跨域问题

主要发生在不同的域名之间，进行相互请求，比如在http://localhost:8080中使用axios去请求http://localhost:8081.这就属于跨域请求（简单来说，需要请求的地址与发送请求的地址，域名不同）

方法1：全局配置

定义配置类，添加@Configuration注解，实现WebMvcConfigurer接口，再重写addCorsMappings方法：

// 请求跨域
@Configuration
public class CorsConfig implements WebMvcConfigurer {
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        //添加映射路径
        registry.addMapping("/**")
                //是否发送Cookie
                .allowCredentials(true)
                //设置放行哪些原始域   SpringBoot2.4.4下低版本使用.allowedOrigins("*")    
                .allowedOriginPatterns("*")
                //放行哪些请求方式
                .allowedMethods(new String[]{"GET", "POST", "PUT", "DELETE"})
                //.allowedMethods("*") //或者放行全部
                //放行哪些原始请求头部信息
                .allowedHeaders("*")
                //暴露哪些原始请求头部信息
                .exposedHeaders("*");
    }
}

方法2：局部跨域

Controller层在需要跨域的类或者方法上加上@CrossOrigin该注解即可。

@CrossOrigin(origins = "*",maxAge = 3600)
public class UserController {
 final UserService userService;
 
 @GetMapping("/getOne/{id}")
 public User getOne(@PathVariable("id") Integer id) {
  return userService.getById(id);
 }
我们也可以设置更小的粒度，在方法上设置跨域：

@Controller
@RequestMapping("/shop")
public class ShopController {

    @GetMapping("/")
    @ResponseBody
    //更小的解决跨域 设置只能某些地址访问
    @CrossOrigin(originPatterns = "http://localhost:8080")
    public Map<String, Object> findAll() {
        //返回数据
        return DataSchool.getStudents();
    }
}

方法3：定义跨域过滤器

1）编写过滤器

// 跨域过滤器
@Component
public class CORSFilter implements Filter {
 
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
  //*号表示对所有请求都允许跨域访问
        HttpServletResponse res = (HttpServletResponse) response;
        res.addHeader("Access-Control-Allow-Credentials", "true");
        res.addHeader("Access-Control-Allow-Origin", "*");
        res.addHeader("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT");
        res.addHeader("Access-Control-Allow-Headers", "Content-Type,X-CAF-Authorization-Token,sessionToken,X-TOKEN");
        if (((HttpServletRequest) request).getMethod().equals("OPTIONS")) {
            response.getWriter().println("Success");
            return;
        }
        chain.doFilter(request, response);
    }
 
    @Override
    public void destroy() {
 
    }
 
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
 
    }
}

2）注册过滤器

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