How to implement cross-origin resource sharing in Spring Boot?

There are multiple ways to implement Cross-Origin Resource Sharing (CORS) in Spring Boot, and one commonly used method is as follows:

1. Add cross-origin configuration in the configuration class of Spring Boot.

@Configuration
public class CorsConfig {

    @Bean
    public WebMvcConfigurer corsConfigurer() {
        return new WebMvcConfigurer() {
            @Override
            public void addCorsMappings(CorsRegistry registry) {
                registry.addMapping("/**")
                        .allowedOrigins("*") // 允许所有域名访问，也可以指定特定域名
                        .allowedMethods("GET", "POST", "PUT", "DELETE") // 允许的请求方法
                        .allowedHeaders("*") // 允许的请求头
                        .allowCredentials(true) // 是否允许发送 Cookie
                        .maxAge(3600); // 探测请求的有效期
            }
        };
    }
}

The above code will allow all domains to access and send cookies, and the configuration can be adjusted according to actual needs.

1. Use the @CrossOrigin annotation:

By adding the @CrossOrigin annotation to the method in the Controller layer, it is also possible to achieve cross-origin resource sharing, for example:

@RestController
public class MyController {

    @CrossOrigin(origins = "*", maxAge = 3600)
    @GetMapping("/hello")
    public String hello() {
        return "Hello, world!";
    }
}

These are two common methods used to implement Cross-Origin Resource Sharing. In practical projects, you can choose the most suitable method according to your needs.