Spring Boot CORS 过滤器 - CORS 预检通道未成功

使用Spring Boot开发Web应用程序时，可能会遇到跨域资源共享（CORS）问题。CORS是一种浏览器安全机制，用于限制跨域请求。为了解决这个问题，我们可以使用Spring Boot提供的CORS过滤器。然而，在某些情况下，CORS预检通道可能会失败，导致跨域请求被阻止。本文将介绍如何使用Spring Boot CORS过滤器，并解决CORS预检通道失败的问题。

spring.mvc.dispatch-options-request=true
spring.webmvc.cors.allowed-origins=*
spring.webmvc.cors.allowed-methods=GET,POST,PUT,DELETE
spring.webmvc.cors.allowed-headers=*
spring.webmvc.cors.max-age=3600

java
@Component
public class CorsFilter implements Filter {
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        if (httpRequest.getMethod().equals("OPTIONS")) {
            httpResponse.setHeader("Access-Control-Allow-Origin", "*");
            httpResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,PUT,DELETE");
            httpResponse.setHeader("Access-Control-Allow-Headers", "*");
            httpResponse.setHeader("Access-Control-Max-Age", "3600");
            httpResponse.setStatus(HttpServletResponse.SC_OK);
        } else {
            chain.doFilter(request, response);
        }
    }
}

java
@SpringBootApplication
@EnableWebMvc
public class Application extends SpringBootServletInitializer {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }
    @Bean
    public FilterRegistrationBean corsFilter() {
        FilterRegistrationBean registrationBean = new FilterRegistrationBean<>();
        registrationBean.setFilter(new CorsFilter());
        registrationBean.addUrlPatterns("/*");
        return registrationBean;
    }
}