获取错误：“Access Control Allow Origin”标头包含多个值“*，*”，但只允许一个值

Question

我试图在Java/Spring中的Angular前端和RESTendpoint之间建立连接（我没有开发，也不太清楚）。通过GET，一切正常。通过POST，我在终端中收到消息

已被CORS策略阻止：对预检请求的响应未通过权限改造检查：请求的资源上不存在“访问控制允许源”标头。

在开发工具的网络选项卡中，OPTIONS方法出现错误403

Request Method: OPTIONS
Status Code: 403 
Remote Address: xx.xx.xx.xx:xxxx
Referrer Policy: strict-origin-when-cross-origin

所以，我在互联网上搜索了几次后发现了这种情况，原因是CORS设置：通常，在这种情况下，在帖子之前会发送一个选项调用；但是，由于CORS的原因，不允许进行期权认购。所以，我试着在我的控制器上设置这一行

@CrossOrigin(origins = "*", methods = {RequestMethod.OPTIONS, RequestMethod.GET, RequestMethod.POST, RequestMethod.PUT, RequestMethod.DELETE})

这次错误改变了

Multiple CORS header 'Access-Control-Allow-Origin' not allowed
But the code I added is the only similar to @CrossOrigin, I dind't found others similar.

因此，在根据后CORS问题-没有'访问控制允许源'头存在于请求的资源，我尝试了以下解决方案：

@Configuration
public class WebConfig extends WebMvcConfigurerAdapter {

    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedMethods("HEAD", "GET", "PUT", "POST", "DELETE", "PATCH");
    }
}

和

@Configurathtml" target="_blank">ion
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
//        http.csrf().disable();
        http.cors();
    }

    @Bean
    public CorsConfigurationSource corsConfigurationSource() {
        final CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(ImmutableList.of("*"));
        configuration.setAllowedMethods(ImmutableList.of("HEAD",
                "GET", "POST", "PUT", "DELETE", "PATCH"));
        // setAllowCredentials(true) is important, otherwise:
        // The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'.
        configuration.setAllowCredentials(true);
        // setAllowedHeaders is important! Without it, OPTIONS preflight request
        // will fail with 403 Invalid CORS request
        configuration.setAllowedHeaders(ImmutableList.of("Authorization", "Cache-Control", "Content-Type"));
        final UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}

但这一次，我在控制台中看到的错误变成了

已被CORS策略阻止：“Access Control Allow Origin”标头包含多个值“*，*”，但只允许一个值。

所以，这是我达到的最后一点。我如何解决关于多个值的最后一个错误？每次我处理这个问题，我都提前一步，错误会改变，但它仍然存在。

Answer 1

只需将此添加到您的WebSecurity配置适配器

@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    
/*@Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedMethods("HEAD", "GET", "PUT", "POST", "DELETE", "PATCH");
    }*/ not needed

@Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            // by default uses a Bean by the name of corsConfigurationSource
            .cors(withDefaults())
            ...
    }

    @Bean
    CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(Arrays.asList("https://localhost:5000"));// if your front end running on localhost:5000
        configuration.setAllowedMethods(Arrays.asList("GET","POST"));
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}

确保除了上面的代码之外，您没有任何其他过滤器或cors注释

Spring Security留档中的Spring CORS部分。

如果您没有使用Spring Security：

java prettyprint-override">package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }


    @Bean
    public WebMvcConfigurer corsConfigurer() {
        return new WebMvcConfigurer() {
            @Override
            public void addCorsMappings(CorsRegistry registry) {
                registry
                .addMapping("/**")
                .allowedOrigins("*","http://localhost:5000");// list all domains
            }
        };
    }
}