Spring Cloud - Zuul Proxy is producing a No 'Access-Control-Allow-Origin' ajax response | cors

The problem was NOT in Zuul, but in Spring Security.

Goto class SecurityConfig and add this code

@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {


    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
                .csrf().disable()
        http.cors();
    }

    @Bean
    CorsConfigurationSource corsConfigurationSource() {
        final UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        final CorsConfiguration config = new CorsConfiguration();
        config.setAllowCredentials(true);
        config.addAllowedOrigin(CorsConfiguration.ALL);
        config.addAllowedHeader("*");
        config.addAllowedMethod("OPTIONS");
        config.addAllowedMethod("HEAD");
        config.addAllowedMethod("GET");
        config.addAllowedMethod("PUT");
        config.addAllowedMethod("POST");
        config.addAllowedMethod("DELETE");
        config.addAllowedMethod("PATCH");
        source.registerCorsConfiguration("/**", config);
        return source;
    }

}

Then goto yml and add this code:

zuul: 

    ignored-headers: Access-Control-Allow-Credentials, Access-Control-Allow-Origin