CORS

Spring Framework 提供對 CORS 的一流支援。CORS 必須在 Spring Security 之前處理，因為預檢請求不包含任何 Cookie（即 JSESSIONID）。如果請求不包含任何 Cookie，且 Spring Security 在前，則請求會判斷使用者未通過身份驗證（因為請求中沒有 Cookie）並拒絕它。

確保首先處理 CORS 的最簡單方法是使用 CorsFilter。使用者可以透過提供 CorsConfigurationSource 將 CorsFilter 與 Spring Security 整合。請注意，只有在存在 UrlBasedCorsConfigurationSource 實例時，Spring Security 才會自動配置 CORS。例如，以下程式碼將在 Spring Security 中整合 CORS 支援

Java
Kotlin

@Bean
UrlBasedCorsConfigurationSource corsConfigurationSource() {
    CorsConfiguration configuration = new CorsConfiguration();
    configuration.setAllowedOrigins(Arrays.asList("https://example.com"));
    configuration.setAllowedMethods(Arrays.asList("GET","POST"));
    UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
    source.registerCorsConfiguration("/**", configuration);
    return source;
}

@Bean
fun corsConfigurationSource(): UrlBasedCorsConfigurationSource {
    val configuration = CorsConfiguration()
    configuration.allowedOrigins = listOf("https://example.com")
    configuration.allowedMethods = listOf("GET", "POST")
    val source = UrlBasedCorsConfigurationSource()
    source.registerCorsConfiguration("/**", configuration)
    return source
}

以下列表在 XML 中執行相同的操作

<http>
	<cors configuration-source-ref="corsSource"/>
	...
</http>
<b:bean id="corsSource" class="org.springframework.web.cors.UrlBasedCorsConfigurationSource">
	...
</b:bean>

如果您使用 Spring MVC 的 CORS 支援，則可以省略指定 CorsConfigurationSource，而 Spring Security 將使用提供給 Spring MVC 的 CORS 組態配置

Java
Kotlin

@Configuration
@EnableWebSecurity
public class WebSecurityConfig {

	@Bean
	public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
		http
			// if Spring MVC is on classpath and no CorsConfigurationSource is provided,
			// Spring Security will use CORS configuration provided to Spring MVC
			.cors(withDefaults())
			...
		return http.build();
	}
}

@Configuration
@EnableWebSecurity
open class WebSecurityConfig {
    @Bean
    open fun filterChain(http: HttpSecurity): SecurityFilterChain {
        http {
            // if Spring MVC is on classpath and no CorsConfigurationSource is provided,
            // Spring Security will use CORS configuration provided to Spring MVC
            cors { }
            // ...
        }
        return http.build()
    }
}

以下列表在 XML 中執行相同的操作

<http>
	<!-- Default to Spring MVC's CORS configuration -->
	<cors />
	...
</http>

如果您有多個 CorsConfigurationSource Bean，Spring Security 將不會自動為您配置 CORS 支援，那是因為它無法決定要使用哪一個。如果您想為每個 SecurityFilterChain 指定不同的 CorsConfigurationSource，您可以將其直接傳遞到 .cors() DSL 中。

Java
Kotlin

@Configuration
@EnableWebSecurity
public class WebSecurityConfig {

	@Bean
	@Order(0)
	public SecurityFilterChain apiFilterChain(HttpSecurity http) throws Exception {
		http
			.securityMatcher("/api/**")
			.cors((cors) -> cors
				.configurationSource(apiConfigurationSource())
			)
			...
		return http.build();
	}

	@Bean
	@Order(1)
	public SecurityFilterChain myOtherFilterChain(HttpSecurity http) throws Exception {
		http
			.cors((cors) -> cors
				.configurationSource(myWebsiteConfigurationSource())
			)
			...
		return http.build();
	}

	UrlBasedCorsConfigurationSource apiConfigurationSource() {
		CorsConfiguration configuration = new CorsConfiguration();
		configuration.setAllowedOrigins(Arrays.asList("https://api.example.com"));
		configuration.setAllowedMethods(Arrays.asList("GET","POST"));
		UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
		source.registerCorsConfiguration("/**", configuration);
		return source;
	}

	UrlBasedCorsConfigurationSource myWebsiteConfigurationSource() {
		CorsConfiguration configuration = new CorsConfiguration();
		configuration.setAllowedOrigins(Arrays.asList("https://example.com"));
		configuration.setAllowedMethods(Arrays.asList("GET","POST"));
		UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
		source.registerCorsConfiguration("/**", configuration);
		return source;
	}

}

@Bean
fun corsConfigurationSource(): UrlBasedCorsConfigurationSource {
    val configuration = CorsConfiguration()
    configuration.allowedOrigins = listOf("https://example.com")
    configuration.allowedMethods = listOf("GET", "POST")
    val source = UrlBasedCorsConfigurationSource()
    source.registerCorsConfiguration("/**", configuration)
    return source
}