如何在 spring 集成 (DSL) 中公开 "Content-Disposition"？

Question

为了下载文件，我会将 "Content-Disposition" 添加到我的 responseHeader，但它不起作用。

响应不会有任何添加的属性。

    @Bean
    public ExpressionParser fileParser() {
        return new SpelExpressionParser();
    }

    @Bean
    public HeaderMapper<HttpHeaders> fileHeaderMapper() {
        return new DefaultHttpHeaderMapper();
    }

@Bean
    public IntegrationFlow httpGetFileDownload() {
        return IntegrationFlows.from(
                Http.inboundGateway("/api/files/download/{id}")
                        .requestMapping(r -> r.methods(HttpMethod.GET))
                        .statusCodeExpression(fileParser().parseExpression("T(org.springframework.http.HttpStatus).BAD_REQUEST"))
                        .payloadExpression(fileParser().parseExpression("#pathVariables.id"))
                        .crossOrigin(cors -> cors.origin("*").exposedHeaders("Content-Disposition", "content-disposition"))
                        .headerMapper(fileHeaderMapper())
                )
                .channel("http.file.download.channel")
                .handle("fileEndpoint", "download")
                .get();
    }



public Message<?> download(Message<Long> msg){
...

return MessageBuilder
                    .withPayload(resource)
                    .copyHeaders(msg.getHeaders())
                    .setHeader(STATUSCODE_HEADER, HttpStatus.OK)
                    .setHeader(HttpHeaders.CONTENT_DISPOSITION,"attachment;filename=" + file.getName())
                    .setHeader(HttpHeaders.CONTENT_TYPE, mimeType)
                    .setHeader(HttpHeaders.CONTENT_LENGTH, (int)file.length())
                    .build();
}

我得到的：

缓存控制："no-cache, no-store, max-age=0, must-revalidate"
内容类型："application/json"
过期：“0”
编译指示："no-cache"

Answer 1

你的问题 DefaultHttpHeaderMapper 默认为空。我认为可能是时候将 ctor 设置为 deprecated 以不允许从终端应用程序使用它了。或者进行一些验证以拒绝空的（未配置）DefaultHttpHeaderMapper...

如果您不对其进行自定义，那么使用 return new DefaultHttpHeaderMapper(); 的意义也令人困惑。 HttpRequestHandlingMessagingGateway:

里面有个默认的

private HeaderMapper<HttpHeaders> headerMapper = DefaultHttpHeaderMapper.inboundMapper();

要解决您的问题，您肯定需要使用此 inboundMapper() 工厂方法，它执行以下操作：

/**
 * Factory method for creating a basic inbound mapper instance.
 * This will map all standard HTTP request headers when receiving an HTTP request,
 * and it will map all standard HTTP response headers when sending an HTTP response.
 * @return The default inbound mapper.
 */
public static DefaultHttpHeaderMapper inboundMapper() {
    DefaultHttpHeaderMapper mapper = new DefaultHttpHeaderMapper();
    setupDefaultInboundMapper(mapper);
    return mapper;
}

setupDefaultInboundMapper() 非常重要：它为我们带来了一组 headers 从请求映射到响应。

如何在 spring 集成 (DSL) 中公开 "Content-Disposition"？

How can I expose the "Content-Disposition" in spring-integration (DSL)?

spring-integration

spring-integration-dsl

spring-integration-http