Spring integration Spring集成ServiceActivator输出

使用与中所述相同的设置，我无法从后端API获得响应，目标是通过HTTP上传文件并将其存储在MongoDB中，需要时通过使用特定HTTP头的get调用检索文件

服务激活器中的方法返回相同的请求消息。。。将返回类型从文档更改为有效负载中包含文档的消息，但不会生成不同的行为，基本上，文件保存在MongoDB中http调用正常，但不会向前端发送响应

另一方面，使用纯XML配置，我不确定如何从UploadedMultiPartFile提取文件并将其转发到后端API。请参阅下面的另一个设置

public Document uploadFile(Message inMessage) throws IOException {

LinkedMultiValueMap<String,Object> multipartRequest = (LinkedMultiValueMap<String, Object>) inMessage.getPayload();

final String filename = ((UploadedMultipartFile) multipartRequest.getFirst("file")).getOriginalFilename();

RestTemplate template = new RestTemplate();
MultiValueMap<String, Object> multipartMap = new LinkedMultiValueMap<String, Object>();
multipartMap.add("name", filename);
multipartMap.add("filename", filename);

byte[] bytes = ((UploadedMultipartFile) multipartRequest.getFirst("file")).getBytes();
ByteArrayResource contentsAsResource = new ByteArrayResource(bytes){
    public String getFilename(){
        return filename;
    }
};

multipartMap.add("file", contentsAsResource);
Document result = template.postForObject("http://localhost:5050/api/upload", multipartMap, Document.class);

return result; // which isn't null!

}

XML设置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:int="http://www.springframework.org/schema/integration"
       xmlns:int-http="http://www.springframework.org/schema/integration/http"
       xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/integration/http http://www.springframework.org/schema/integration/http/spring-integration-http.xsd">

<bean id="multipartResolver"
      class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

<bean id="headerMapper" class="org.springframework.integration.http.support.DefaultHttpHeaderMapper">
    <property name="inboundHeaderNames" value="*"/>
    <property name="outboundHeaderNames" value="*"/>
    <property name="userDefinedHeaderPrefix" value=""/>
</bean>

<int:channel id="http.frontend.rx"/>
<int:channel id="http.frontend.tx"/>
<int:channel id="http.backend.mysql"/>
<int:channel id="http.backend.mongo"/>

<int-http:inbound-gateway
        id="frontEndToMySQLXX"
        request-channel="http.frontend.rx"
        reply-channel="http.frontend.tx"
        header-mapper="headerMapper"
        path="/gateway"
        supported-methods="GET,POST,PUT,DELETE"/>

<int:router id="frontEndRouter" input-channel="http.frontend.rx" expression="headers.service">
    <int:mapping value="json" channel="http.backend.mysql" />
    <int:mapping value="file" channel="http.backend.mongo" />
</int:router>

<int-http:outbound-gateway
        id="toMongoDB"
        request-channel="http.backend.mongo"
        reply-channel="http.frontend.tx"
        url="http://localhost:5050/api/{path}"
        http-method-expression="headers.http_requestMethod"
        header-mapper="headerMapper"
        expected-response-type="byte[]">
    <int-http:uri-variable name="path" expression="headers['urlpath']"/>
</int-http:outbound-gateway>

<int-http:outbound-gateway
        id="toMySQLDB"
        request-channel="http.backend.mysql"
        reply-channel="http.frontend.tx"
        url="http://localhost:7070/api/{path}"
        http-method-expression="headers.http_requestMethod"
        expected-response-type="java.lang.String"
        charset="UTF-8">
    <int-http:uri-variable name="path" expression="headers['urlpath']"/>
</int-http:outbound-gateway>

---

我决定最终通过一个单独的URL处理多部分文件上传，在Spring MVC中创建一个伪端点，将多部分文件发布到该URL，并将该请求转发到后端系统，如果我可以通过http出站网关处理多部分文件上传，那就太好了。。。但事实并非如此

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:int="http://www.springframework.org/schema/integration"
       xmlns:int-http="http://www.springframework.org/schema/integration/http"
       xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/integration/http http://www.springframework.org/schema/integration/http/spring-integration-http.xsd">

<bean id="multipartResolver"
      class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

<bean id="headerMapper" class="org.springframework.integration.http.support.DefaultHttpHeaderMapper">
    <property name="inboundHeaderNames" value="*"/>
    <property name="outboundHeaderNames" value="*"/>
    <property name="userDefinedHeaderPrefix" value=""/>
</bean>

<int:channel id="http.frontend.rx"/>
<int:channel id="http.frontend.tx"/>
<int:channel id="http.backend.mysql"/>
<int:channel id="http.backend.mongo"/>

<int-http:inbound-gateway
        id="frontEndToMySQLXX"
        request-channel="http.frontend.rx"
        reply-channel="http.frontend.tx"
        header-mapper="headerMapper"
        path="/gateway"
        supported-methods="GET,POST,PUT,DELETE"/>

<int:router id="frontEndRouter" input-channel="http.frontend.rx" expression="headers.service">
    <int:mapping value="json" channel="http.backend.mysql" />
    <int:mapping value="file" channel="http.backend.mongo" />
</int:router>

<int-http:outbound-gateway
        id="toMongoDB"
        request-channel="http.backend.mongo"
        reply-channel="http.frontend.tx"
        url="http://localhost:5050/api/{path}"
        http-method-expression="headers.http_requestMethod"
        header-mapper="headerMapper"
        expected-response-type="byte[]">
    <int-http:uri-variable name="path" expression="headers['urlpath']"/>
</int-http:outbound-gateway>

<int-http:outbound-gateway
        id="toMySQLDB"
        request-channel="http.backend.mysql"
        reply-channel="http.frontend.tx"
        url="http://localhost:7070/api/{path}"
        http-method-expression="headers.http_requestMethod"
        expected-response-type="java.lang.String"
        charset="UTF-8">
    <int-http:uri-variable name="path" expression="headers['urlpath']"/>
</int-http:outbound-gateway>