Spring集成-如何使用http出站网关发送POST参数

Question

我试图使用Spring Integration和HTTP出站网关组合一个非常简单的HTTP POST示例。
我需要能够发送带有一些POST参数的HTTP POST消息，就像使用curl:

$ curl -d 'fName=Fred&sName=Bloggs' http://localhost

如果向接口方法发送一个简单的字符串作为参数，我可以让它工作（没有POST参数），但我需要发送一个pojo，其中pojo的每个属性都成为POST参数。

我有以下SI配置：

<?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/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
    http://www.springframework.org/schema/integration/http http://www.springframework.org/schema/integration/http/spring-integration-http.xsd">

    <int:gateway id="requestGateway"
             service-interface="RequestGateway"
             default-request-channel="requestChannel"/>

    <int:channel id="requestChannel"/>

    <int-http:outbound-gateway request-channel="requestChannel"
                           url="http://localhost"
                           http-method="POST"
                           expected-response-type="java.lang.String"/>

</beans>

我的RequestGateway接口如下所示：

public interface RequestGateway {
    String echo(Pojo request);
}

我的POJO类如下所示：

public class Pojo {
    private String fName;
    private String sName;

    public Pojo(String fName, String sName) {
        this.fName = fName;
        this.sName = sName;
    }

    .... getters and setters
}

public class HttpClientDemo {

    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("/si-email-context.xml");
        RequestGateway requestGateway = context.getBean("requestGateway", RequestGateway.class);

        Pojo pojo = new Pojo("Fred", "Bloggs");
        String reply = requestGateway.echo(pojo);
        System.out.println("Replied with: " + reply);
    }
}

org.springframework.web.client.RestClientException: Could not write request: no suitable HttpMessageConverter found for request type [Pojo] and content type [application/x-java-serialized-object]

我为此搜索了大量的Google，但找不到任何使用出站网关发送HTTP POST参数的示例（我可以找到许多关于设置HTTP头的示例，但这不是我在这里试图做的）
我唯一找到的是Spring-Integration：如何将POST请求参数传递给HTTP-Outbount，但这是一个稍微不同的用例，因为OP试图发送他的pojo的JSON表示，而我不是，答案是关于设置头，而不是POST参数。

如有任何帮助，将不胜感激；
谢谢
Nathan

Answer 1

由于@jra077中关于content-type的指针，我就是这样解决这个问题的。

我的SI配置现在看起来如下所示--重要的一点是添加content-type标头：

<?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/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
    http://www.springframework.org/schema/integration/http http://www.springframework.org/schema/integration/http/spring-integration-http.xsd">

    <int:gateway id="requestGateway"
             service-interface="RequestGateway"
             default-request-channel="requestChannel">
        <int:method name="sendConfirmationEmail">
            <int:header name="Content-Type" value="application/x-www-form-urlencoded"/>
        </int:method>
    </int:gateway>

    <int:channel id="requestChannel"/>

    <int-http:outbound-gateway request-channel="requestChannel"
                           url="http://localhost"
                           http-method="POST"
                           expected-response-type="java.lang.String"/>

</beans>

然后，我更改了接口，将映射作为参数，而不是POJO：

public interface RequestGateway {
    String echo(Map<String, String> request);
}

public class HttpClientDemo {

    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("/si-email-context.xml");
        RequestGateway requestGateway = context.getBean("requestGateway", RequestGateway.class);

        Pojo pojo = new Pojo("Fred", "Bloggs");

        Map<String, String> requestMap = new HashMap<String, String>();
        requestMap.put("fName", pojo.getFName());
        requestMap.put("sName", pojo.getSName());

        String reply = requestGateway.echo(requestMap);
        System.out.println("Replied with: " + reply);
    }
}

要使用http出站网关发送POST参数，需要将Content-type设置为application/x-www-form-urlencode，并且需要传递键/值对的映射。