带有URL表单编码正文的Mule ESB HTTP POST请求

Question

我是Mule ESB的新手，并尝试向REST服务发送post请求。请求的主体是字符串形式，请求应该是x-www-form-urlencoded。我将有效负载设置为我的参数并将请求发送给REST服务,但我得到了一个异常：

Failed to invoke REST service "http://username:password@192.168.10.252/api/rest/session/login.json". Message payload is of type: String

我的Rest URL是:(#[restURL])${dms.host}/api/Rest/session/login.json

我的参数是（设置为有效载荷#[restBody]):username=user&password=pass

<sub-flow name="RESTrequestToDMS" doc:name="RESTrequestToDMS" processingStrategy="synchronous">
    <set-variable variableName="originalMessage" value="#[payload]" doc:name="Backup original message"/>
    <logger message="#[restBody]" level="INFO" doc:name="Logger"/>
    <choice doc:name="Choice">
        <when expression="restHTTPmethod == 'POST'">
            <processor-chain>    
                <set-payload value="#[restBody]" doc:name="Set Payload"/>           
                <http:rest-service-component httpMethod="POST" serviceUrl="http://${dms.user}:${dms.pass}@#[restURL]"></http:rest-service-component>
            </processor-chain>
        </when>
        <when expression="restHTTPmethod == 'GET'">
            <processor-chain>
                <http:rest-service-component httpMethod="GET" serviceUrl="http://${dms.user}:${dms.pass}@#[restURL]?#[restBody]"></http:rest-service-component>
            </processor-chain>
        </when>
        <otherwise>
            <processor-chain>
                <logger message="Unknown http method type is provided! " level="ERROR" doc:name="Logger"/>
            </processor-chain>
        </otherwise>
    </choice>
    <json:json-to-object-transformer returnClass="java.util.Map" doc:name="JSON to Object"/>
    <echo-component doc:name="Echo"/>
    <set-variable variableName="RESTResponse" value="#[payload]" doc:name="set RESTResponse"/>
    <set-payload value="#[flowVars['originalMessage']]" doc:name="Restore Original Message"/>
</sub-flow>

谁能帮我弄清楚这件事吗？

提前多谢了。

注：根据David的回复更新。

------------更新-------------------------------

所以现在，出于测试的目的，我修改了流，如下所示：

<set-payload value="#[restBody]" doc:name="Set Payload"/>
<custom-transformer class="de.mfg.osii.http.StringToURIParametersMapTransformer" doc:name="String To URI Parameters"/>  
<http:rest-service-component httpMethod="POST" serviceUrl="http://${dms.user}:${dms.pass}@#[restURL]">
    <http:requiredParameter key="username" value="#[payload.get('username')]" />
    <http:requiredParameter key="password" value="#[payload.get('password')]" />
</http:rest-service-component>  

因此，现在的有效负载是：{username=user,password=pass}，但现在当我尝试运行它时，我得到以下错误：

1. Failed to invoke REST service "http://user:pass@192.168.10.252/api/rest/session/login.json". Message payload is of type: LinkedHashMap (org.mule.transport.http.components.RestServiceException)

更新：通过添加一个值为“application/x-www-form-urlencoded”的message-property“content-type”，刚刚解决了上述问题，即异常。

不过，下面的最后一部分对我来说仍然是个谜：）

另一件事是，正如我在对David回答的注释中所述，我是否可以以自适应的方式为rest组件添加所需的参数？更清楚地说，我不想为每一个不同的请求创建不同的流。我在有效载荷中有参数映射，所以我想对它们进行迭代，并将它们放入所需的参数中。这样的事情可能发生吗？

提前多谢了！

------------更新-------------------------------

所以，我修改了我的流程并使用了David的建议。然而，现在，我得到一个HTTP405错误（方法不允许）。但我肯定我发帖到正确的地址和正确的内容类型。这是什么原因呢？有人有主意吗？

这个流中的有效负载是一个字符串（url编码的参数），比如->

SessionID=9EUB9GM7K7OC1UB81DHEF6T46Q&XML=%3CobjectList%3E%3CFolderObject%3E%3CaddToFolder%20RefType%3D%22Path%22%20ClassName%3D%22FolderObject%22%3E%3C！%5BCData%5B%2FoldDerPath%5D%5D%3E%3C%2FaddToFolder%3E%3C！%5BCData%5Baaa%5D%5D%3E%3C%2Name%3E%3C%3C

<flow name="RESTrequestToDMS" doc:name="RESTrequestToDMS" processingStrategy="synchronous">
    <set-variable variableName="originalMessage" value="#[payload]" doc:name="Backup original message"/>
    <choice doc:name="Choice">
        <when expression="restHTTPmethod == 'POST'">
            <processor-chain>
                <set-payload value="#[restBody]" doc:name="Set Payload"/>
                <logger message="The payload before http post is: #[message.payload]" level="INFO" doc:name="Logger"/>
                <http:outbound-endpoint  exchange-pattern="request-response" doc:name="HTTP" address="http://#[restURL]"  user="${dms.user}" password="${dms.pass}" contentType="application/x-www-form-urlencoded">
                </http:outbound-endpoint>
            </processor-chain>
        </when>
        <when expression="restHTTPmethod == 'GET'">
            <processor-chain>
                <http:outbound-endpoint method="GET"  exchange-pattern="request-response" doc:name="HTTP" address="http://#[restURL]?#[restBody]"  user="${dms.user}" password="${dms.pass}" contentType="application/x-www-form-urlencoded">
        </http:outbound-endpoint>
            </processor-chain>
        </when>
        <otherwise>
            <processor-chain>
                <logger message="Unknown http method type is provided! " level="ERROR" doc:name="Logger"/>
            </processor-chain>
        </otherwise>
    </choice>
    <echo-component doc:name="Echo"/>
    <choice doc:name="Choice">
        <when expression="payload != null &amp;&amp; payload != empty &amp;&amp; payload != ''">
            <processor-chain>
                <json:json-to-object-transformer doc:name="JSON to Object" returnClass="java.util.Map"/>
                <set-variable variableName="RESTResponse" value="#[payload]" doc:name="set RESTResponse"/>
            </processor-chain>
        </when>
        <otherwise>
            <processor-chain>
                <logger message="The payload is null or empty! HTTP response code is: #[message.inboundProperties['http.status']]" level="INFO" doc:name="Logger"/>
                <set-variable variableName="RESTResponse" value="#[message.inboundProperties['http.status']]" doc:name="Set HTTP Status Code"/>
            </processor-chain>
        </otherwise>
    </choice>
    <set-payload value="#[flowVars['originalMessage']]" doc:name="Restore Original Message"/>
</flow> 

Answer 1

以下是如何传递参数以通过rest-service-component进行URL编码：

<http:rest-service-component httpMethod="POST"
    serviceUrl="http://${dms.user}:${dms.pass}@#[restURL]">
    <http:requiredParameter key="username" value="user" />
    <http:requiredParameter key="password" value="pass" />
</http:rest-service-component>