Question

我尝试通过检查变量的null并在结果中设置来实现一个简单的循环。

我的骡子流部分如下所示。

数据库（选择） - ＆gt;转换消息（DataWeave-转换为xml）

数据库的价值如下：

Book1 Book2 Book3 Book4 Book5
abc   cde   fgh   ijk   lmn
opq   rst   NULL  NULL  NULL

Dataweaver代码如下所示：

ns0#LibraryDetails:{
                ns0#User: payload."Book1",
                ns0#User: payload."Book2",
                ns0#User: payload."Book3",
                ns0#User: payload."Book4",
                ns0#User: payload."Book5"
            }

预期的输出1是

<LibraryDetails>
   <User>abc</User>
   <User>cde</User>
   <User>fgh</User>
   <User>ijk</User>
   <User>lmn</User>
</LibraryDetails>

预期的输出2是

<LibraryDetails>
   <User>opq</User>
   <User>rst</User>
</LibraryDetails>

我们如何才能仅转义空值并在数据编织中创建循环。我也试过了地图功能。你能否就此展示一些亮点。

Answer 1

要获得预期输出，请使用map，然后使用skipNullOn="everywhere"，如果您希望所有元素都使用该逻辑。以下给出了您的预期输出

%dw 1.0
    %output application/xml skipNullOn="everywhere"

    %namespace ns0 http://something.com
    ---

    ns0#LibraryDetails: { (payload map {
          ns0#User: $.Book1,
          ns0#User: $.Book2,
          ns0#User: $.Book3,
          ns0#User: $.Book4,
          ns0#User: $.Book5
    } )  }

Answer 2

你可以试试这个：

ns0#LibraryDetails:{
                ns0#User: when null != payload."Book1" then payload."Book1" ,
                ns0#User: when null != payload."Book2"then payload."Book2",
                ns0#User: when null != payload."Book3"then payload."Book3",
                ns0#User: when null != payload."Book4"then payload."Book4",
                ns0#User: when null != payload."Book5"then payload."Book5"
            }

ELSE：使用beow语句：％output application / xml skipNullOn =“everywhere”

数据weaver循环和检查使用ESB mule

2 个答案: