如果参数存在而没有值选择器错误，我如何在集合变量（Mule 4）内进行验证？

我使用的是Mule 4，当有效负载是字符串而不是以下结构时，我有一个值错误选择器：

{"status": 0, "content": {"status": "201",...........

我在Mule 4中使用一个set变量，给出以下值：

<set-variable value="#[if (payload.content? and payload.content.status? and payload.content.status &gt;= 200) payload.content.status else 500]" doc:name="Set Status" doc:id="e9ce4fd1-9664-4401-b9a2-e47913b689af" variableName="httpStatus"/>

但有时服务器可以回答“未授权”之类的字符串，则payload.content不存在，只是一个字符串

当有效负载是字符串时，Set变量给我这个错误

"\"You called the function 'Value Selector' with these arguments: \n 1: Binary (\"Richiesta Non Autorizzata\" as Binary {encoding: \"UTF-8\", mediaType: \"text/ht...)\n 2: Name (\"content\")\n\nBut it expects one of these combinations:\n (Array, Name)\n (Array, String)\n (Date, Name)\n (DateTime, Name)\n (LocalDateTime, Name)\n (LocalTime, Name)\n (Object, Name)\n (Object, String)\n (Period, Name)\n (Time, Name)\n\n1| if (payload.content? and payload.content.status? and payload.content.status >= 200) payload.content.status else 500\n ^^^^^^^^^^^^^^^\nTrace:\n at main (line: 1, column: 5)\" evaluating expression: \"if (payload.content? and payload.content.status? and payload.content.status >= 200) payload.content.status else 500\".",

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使用

payload.content.status default{}

或者您可以将其默认为字符串或其他值，以便稍后进行比较和使用

我能想到的最好方法是不检查字段是否存在检查值是否为Object，然后您可以确保

.status

正常工作

if (payload.content is Object and payload.content.status? and payload.content.status >= 200) 
    payload.content.status 
else 500

if (payload.content is Object and payload.content.status? and payload.content.status >= 200) 
    payload.content.status 
else 500