如何在Node JS API中处理多个不同格式的XML有效负载

Question

I have to accept different types of xml formats in the node api, based on the value that is defined need to perform respective operations.

Here is the code which I'm trying:

var xmlparser = require('express-xml-bodyparser');
    app.post('/xmlparser',xmlparser({trim: false, explicitArray: false}),function(request,reply){
    var data = JSON.stringify(request.body);
    var arr_data =JSON.parse(data);
    //code to access and display values from the xml

    console.log("xml 1:"+arr_data['ps0:tfg']['ps0:header']['ps1:messageid']);
    console.log("xml 2:"+arr_data['ps1:hls']['ps1:header']['ps1:messageid']);
})

Here are the 2 different xml, that takes as an input.

xml 1:
        <?xml version="1.0" encoding="UTF-8"?>
    <ps0:TFG xmlns:ns0="http://www.google.com/LOGO/Common">
    <ps0:Header version="1.0" xmlns:ns1="http://www.google.com/LOGO/Common">
    <ps1:MessageId>MESSAGE001</ns1:MessageId>
    </ps0:Header>
    </ns0:TFG>

xml 2:    
    <?xml version="1.0" encoding="UTF-8"?>
    <ps0:HLS xmlns:ns0="http://www.google.com/LOGO/Common">
    <ps0:Header version="1.0" xmlns:ns1="http://www.google.com/LOGO/Common">
    <ps1:MessageId>MESSAGE001</ns1:MessageId>
    </ps0:Header>
    </ps0:HLS>

I'm accepting different formats with in the same code as mentioned above, if i pass xml 1, xml 1 printing fine. if i pass the xml 2 as input, execution stops at 1st console log as the index is not available.

How can we handle this condition?

To resolve this I need to keep some conditions, atleast if it is showing undefined then i can mark in the condition, problem code is not executing if index mismatches.

Update: I have tried implementing try catch as well, but still no luck.

Answer 1

The problem probably stems from the fact that both XML and Javascript/JSON are case-sensitive.

For example,

const c = { alpha: 42 };
console.log(c.alpha) // ---> 42
console.log(c.Alpha) // ---> undefined

Likewise, in XML <ns1:MESSAGEID> is not the same tag as <ns1:MessageId> .

It is possible that whatever package you're using to parse your XML is messing around with the case, but that seems highly unlikely to me - any package that does that would not be compliant with standards.