Json to XML with attributes rather than elements

Question

I need to parse an Json like:

{
"operacion": "ingresarOrdenBilateral",
"agente" : "0062",
"comitente" : 7211,
"fechaOrigen" : "2021-09-23T16:51:27.873-03:00",
"tipo" : "V",
"instrumento" : "GD30",
"tipoVenc" : "24",
"precio" : "100000000",
"cantidad" : "1",
"idOrigen" : 10699570
"ejecucion" : "SINCRONICA"
}

To this XML:

<ingresarOrdenBilateral 
agente="150" idOrigen="10039" fechaOrigen="2018-08-16T11:28:08.495-03:00" tipo="V" 
instrumento="AA17" tipoVenc="24" cantidad="1000000" precio="1625" formaOp="C" 
ejecucion="SINCRONICA"/>

I have tried the library xmltodict and dicttoxml but I can't manage to get XML using attributes rather than elements. Also I think that the XML format is not standard.

Thanks!

Show your code, and explain what you mean by *"I think that the XML format is not standard"*. — Tomalak, Oct 09 '21 at 07:30
I've edited the question to what I think is the real problem -- using attributes vs elements; the fact that the element is then self-closing is an irrelevance — Michael Kay, Oct 09 '21 at 07:35
@Methizul, where this data stored? Do you read it from file? Or you retrieve it from some server? — Olvin Roght, Oct 10 '21 at 14:36

score 0 · Answer 1 · answered Oct 09 '21 at 07:34

Firstly, using attributes rather than child elements is completely standard for this kind of structure. It's perhaps a little less common than using child elements, but it's not really unusual and it's certainly not non-standard.

Secondly, standard off-the-shelf converters between JSON and XML never give you enough control to produce exactly the target structure that you want. If you want a particular XML format, then you have to be prepared to do a transformation on the result, which is usually very easy to achieve with XSLT.

If you use XSLT 3.0 then you can do the JSON-to-XML conversion and the subsequent transformation within a single stylesheet; but otherwise, using your favourite library converter followed by an XSLT (1.0+) conversion is straightforward enough. You'll find plenty of examples of stylesheets that convert XML elements to attributes.

score 0 · Answer 2 · answered Oct 09 '21 at 17:08

If the XML is that simple the code below is able to do the job

data = {
"operacion": "ingresarOrdenBilateral",
"agente" : "0062",
"comitente" : 7211,
"fechaOrigen" : "2021-09-23T16:51:27.873-03:00",
"tipo" : "V",
"instrumento" : "GD30",
"tipoVenc" : "24",
"precio" : "100000000",
"cantidad" : "1",
"idOrigen" : 10699570,
"ejecucion" : "SINCRONICA"
}

xml = '<root>' + ' '.join(f'"{k}"="{v}"' for k,v in data.items()) + '</root>'
print(xml)

output

<?xml version="1.0" encoding="UTF-8"?>
<root>"operacion"="ingresarOrdenBilateral" "agente"="0062" "comitente"="7211" "fechaOrigen"="2021-09-23T16:51:27.873-03:00" "tipo"="V" "instrumento"="GD30" "tipoVenc"="24" "precio"="100000000" "cantidad"="1" "idOrigen"="10699570" "ejecucion"="SINCRONICA"</root>

Your code won't produce output you attached. Your code won't produce output attached to question. Your code won't produce valid XML at all. — Olvin Roght, Oct 09 '21 at 22:36

Olvin Roght · Accepted Answer · 2021-10-10T14:50:46.427

Well, it can be done in one line using built-in xml.etree.ElementTree:

import xml.etree.ElementTree as ET

data = {
    "operacion": "ingresarOrdenBilateral",
    "agente": "0062",
    "comitente": 7211,
    "fechaOrigen": "2021-09-23T16:51:27.873-03:00",
    "tipo": "V",
    "instrumento": "GD30",
    "tipoVenc": "24",
    "precio": "100000000",
    "cantidad": "1",
    "idOrigen": 10699570,
    "ejecucion": "SINCRONICA"
}
ET.dump(ET.Element(data.pop("operacion"), {k: str(v) for k, v in data.items()}))

Output:

<ingresarOrdenBilateral agente="0062" comitente="7211" fechaOrigen="2021-09-23T16:51:27.873-03:00" tipo="V" instrumento="GD30" tipoVenc="24" precio="100000000" cantidad="1" idOrigen="10699570" ejecucion="SINCRONICA" />

Upd. Assuming you're loading this JSON data either from file or server it's possible to pass str() to parse_int argument of json.load()/json.loads()/requests.Response.json(). It will force int fields to be parsed as str, so we can omit dict comprehension I've used in code above:

import json
import xml.etree.ElementTree as ET

str_data = '''{
    "operacion": "ingresarOrdenBilateral",
    "agente": "0062",
    "comitente": 7211,
    "fechaOrigen": "2021-09-23T16:51:27.873-03:00",
    "tipo": "V",
    "instrumento": "GD30",
    "tipoVenc": "24",
    "precio": "100000000",
    "cantidad": "1",
    "idOrigen": 10699570,
    "ejecucion": "SINCRONICA"
}'''
data = json.loads(str_data, parse_int=str)
ET.dump(ET.Element(data.pop("operacion"), data))

There're also parse_float and parse_constant which you can use in same way (if needed, ofc).

Json to XML with attributes rather than elements

3 Answers3