Attributes

XML can carry more information (i.e. metadata) than JSON, that is why a convention in the format of a converting json document is needed to match the original XML semantics. In jsomark, attributes are defined with the symbol “&”:

from jsomark import json_to_xml

json_data = {
    "Device": {
        "Reference": {
            "&": {"ID": "XYZ2020", "Serial": "S10987"}
        }
    }
}

xml_data = json_to_xml(json_data)

assert xml_data == (
    b'<Device><Reference ID="XYZ2020" Serial="S10987"/></Device>')

If the key with attributes also has a text content, then the symbol “#” should be used to carry it:

from jsomark import json_to_xml

json_data = {
    "Employee": {
        "Company": {
            "&": {"VAT": "900123765"},
            "#": "Servagro"
        }
    }
}

xml_data = json_to_xml(json_data)

assert xml_data == (
    b'<Employee><Company VAT="900123765">Servagro</Company></Employee>')

Lists

Lists in the JSON document are interpreted as repeating elements inside the generated XML.

from jsomark import json_to_xml

json_data = {
    "Order": {
        "Line": [
            {"&": {"ID": "1"}, "#": "Chocolate Ice Cream"},
            {"&": {"ID": "2"}, "#": "Banana Split"},
            {"&": {"ID": "3"}, "#": "Caramel Cake"}
        ]
    }
}

xml_data = json_to_xml(json_data)

assert xml_data == (
    b'<Order><Line ID="1">Chocolate Ice Cream</Line>'
    b'<Line ID="2">Banana Split</Line>'
    b'<Line ID="3">Caramel Cake</Line></Order>')

Namespaces

In jsomark, namespaces are provided as a separate dictionary whose keys are the prefixes that must be used in the json document itself. The default namespace should be set in the ‘None’ key of the namespaces dictionary and its keys in the json document don’t have to be prefixed:

from jsomark import json_to_xml

namespaces = {
    None: 'urn:loc.gov:books',
    'isbn': 'urn:ISBN:0-395-36341-6'
}

json_data = {
    "book": {
        "title": "Cheaper by the Dozen",
        "isbn:number": 1568491379
    }
}

xml_data = json_to_xml(json_data, namespaces=namespaces)

assert xml_data == (
    b'<book xmlns="urn:loc.gov:books" xmlns:isbn="urn:ISBN:0-395-36341-6">'
    b'<title>Cheaper by the Dozen</title>'
    b'<isbn:number>1568491379</isbn:number></book>'