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pythonxml

How can I convert XML into a Python object?


I need to load an XML file and convert the contents into an object-oriented Python structure. I want to take this:

<main>
    <object1 attr="name">content</object>
</main>

And turn it into something like this:

main
main.object1 = "content"
main.object1.attr = "name"

The XML data will have a more complicated structure than that and I can't hard code the element names. The attribute names need to be collected when parsing and used as the object properties.

How can I convert XML data into a Python object?


Solution

  • It's worth looking at lxml.objectify.

    xml = """<main>
    <object1 attr="name">content</object1>
    <object1 attr="foo">contenbar</object1>
    <test>me</test>
    </main>"""
    
    from lxml import objectify
    
    main = objectify.fromstring(xml)
    main.object1[0]             # content
    main.object1[1]             # contenbar
    main.object1[0].get("attr") # name
    main.test                   # me
    

    Or the other way around to build xml structures:

    item = objectify.Element("item")
    item.title = "Best of python"
    item.price = 17.98
    item.price.set("currency", "EUR")
    
    order = objectify.Element("order")
    order.append(item)
    order.item.quantity = 3
    order.price = sum(item.price * item.quantity for item in order.item)
    
    import lxml.etree
    print(lxml.etree.tostring(order, pretty_print=True))
    

    Output:

    <order>
      <item>
        <title>Best of python</title>
        <price currency="EUR">17.98</price>
        <quantity>3</quantity>
      </item>
      <price>53.94</price>
    </order>