Filter during parsing?

I would like to be able to parse a subset of an XML document, for example, if I don’t need the entire document, but need a particular deeply-nested tree starting at some path within the XML document.

Is there a way to do this using the new postprocessor feature mentioned in #6? I don’t see a way to exclude elements that way, but it’s possible I am misreading the docs/code.

[martinblech]

I get it. In this case, you should use a postprocessor, not the streaming mode. The postprocessing function gets three arguments in (path, key and value) and must return a (key, value) tuple or None to skip the node altogether.

If you want to skip odd <item>s, you should do something like this:

xml = '''
<doc>
    <item>Item1</item>
    <item>Item2</item>
    <item>Item3</item>
    <item>Item4</item>
</doc>'''

class SkipOddValues:
    def __init__(self, key):
        self.key = key
        self.count = 0

    def __call__(self, path, key, value):
        if key != self.key:
            return key, value
        self.count += 1
        if self.count % 2 == 1:
            return None
        else:
            return key, value

doc = xmltodict.parse(xml, postprocessor=SkipOddValues('item'))

[martinblech]

Welcome!