Converting request params from DataTables with Pyramid

Question

I'm using Pyramid to handle ajax requests from DataTable. The request params have keys that are passed in like this:

'columns[0][search]', 'columns[1][search]', 'columns[0][data]', 'columns[0][data]'

Is there a way to tell pyramid (or another python library) to parse these request params into a nested dict so it looks more like:

{'columns': {
    '0': {'search': X, 'data': X}, 
    '1': {'search': X, 'data': X},
}}

Answer 1

This works. It would be nice if I could return it as a set of nested MultiDicts so I could continue to use the getone() and getall() methods, but I don't seem to be able to instantiate the MultiDicts from pyramid.

def unflatten_multidict(multidict):
    d = {}
    for k in multidict.keys():
        m = re.match(r'^([^\[\]]+)((?:\[[^\[\]]+\])+)', k)
        if m:
            attr = m.group(1)
            lastd = d.setdefault(attr, {})
            subkeys = re.findall(r'\[([^\[\]]+)\]', m.group(2))
            for i, subkey in enumerate(subkeys):
                if i < len(subkeys) - 1:
                    lastd = lastd.setdefault(subkey, {})
                else:
                    lastd[subkey] = multidict.get(k)
        else:
            d[k] = multidict.get(k)

    return d