Reduced urllib.parse_qsl implementation for MicroPython

urlparse.py

# -*- coding: utf-8 -*-

def parse_qsl(qs, keep_blank_values=False, strict_parsing=False,
              encoding='utf-8', errors='replace'):
    """Parse a query given as a string argument.

    Arguments:

    qs: percent-encoded query string to be parsed. May be a unicode
        string or a UTF-8 encoded byte-string.

    keep_blank_values: flag indicating whether blank values in
        percent-encoded queries should be treated as blank strings.  A
        true value indicates that blanks should be retained as blank
        strings.  The default false value indicates that blank values
        are to be ignored and treated as if they were  not included.

    strict_parsing: flag indicating what to do with parsing errors. If
        false (the default), errors are silently ignored. If true,
        errors raise a ValueError exception.

    encoding: specify how to decode percent-encoded sequences into Unicode
        characters.

    Returns a list of (name, value) tuples.

    """
    if isinstance(qs, bytes):
        qs = qs.decode('utf-8')

    pairs = [s2 for s1 in qs.split('&') for s2 in s1.split(';')]
    r = []

    for name_value in pairs:
        if not name_value and not strict_parsing:
            continue

        nv = name_value.split('=', 1)

        if len(nv) != 2:
            if strict_parsing:
                raise ValueError("bad query field: %r" % (name_value,))
            # Handle case of a control-name with no equal sign
            if keep_blank_values:
                nv.append('')
            else:
                continue

        if len(nv[1]) or keep_blank_values:
            name = nv[0].replace('+', ' ')
            name = unquote(name, encoding)
            value = nv[1].replace('+', ' ')
            value = unquote(value, encoding)
            r.append((name, value))

    return r


def unquote(string, encoding='utf-8'):
    """unquote('abc%20def') -> 'abc def'.

    string may also be an UTF-8 encoded byte-string.

    """
    if not string:
        return ''

    if isinstance(string, str):
        string = string.encode('utf-8')

    bits = string.split(b'%')
    if len(bits) == 1:
        return string.decode(encoding)

    res = [bits[0]]
    append = res.append

    for item in bits[1:]:
        try:
            append(bytes([int(item[:2], 16)]))
            append(item[2:])
        except KeyError:
            append(b'%')
            append(item)

    return b''.join(res).decode(encoding)


if __name__ == '__main__':
    #from urlparse import parse_qsl
    url = 'power=10&time=0.7&long+name+with+spaces=value%20with%20%C3%BCnicode'
    for name, val in parse_qsl(url):
        print("%s: %s" % (name, val))