[Nuke] Listing all user defined knobs in given node

get_user_knobs.py

import nuke
import re


def list_user_knobs(node):
    """Get user defined knobs

    Args:
        node (nuke.Node): Nuke node object

    Returns:
        list: A list of nuke.Knob object

    """
    user_knobs = list()

    pattern = ("(?<=addUserKnob {)"
               "([0-9]*) (\\S*)"  # Matching knob type and knob name
               "(?=[ |}])")
    tcl_script = node.writeKnobs(nuke.WRITE_USER_KNOB_DEFS)
    result = re.search(pattern, tcl_script)

    if result:
        first_user_knob = result.group(2)
        # Collect user knobs from the end of the knob list
        for knob in reversed(node.allKnobs()):
            user_knobs.insert(0, knob)
            if knob.name() == first_user_knob:
                break

    return user_knobs