knext parameter as dictionary object

Dear KNIMErs and developers,

I am exploring the new python based KNIME extension. I need to generate the fields (parameters) in node configuration dialogue from a JSON file. I’m first parsing the JSON attribute and its values into a python list and then based on type of value, generate corresponding knext.parameter. This is how it is done in my code example below.

1. Parse the JSON attribute and value as lists.

import json
    keys = []
    values = []
    with open('config_json.json', "r") as read_file:
        data = json.load(read_file)

     for key, value in data.items():
        keys.append(key)
        values.append(value)

2. Depending upon the attribute value type generate knext parameter. e.g.

import knime.extension as knext

       if isinstance(value, str):
                aa = knext.StringParameter(key[idx], key[idx] ,value)
       if isinstance(value, float):
                bb = knext.DoubleParameter(key[idx], key[idx] ,value)

This works fine and configuration dialogue is rendered with correct parameters. However, Since content of JSON file can vary I have no way of knowing how many parameter object I would need. I thought of using dictionary to solve this issue. Something like below.

import knime.extension as knext

variable_dict = {}
    for k, v in enumerate(value):
        if isinstance(v, str):
            variable_dict[k] = knext.StringParameter(k, k ,v)
         if isinstance(v, float):
                variable_dict[k]  = knext.DoubleParameter(k, k,v)

But this doesn’t work and parameters fields are not rendered in configuration dialogue.

I’m looking for suggestion, if this is something feasible or how to do it?

Thanks.

Bilal

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