Junior in team asked me if they don't want to see exponential notation in json, how to do in python?

json-float-as-string.py

import json
import re

class CustomJSONEncoder(json.JSONEncoder):
    def encode_float(self, obj):
        if isinstance(obj, float):
            return format(obj, "f").rstrip('0').rstrip('.')
        return super().encode(obj)

    def encodeObj(self, obj):
        if isinstance(obj, float):
            return self.encode_float(obj)
        if isinstance(obj, dict):
            return {k: self.encodeObj(v) for k, v in obj.items()}
        if isinstance(obj, list):
            return [self.encodeObj(v) for v in obj]
        return obj

    def encode(self, o):
        return super().encode(self.encodeObj(o))


def decode_float(obj):
    if isinstance(obj, dict):
        return {k: decode_float(v) for k, v in obj.items()}
    elif isinstance(obj, list):
        return [decode_float(i) for i in obj]
    elif isinstance(obj, str):
        try:
            # Regular expression to check if the string contains only digits and at most one full stop
            if re.fullmatch(r'[-]?\d*\.?\d+', obj):
                return float(obj)
        except ValueError:
            pass
    return obj

data = {
    "name": "Sample",
    "value": 0.000064,
    "meta": {
        "details": [1.23, 0.000064, 7.89]
    }
}

# Encoding
json_str = json.dumps(data, cls=CustomJSONEncoder)
print(json_str)

# Decoding
decoded_data = json.loads(json_str, object_hook=decode_float)
print(decoded_data)

# ❯ python3 test.py
# {"name": "Sample", "value": "0.000064", "meta": {"details": ["1.23", "0.000064", "7.89"]}}
# {'name': 'Sample', 'value': 6.4e-05, 'meta': {'details': [1.23, 6.4e-05, 7.89]}}