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Deserialize config to python object

Challenges

writing a custom class takes time
using a dict is too primitive, and has no autocomplete.

sample config, can be loaded with Python config loader utils-

my_settings:

  - key1: value1
  - key2: value2
  - key3: value3


class MySettings:
    def __init__(self):
        self.key1 = value1
        self.key2 = value2
        self.key3 = value3

But ideally the class can be dynamically create, passing the values to __init__.
class MySettings:
    def __init__(self, key1=None, key2=None, key3=None):
        # we use `or` since mutatible values (e.g. strings) 
        # can't be used as kwarg default values
        self.key1 = key1 or value1
        self.key2 = key2 or value2
        self.key3 = key3 or value3

With *args & **kwargs, attribute values can be dynamically loaded with setattr, but then we loose IDE auto complete.

Another option could be to create the class with empty args and let the user fill them in after instance creation.

When the class is only used in a config loader, it can make sense to pass the config as a single value instead.

class MySettings:
    def __init__(self, config_dict):
        ...

other

But now every time the config is updated, the python class needs updating.

other

alternatives?

  • investigate dataclass
  • typed dict

see

deserialize

Python
config