Use of Params in pyspak

Question

In this example, I am trying to use overrides as a Params object and I want it to be used as a list of strings.

But I am not able to assign its value using the below code.

class _AB(Params):

    overrides = Param(Params._dummy(), "overrides", "Parameters for environment setup", typeConverter=TypeConverters.toListString)
    
    def __init__(self, *args):
        super().__init__(*args)
        self._setDefault(overrides=None)
        

class A(_AB):
  @keyword_only
  def __init__(self, overrides):
    super().__init__()
    kwargs = self._input_kwargs
    self.setParams(**kwargs)

  @keyword_only
  def setParams(self, overrides: List[str]):
      kwargs = self._input_kwargs
      print(kwargs)
      return self._set(**kwargs)

  def c(self):
    print(self.overrides.__dict__['typeConverter'].__dict__)
    for i in self.overrides:
       print(i)

a = A(overrides=["dsfs", "Sdf"])
a.c()

It gives me a blank dictionary when I print it inside function c.
It gives me an error:

TypeError: 'Param' object is not iterable

I guess it's happening because it's not able to assign some value to overrides variable.

Answer 1

Param object required to access from a get function else it will report some error. I should access self.overrides from a get function.

E.g:

class _AB(Params):

    overrides = Param(Params._dummy(), "overrides", "Overrides parameters for environment setup", typeConverter=TypeConverters.toListString)
    
    def __init__(self, *args):
        super().__init__(*args)
        self._setDefault(overrides=None)
    def getoverrides(self):
        return self.getOrDefault(self.overrides)

class A(_AB):
  @keyword_only
  def __init__(self, overrides):
    super().__init__()
    kwargs = self._input_kwargs
    self.setParams(**kwargs)

  @keyword_only
  def setParams(self, overrides: List[str]):
      kwargs = self._input_kwargs
      return self._set(**kwargs)

  def c(self):
    overrides = self.getoverrides()
    for i in overrides:
       print(i)

a = A(overrides=["Alpha", "Beta"])
a.c()

It gives:

Alpha
Beta