Question

I’m a python noob and I’m trying to solve my problems the ‘pythonic’ way. I have a class, who’s __init__ method takes 6 parameters. I need to validate each param and throw/raise an Exception if any fails to validate.

Is this the right way?

class DefinitionRunner:
    def __init__(self, canvasSize, flightId, domain, definitionPath, harPath):
        self.canvasSize = canvasSize
        self.flightId   = flightId
        self.domain     = domain
        self.harPath    = harPath
        self.definitionPath = definitionPath

        ... bunch of validation checks...
        ... if fails, raise ValueError ...

Answer 1

Broadly speaking, that looks like the way you’d do it. Though strictly speaking, you might as well do validation before rather than after assignment, especially if assignment could potentially be time or resource intensive. Also, style convention says not to align assignment blocks like you are.