I am working with a large Python class with dozens of "business logic" methods and a few helper methods. There is some funny code at the end that is being used to run all "calc_metric_*" methods.

Something that looks a bit like:

class CalculateMetrics:
    ...

    def calc_metric_x1(self):
        ...

    def calc_metric_x2(self):
        ...

    def calc_metric_x3(self):
        ...

    def calc_metric_x4(self):
        ...
    
    ...

    def calc_metric_x50(self):
        ...

    def run_all(self):
       method_list = [m for m in dir(self) 
                      if callable(getattr(self, m)) 
                      and m.startswith('calc_metric_')]

       for m in method_list:
           # Call each method
           getattr(self, m)()

The use of getattr referencing the method's name doesn't seem optimal to me. Is there a better way to achieve this in Python?

CodePudding user response：

You could use a decorator function that collects them like this:

def calc_metric(func):
    if func not in calc_metric.calc_metric_funcs:
        calc_metric.calc_metric_funcs.append(func)
    return func


calc_metric.calc_metric_funcs = []

Then you need to decorate all the desired functions with @calc_metric:

    @calc_metric
    def calc_metric_x1(self):
        
        ...

    @calc_metric
    def calc_metric_x2(self):
        ...

    ...

    @calc_metric
    def calc_metric_x50(self):
        ...

And you run_all() function will be like this:

    def run_all(self):
        for f in calc_metric.calc_metric_funcs:
            f(self)

Note that the calc_metric function must be declared outside of the CalculateMetrics class.