Dynamic introduction package python

Preparation of a web frame in real python tutorial in the teacher Liaoxue Feng, see ( https://www.liaoxuefeng.com/wiki/1016959663602400/1018490695712544 ), which has a function add_routes, code is as follows:

def add_routes(app, module_name):
    n = module_name.rfind('.')
    if n == (-1):
        mod = __import__(module_name, globals(), locals())
    else:
        name = module_name[n+1:]
        mod = getattr(__import__(module_name[:n], globals(), locals(), [name]), name)
    for attr in dir(mod):
        if attr.startswith('_'):
            continue
        fn = getattr(mod, attr)
        if callable(fn):
            method = getattr(fn, '__method__', None)
            path = getattr(fn, '__route__', None)
            if method and path:
                add_route(app, fn)

On the basis of Liao Xuefeng teacher code, I made some changes.

Import_module using a relatively simple way to view dynamic import function (control) packet, and then using a recursive method to all the modules walk_packages dynamic introduced into the package.

import importlib
import pkgutil


base = importlib.import_module('app.controller')

for loader, module_name, is_pkg in  pkgutil.walk_packages(base.__path__, f'{base.__name__}.'):

    try:
        sub_module = __import__(module_name, fromlist=['get_submodule'])
    except ImportError as e:
        raise e

# 后面代码略