知识点：

        - 给你一个路径 “settings.Foo”，可以找到类并获取去其中的大写的静态字段。

            settings.py

                class Foo:

                    DEBUG = True

                    TEST = True

            xx.py

                import importlib

                path = "settings.Foo"

                p,c = path.rsplit('.',maxsplit=1)

                m = importlib.import_module(p)

                cls = getattr(m,c)

                # 如果找到这个类？

                for key in dir(cls):

                    if key.isupper():

                        print(key,getattr(cls,key))

from flask import Flask, render_template, request, redirect, session

app = Flask(__name__)

print(app.config)

# app.config["DEBUG"] = True

'''

<Config {'ENV': 'development', 'DEBUG': False, 'TESTING': False, 'PROPAGATE_EXCEPTIONS': None, 'PRESERVE_CONTEXT_ON_EXCEPTION': None,

'SECRET_KEY': None, 'PERMANENT_SESSION_LIFETIME': datetime.timedelta(31), 'USE_X_SENDFILE': False, 'SERVER_NAME': None,

'APPLICATION_ROOT': '/', 'SESSION_COOKIE_NAME': 'session', 'SESSION_COOKIE_DOMAIN': None, 'SESSION_COOKIE_PATH': None,

'SESSION_COOKIE_HTTPONLY': True, 'SESSION_COOKIE_SECURE': False, 'SESSION_COOKIE_SAMESITE': None,

'SESSION_REFRESH_EACH_REQUEST': True, 'MAX_CONTENT_LENGTH': None,

'SEND_FILE_MAX_AGE_DEFAULT': datetime.timedelta(0, 43200), 'TRAP_BAD_REQUEST_ERRORS': None,

'TRAP_HTTP_EXCEPTIONS': False, 'EXPLAIN_TEMPLATE_LOADING': False, 'PREFERRED_URL_SCHEME': 'http', 'JSON_AS_ASCII': True,

'JSON_SORT_KEYS': True, 'JSONIFY_PRETTYPRINT_REGULAR': False, 'JSONIFY_MIMETYPE': 'application/json',

'TEMPLATES_AUTO_RELOAD': None, 'MAX_COOKIE_SIZE': 4093}>

'''

app.config.from_object("settings.ProductionConfig")

if __name__ == '__main__':

    app.run()

#!/usr/bin/env python3

# -*- coding:utf-8 -*-

# __Author__:TQTL911

# Version:python3.6.6

# Time:2018/8/30 22:29

class Config(object):

    DEBUG = False

    TESTING = False

    DATABASE_URI = 'sqlite://:memory:'

class ProductionConfig(Config):

    DATABASE_URI = 'mysql://user@localhost/foo'

class DevelopmentConfig(Config):

    DEBUG = True

class TestingConfig(Config):

    TESTING = True

# class Base(object):

#     """

#     创建一个父类;

#     """

#     xx = 123

#

#

# class Pro(Base):

#     """

#     生产环境;

#     """

#     DEBUT = True

#

#

# class Dev(Base):

#     """

#     开发环境;

#     """

#     DEBUG = True