Python Flask multiple call to create_app()

Question

I am trying to develop an API using the Flask micro web platform but I have hit an issue when I noticed that the same object is being created multiple times as multiple log entries are getting posted and also unnecessary memory usage is occurring. I am running Python 3.7 on 64 bit Windows 10 desktop computer.

I have condensed this down to the simplest working example that still exhibits the issue:

from flask import Flask

class de(object):
    def __init__(self):
        print(f'__init__ : {self}')

    def __del__(self):
        print(f'__del__ : {self}')

def create_app(test_config=None):
    app = Flask(__name__)
    det = de()
    return app

The output running flask run -p 2094 is:

 * Serving Flask app "APP-Account-Api/src" (lazy loading)
 * Environment: development
 * Debug mode: on
 * Restarting with stat
 * Debugger is active!
 * Debugger PIN: 201-506-894
 * Running on http://127.0.0.1:2094/ (Press CTRL+C to quit)
__init__ : <src.de object at 0x000001AE906C4A90>
__del__ : <src.de object at 0x000001AE906C4A90>
__init__ : <src.de object at 0x0000023488C73C50>
__del__ : <src.de object at 0x0000023488C73C50>

As you can see I only create the test class once but the log is showing two sets of creation and destruction.

Python Flask multiple call to create_app()

0 Answers0