IDLE 控制台中 Flask 应用程序的导入错误

Question

I want to import a Flask object into IDLE so that I can experiment and explore.

I am able to launch an interactive command line session successfully by typing python from the project directory.

Python 3.7.5 (default, Nov 18 2019, 00:27:11)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from app import app
>>> dir(app)
['Flask', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', 
'__package__', '__spec__', 'app', 'create_app', 'current_app', 'index', 'make_response', 'randint']
>>> exit()

But I want to use IDLE for this exploration.
So I added my project path to sys.path in IDLE. When I try to import using from app import app , I get the error AttributeError: module 'config' has no attribute 'settings .

The code sample:

from flask import Flask

def create_app():
    app = Flask(__name__,instance_relative_config=True)

    app.config.from_object('config.settings')
    app.config.from_pyfile('settings.py',silent=True)

    return app

Project structure:

project_dir/
   ├── app/
   │   ├── app.py
   ├── config/
   │   │                                                                                                                                                                                
   │   └── settings.py                                                                                                                                                                                               
   └── instance/                                                                                                                                                                                                          
       └── settings.py 

Why is IDLE unable to find the settings.py module in the config directory?

NOTE: When I remove the line app.config.from_object('config.settings') , the import succeeds.

Answer 1

IDLE only finds files when you use the IDLE open command to edit a file. When you ask IDLE to execute your code, it calls compile() and passes the result to the executing python.

app.config.from_object('config.settings') fails for the reason given in the error message: the config object has no attribute settings . Adding import config.settings may fix this. I cannot be sure because your project structure diagram is ambiguous. It shows config as both a top-level directory, parallel to app and instance and as a subdirectory of app .