Flask-SQLAlchemy import/context issue

Michael Zippo

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I want to structure my Flask app something like:

./site.py
./apps/members/__init__.py
./apps/members/models.py

apps.members is a Flask Blueprint.

Now, in order to create the model classes I need to have a hold of the app, something like:

# apps.members.models
from flask import current_app
from flaskext.sqlalchemy import SQLAlchemy

db = SQLAlchemy(current_app)

class Member(db.Model):
    # fields here
    pass

But if I try and import that model into my Blueprint app, I get the dreaded RuntimeError: working outside of request context. How can I get a hold of my app correctly here? Relative imports might work but they"re pretty ugly and have their own context issues, e.g:

from ...site import app

# ValueError: Attempted relative import beyond toplevel package

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Flask-SQLAlchemy import/context issue del: Questions

__del__

How can I make a time delay in Python?

5 answers

I would like to know how to put a time delay in a Python script.

2973

Answer #1

import time
time.sleep(5)   # Delays for 5 seconds. You can also use a float value.

Here is another example where something is run approximately once a minute:

import time
while True:
    print("This prints once a minute.")
    time.sleep(60) # Delay for 1 minute (60 seconds).

2973

Answer #2

You can use the sleep() function in the time module. It can take a float argument for sub-second resolution.

from time import sleep
sleep(0.1) # Time in seconds

Flask-SQLAlchemy import/context issue del: Questions

__del__

How to delete a file or folder in Python?

5 answers

How do I delete a file or folder in Python?

2639

Answer #1

os.remove() removes a file.
os.rmdir() removes an empty directory.
shutil.rmtree() deletes a directory and all its contents.

Path objects from the Python 3.4+ pathlib module also expose these instance methods:

pathlib.Path.unlink() removes a file or symbolic link.
pathlib.Path.rmdir() removes an empty directory.

We hope this article has helped you to resolve the problem. Apart from Flask-SQLAlchemy import/context issue, check other __del__-related topics.

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Cornwall Chamberlet

Vigrinia | 2023-03-24

Maybe there are another answers? What Flask-SQLAlchemy import/context issue exactly means?. Will get back tomorrow with feedback

Anna Zelotti

Shanghai | 2023-03-24

re Python module is always a bit confusing 😭 Flask-SQLAlchemy import/context issue is not the only problem I encountered. Checked yesterday, it works!

Boris Lehnman

Warsaw | 2023-03-24

Simply put and clear. Thank you for sharing. Flask-SQLAlchemy import/context issue and other issues with StackOverflow was always my weak point 😁. Checked yesterday, it works!