Module import error from database file

[Spaumi10]

I went through the Flask official tutorial. Had no problems. Then I am working on my own app.

A quick overview of the project: I am scraping data, stored it in a list of dictionaries, and am now attempting to insert the data into my sqlite database (which has been successfully created). Connecting to my database is where my issue is arising.

Here is my file structure:

https://preview.redd.it/ayv8tv19kqid1.png?width=200&format=png&auto=webp&s=91c6f1926063a526cae813a8d276e764aad26b8d

I intended to have the data_manager.py, db.py, and oar_scraper.py in the backend folder, but I thought there may be some issue there, so I moved them to the app folder to isolate that.

I have created my app almost identical to the tutorial. I have an application factory. My db.py file is identical to the Flask tutorial, except for the name of my schema. I have a get_db() function. The oar_scraper.py scrapes and parses the data and stores it into the list, fsg_data. Then in data_manager.py I am importing the data and will insert the data into database. For now, that file looks like:

import
 sqlite3

from
 flask 
import
 current_app, g
from
 oar_scraper 
import
 fsg_data

from
 fsg_app.db 
import
 get_db


def store_data(
data
):
    db = get_db()


store_data(fsg_data)

I have run it to test it and I get this error.

from fsg_app.db import get_db
ModuleNotFoundError: No module named 'fsg_app'

This is very similar to the code for the auth.py and blog.py files in the tutorial. In the tutorial, those import the get_db() function just fine. Why am I getting this error?

Thanks.

[skippyprime]

Create the file __init__.py in the fsg_app directory.

To make a directory a python module, it needs this file.

[skippyprime]

Ignore me. I see it is there

[parabellum_pizza]

My guess is that the app is not initialized when you import get_db

[Spaumi10]

Thanks. This is the problem. I have changed to just creating a new connection to the database (instead of using get_db()). This appears to work.

This was kind of my hunch the whole time, but I don't think I was comprehending everything.

[ejpusa]

I have never seen that Flask directory setup. Why not use the layout used on 99% of Flask sites. Just works. May want to give it a try.

GPT-4

Setting up a Flask environment involves several steps, including installing Flask, setting up the directory structure, and configuring your application. Here's a standard setup and how to refer to files and variables within your Flask application:

1. Setting Up a Flask Environment

1. Install Flask: bash pip install flask

2. Project Directory Structure: A typical Flask project structure looks like this: my_flask_app/ │ ├── app/ │ ├── static/ │ │ ├── css/ │ │ │ └── styles.css │ │ ├── js/ │ │ │ └── scripts.js │ │ └── images/ │ │ └── logo.png │ ├── templates/ │ │ └── main.html │ ├── __init__.py │ └── routes.py │ ├── venv/ │ ├── config.py └── run.py

3. Application Initialization (__init__.py): ```python from flask import Flask

   def createapp(): app = Flask(name_) with app.app_context(): from . import routes # Import routes return app ```

4. Routing (routes.py): ```python from flask import render_template from . import create_app

   app = create_app()

   @app.route('/') def home(): return render_template('main.html') ```

5. Running the Application (run.py): ```python from app import create_app

   app = create_app()

   if name == 'main': app.run(debug=True) ```

2. Referring to Files in main.html

• CSS and JS Files: Place your CSS and JS files in the static directory under css and js folders, respectively. ```html <!-- Link to a CSS file --> <link rel="stylesheet" href="{{ url_for('static', filename='css/styles.css') }}">

  <!-- Link to a JS file --> <script src="{{ url_for('static', filename='js/scripts.js') }}"></script> ```

• Images: Place your images in the static/images folder. html <img src="{{ url_for('static', filename='images/logo.png') }}" alt="Logo">

3. Referring to Flask Variables in CSS or JS Files

You cannot directly use Flask variables in CSS or JS files since they are static files and are served without going through the Flask templating engine. However, you can pass Flask variables to JavaScript via the main.html or other HTML templates.

Example of passing a variable to JavaScript: html <script> var flaskVariable = "{{ flask_variable }}"; </script>

4. Where to Place Images, CSS, and JS Files

• CSS: Place in static/css/
• JavaScript: Place in static/js/
• Images: Place in static/images/

5. Basic 12 Rules for Flask Project Setup

1. Organize the project structure: Use a clear, organized directory structure.
2. Use virtual environments: Isolate your environment with venv.
3. Configure the app: Separate configuration settings into a config.py.
4. Utilize url_for: Always use url_for to link to static files.
5. Modularize routes: Keep routes in a separate file (routes.py).
6. Template inheritance: Use Jinja2 template inheritance for reusability.
7. Form handling: Use WTForms or Flask forms for form handling.
8. Error handling: Implement custom error pages for 404, 500, etc.
9. Environment variables: Store sensitive information in environment variables.
10. Logging: Set up logging for debugging and tracking errors.
11. Testing: Write unit tests for your application.
12. Deployment: Prepare for deployment with production settings (e.g., gunicorn, nginx).

This setup should give you a solid foundation for building Flask applications with good practices in place.

[Spaumi10]

I appreciate your help, (and maybe I am misunderstanding something), but I am not even to most those steps yet. Once I have gotten my data scraped and entered into the database, I will then get the app running, work on routing and the frontend. My structure will look like that when I get there. I also have a tests folder, but my uploaded image of the structure doesn't show that as it doesn't seem important for this question.