helpers.py

import sqlite3
from flask import redirect, session
from functools import wraps

# Function to redirect user to login page if not logged in
def login_required(f):
    """
    Decorate routes to require login.

    http://flask.pocoo.org/docs/0.12/patterns/viewdecorators/
    """
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if session.get("user_id") is None:
            return redirect("/login")
        return f(*args, **kwargs)
    return decorated_function

# Function to get database connection
def get_db_connection(db_name):
    conn = sqlite3.connect(db_name)
    conn.row_factory = sqlite3.Row  # to access columns by name
    return conn

# Function to check allowed file extensions
def allowed_file(filename, ALLOWED_EXTENSIONS):
    return '.' in filename and filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS