__init__.py

from flask import Flask
from flask_login import LoginManager
from flask_cors import CORS
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
import os

"""
These object can be used throughout project.
1.) Objects from this file can be included in many blueprints
2.) Isolating these object definitions avoids duplication and circular dependencies
"""

# Setup of key Flask object (app)
app = Flask(__name__)

# Initialize Flask-Login object
login_manager = LoginManager()
login_manager.init_app(app)

# Allowed servers for cross-origin resource sharing (CORS), these are GitHub Pages and localhost for GitHub Pages testing
cors = CORS(app, supports_credentials=True, origins=['http://localhost:4100', 'http://127.0.0.1:4100', 'https://nighthawkcoders.github.io'])

# Secret key for session handling and CSRF protection
SECRET_KEY = os.environ.get('SECRET_KEY') or 'SECRET_KEY'
SESSION_COOKIE_NAME = os.environ.get('SESSION_COOKIE_NAME') or 'sess_python_flask'
JWT_TOKEN_NAME = os.environ.get('JWT_TOKEN_NAME') or 'jwt_python_flask'
app.config['SECRET_KEY'] = SECRET_KEY
app.config['SESSION_COOKIE_NAME'] = SESSION_COOKIE_NAME 
app.config['JWT_TOKEN_NAME'] = JWT_TOKEN_NAME 

# Setup SQLAlchemy object and properties for the database (db)
# Local SQLite database within the instance folder
dbURI = 'sqlite:///volumes/sqlite.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['SQLALCHEMY_DATABASE_URI'] = dbURI
db = SQLAlchemy()
Migrate(app, db)

# Images storage settings and location
app.config['MAX_CONTENT_LENGTH'] = 5 * 1024 * 1024  # maximum size of uploaded content
app.config['UPLOAD_EXTENSIONS'] = ['.jpg', '.png', '.gif']  # supported file types
app.config['UPLOAD_FOLDER'] = os.path.join(app.instance_path, 'uploads')
os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)