Randomly Implementing Flask Extensions in a Python Function

This code defines a Python function within a Flask application that randomly selects a third-party Flask extension and implements its functionality. The code utilizes multiple Flask extensions such as Flask-SQLAlchemy, Flask-Migrate, Flask-Mail, Flask-Login, Flask-WTF, and Flask-RESTful.

Technology Stack : Flask, Flask-SQLAlchemy, Flask-Migrate, Flask-Mail, Flask-Login, Flask-WTF, Flask-RESTful

Code Type : Flask application with a custom function

Code Difficulty : Intermediate

                
                    
from flask import Flask, jsonify, request
import random
from werkzeug.exceptions import HTTPException

app = Flask(__name__)

def generate_random_function():
    # List of possible Flask extensions
    extensions = ['Flask-SQLAlchemy', 'Flask-Migrate', 'Flask-Mail', 'Flask-Login', 'Flask-WTF', 'Flask-RESTful']
    
    # Randomly select an extension to use
    selected_extension = random.choice(extensions)
    
    # Define the function based on the selected extension
    def random_function(request_data):
        if selected_extension == 'Flask-SQLAlchemy':
            # Function using Flask-SQLAlchemy to create a new user
            from flask_sqlalchemy import SQLAlchemy
            db = SQLAlchemy(app)
            
            class User(db.Model):
                id = db.Column(db.Integer, primary_key=True)
                username = db.Column(db.String(80), unique=True, nullable=False)
            
            new_user = User(username=request_data['username'])
            db.session.add(new_user)
            db.session.commit()
            return jsonify({'message': 'User created successfully'}), 201
        elif selected_extension == 'Flask-Migrate':
            # Function using Flask-Migrate to create a database migration
            from flask_migrate import Migrate
            migrate = Migrate(app, db)
            
            # Generate a migration script
            migrate.init_app(app, db)
            migrate.upgrade()
            return jsonify({'message': 'Migration created successfully'}), 200
        elif selected_extension == 'Flask-Mail':
            # Function using Flask-Mail to send an email
            from flask_mail import Mail, Message
            mail = Mail(app)
            
            msg = Message('Hello', recipients=['recipient@example.com'])
            msg.body = 'Hello Flask-Mail'
            mail.send(msg)
            return jsonify({'message': 'Email sent successfully'}), 200
        elif selected_extension == 'Flask-Login':
            # Function using Flask-Login to log in a user
            from flask_login import LoginManager, UserMixin, login_user, logout_user
            
            login_manager = LoginManager()
            login_manager.init_app(app)
            
            class User(UserMixin, db.Model):
                id = db.Column(db.Integer, primary_key=True)
                username = db.Column(db.String(80), unique=True, nullable=False)
            
            @login_manager.user_loader
            def load_user(user_id):
                return User.query.get(int(user_id))
            
            user = User(username=request_data['username'])
            login_user(user)
            return jsonify({'message': 'User logged in successfully'}), 200
        elif selected_extension == 'Flask-WTF':
            # Function using Flask-WTF to validate a form
            from flask_wtf import FlaskForm
            from wtforms import StringField, PasswordField
            from wtforms.validators import InputRequired, Length
            
            class LoginForm(FlaskForm):
                username = StringField('Username', validators=[InputRequired(), Length(min=4, max=25)])
                password = PasswordField('Password', validators=[InputRequired(), Length(min=4, max=25)])
            
            form = LoginForm(request_data)
            if form.validate():
                return jsonify({'message': 'Form is valid'}), 200
            else:
                return jsonify({'errors': form.errors}), 400
        elif selected_extension == 'Flask-RESTful':
            # Function using Flask-RESTful to create a resource
            from flask_restful import Resource, Api, reqparse
            
            api = Api(app)
            
            parser = reqparse.RequestParser()
            parser.add_argument('name', required=True, help='The name cannot be blank')
            parser.add_argument('age', type=int, required=True, help='The age cannot be blank')
            
            class PersonResource(Resource):
                def post(self):
                    args = parser.parse_args()
                    return {'message': f'Person {args["name"]} added with age {args["age"]}'}, 201
            
            api.add_resource(PersonResource, '/person')
            return jsonify({'message': 'Resource created successfully'}), 200

# Example usage:
# To use the function, you can pass a request data as a dictionary
# request_data = {'username': 'new_user', 'password': 'password123'}
# response = random_function(request_data)
# print(response)

# Flask app setup for running the function
if __name__ == '__main__':
    app.run(debug=True)