Flask

Key Features

• Lightweight: Minimal core with extensions for additional functionality
• Flexible: No rigid project structure or dependencies
• WSGI Compliant: Compatible with various web servers
• Jinja2 Templates: Powerful templating engine
• Built-in Development Server: Easy testing and debugging
• RESTful Request Dispatching: Clean URL routing

Basic Flask Application

                        
from flask import Flask, render_template, request, jsonify

app = Flask(__name__)

@app.route('/')
def home():
    return render_template('index')

@app.route('/api/users', methods=['GET', 'POST'])
def users():
    if request.method == 'POST':
        user_data = request.get_json()
        # Process user data
        return jsonify({'message': 'User created', 'user': user_data})
    else:
        # Return list of users
        users = [{'id': 1, 'name': 'John'}, {'id': 2, 'name': 'Jane'}]
        return jsonify(users)

@app.route('/user/<int:user_id>')
def user_profile(user_id):
    # Fetch user by ID
    user = {'id': user_id, 'name': 'User ' + str(user_id)}
    return render_template('profile', user=user)

if __name__ == '__main__':
    app.run(debug=True)
                        
                    

Flask with Database (SQLAlchemy)

                        
from flask import Flask
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///app.db'
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)
    email = db.Column(db.String(120), unique=True, nullable=False)

    def __repr__(self):
        return f'<User {self.username}>'

@app.route('/create-user')
def create_user():
    user = User(username='john_doe', email='john@example.com')
    db.session.add(user)
    db.session.commit()
    return 'User created!'

# Create tables
with app.app_context():
    db.create_all()
                        
                    

Career Impact

Learning Path

1. Master Python fundamentals and object-oriented programming
2. Learn HTTP protocols and web development concepts
3. Understand Flask routing and request handling
4. Practice with Jinja2 templating and forms
5. Integrate databases using SQLAlchemy
6. Implement authentication and security best practices
7. Deploy Flask applications to production