flask-expert

Flask Expert

Expert guidance for Flask web development, building REST APIs, using extensions, and production deployment.

Core Concepts

Flask Fundamentals

• Routing and views
• Request/response handling
• Templates with Jinja2
• Blueprints for modularity
• Application factory pattern
• Configuration management

Flask Extensions

• Flask-SQLAlchemy (ORM)
• Flask-Migrate (database migrations)
• Flask-Login (authentication)
• Flask-RESTful (REST APIs)
• Flask-JWT-Extended (JWT tokens)
• Flask-CORS (CORS handling)
• Flask-Limiter (rate limiting)

Best Practices

• Application structure
• Error handling
• Testing
• Security
• Production deployment

Basic Flask Application

from flask import Flask, request, jsonify, render_template
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from werkzeug.security import generate_password_hash, check_password_hash
from datetime import datetime

# Application factory
def create_app(config_name='development'):
    app = Flask(__name__)
    app.config.from_object(config[config_name])

    # Initialize extensions
    db.init_app(app)
    migrate.init_app(app, db)

    # Register blueprints
    from .api import api_bp
    app.register_blueprint(api_bp, url_prefix='/api')

    from .auth import auth_bp
    app.register_blueprint(auth_bp, url_prefix='/auth')

    return app

# Database setup
db = SQLAlchemy()
migrate = Migrate()

# Models
class User(db.Model):
    __tablename__ = 'users'

    id = db.Column(db.Integer, primary_key=True)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(255), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)

    posts = db.relationship('Post', backref='author', lazy='dynamic')

    def set_password(self, password):
        self.password_hash = generate_password_hash(password)

    def check_password(self, password):
        return check_password_hash(self.password_hash, password)

    def to_dict(self):
        return {
            'id': self.id,
            'email': self.email,
            'created_at': self.created_at.isoformat()
        }

class Post(db.Model):
    __tablename__ = 'posts'

    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(200), nullable=False)
    content = db.Column(db.Text, nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)

    def to_dict(self):
        return {
            'id': self.id,
            'title': self.title,
            'content': self.content,
            'author': self.author.to_dict(),
            'created_at': self.created_at.isoformat()
        }