/flask-api-development

name: flask-api-development
description: >
  Develop lightweight Flask APIs with routing, blueprints, database integration,
  authentication, and request/response handling. Use when building RESTful APIs,
  microservices, or lightweight web services with Flask.

Flask API Development

Table of Contents

• [Overview](#overview)
• [When to Use](#when-to-use)
• [Quick Start](#quick-start)
• [Reference Guides](#reference-guides)
• [Best Practices](#best-practices)

Overview

Create efficient Flask APIs with blueprints for modular organization, SQLAlchemy for ORM, JWT authentication, comprehensive error handling, and proper request validation following REST principles.

When to Use

• Building RESTful APIs with Flask
• Creating microservices with minimal overhead
• Implementing lightweight authentication systems
• Designing API endpoints with proper validation
• Integrating with relational databases
• Building request/response handling systems

Quick Start

Minimal working example:

# app.py
from flask import Flask, request, jsonify
from flask_cors import CORS
from flask_sqlalchemy import SQLAlchemy
from flask_jwt_extended import JWTManager
import os

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = os.getenv('DATABASE_URL', 'sqlite:///app.db')
app.config['JWT_SECRET_KEY'] = os.getenv('JWT_SECRET_KEY', 'dev-secret')
app.config['JSON_SORT_KEYS'] = False

db = SQLAlchemy(app)
jwt = JWTManager(app)
CORS(app)

# Request ID middleware
@app.before_request
def assign_request_id():
    import uuid
    request.request_id = str(uuid.uuid4())

# Error handlers
@app.errorhandler(400)
def bad_request(error):
// ... (see reference guides for full implementation)

Reference Guides

Detailed implementations in the `references/` directory:

| Guide | Contents | |---|---| | [Flask Application Setup](references/flask-application-setup.md) | Flask Application Setup | | [Database Models with SQLAlchemy](references/database-models-with-sqlalchemy.md) | Database Models with SQLAlchemy | | [Authentication and JWT](references/authentication-and-jwt.md) | Authentication and JWT | | [Blueprints for Modular API Design](references/blueprints-for-modular-api-design.md) | Blueprints for Modular API Design | | [Request Validation](references/request-validation.md) | Request Validation | | [Application Factory and Configuration](references/application-factory-and-configuration.md) | Application Factory and Configuration |

Best Practices

✅ DO

• Use blueprints for modular organization
• Implement proper authentication with JWT
• Validate all user input
• Use SQLAlchemy ORM for database operations
• Implement comprehensive error handling
• Use pagination for collection endpoints
• Log errors and important events
• Return appropriate HTTP status codes
• Implement CORS properly
• Use environment variables for configuration

❌ DON'T

• Store secrets in code
• Use global variables for shared state
• Ignore database transactions
• Trust user input without validation
• Return stack traces in production
• Use mutable default arguments
• Forget to handle database connection errors
• Implement authentication in route handlers