Flask API Development Skill

Flask API Development

Overview
When to Use
Quick Start
Reference Guides
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 | Flask Application Setup | | Database Models with SQLAlchemy | Database Models with SQLAlchemy | | Authentication and JWT | Authentication and JWT | | Blueprints for Modular API Design | Blueprints for Modular API Design | | Request Validation | Request Validation | | Application Factory and Configuration | 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

Agent Skills: Flask API Development

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