Ett exempel: ett enkelt TODO-api

todo.py

from flask import Flask, jsonify, request
import sqlite3

app = Flask(__name__)

def init_db():
    with sqlite3.connect('todo.db') as conn:
        cursor = conn.cursor()
        cursor.execute('''CREATE TABLE IF NOT EXISTS todos (
                            id INTEGER PRIMARY KEY AUTOINCREMENT,
                            title TEXT NOT NULL,
                            completed BOOLEAN NOT NULL CHECK (completed IN (0, 1))
                          )''')
        conn.commit()

init_db()

@app.route('/todo', methods=['POST'])
def create_todo():
    data = request.get_json()
    title = data.get('title')
    with sqlite3.connect('todo.db') as conn:
        cursor = conn.cursor()
        cursor.execute('INSERT INTO todos (title, completed) VALUES (?, ?)', (title, False))
        conn.commit()
        new_task_id = cursor.lastrowid
    return jsonify({'id': new_task_id, 'title': title, 'completed': False}), 201

@app.route('/todo', methods=['GET'])
def get_todos():
    with sqlite3.connect('todo.db') as conn:
        cursor = conn.cursor()
        cursor.execute('SELECT * FROM todos')
        todos = cursor.fetchall()
        todo_list = [{'id': row[0], 'title': row[1], 'completed': bool(row[2])} for row in todos]
    return jsonify(todo_list), 200

@app.route('/todo/<int:todo_id>', methods=['PUT'])
def mark_completed(todo_id):
    with sqlite3.connect('todo.db') as conn:
        cursor = conn.cursor()
        cursor.execute('UPDATE todos SET completed = ? WHERE id = ?', (True, todo_id))
        if cursor.rowcount == 0:
            return jsonify({'error': 'Task not found'}), 404
        conn.commit()
    return jsonify({'id': todo_id, 'completed': True}), 200

@app.route('/todo/<int:todo_id>', methods=['DELETE'])
def delete_todo(todo_id):
    with sqlite3.connect('todo.db') as conn:
        cursor = conn.cursor()
        cursor.execute('DELETE FROM todos WHERE id = ?', (todo_id,))
        if cursor.rowcount == 0:
            return jsonify({'error': 'Task not found'}), 404
        conn.commit()
    return jsonify({'message': 'Task deleted'}), 200

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