Node.jsでTOON — ファイルI/OからLLMパイプラインまで

npm install @toon-format/toon

import { encode, decode } from '@toon-format/toon';

// That's it. encode() → TOON string, decode() → JS value.

// --- Sync (scripts, CLI tools) ---
import { readFileSync, writeFileSync } from 'fs';
import { encode, decode } from '@toon-format/toon';

// Read a .toon file and decode it to a JS value
const raw = readFileSync('./data/products.toon', 'utf8');
const products = decode(raw);
console.log(products); // → JS array or object

// Encode a JS value and write it to a .toon file
const inventory = [
  { sku: 'WDG-001', name: 'Widget A', qty: 142, price: 9.99 },
  { sku: 'WDG-002', name: 'Widget B', qty: 87,  price: 14.49 },
  { sku: 'GDG-001', name: 'Gadget X', qty: 31,  price: 49.99 },
];
writeFileSync('./data/inventory.toon', encode(inventory, { indent: 2 }), 'utf8');

// --- Async (server routes, pipelines) ---
import { promises as fs } from 'fs';
import { encode, decode } from '@toon-format/toon';

// Read
async function loadReportData(filePath) {
  const raw = await fs.readFile(filePath, 'utf8');
  return decode(raw); // throws if malformed — handle upstream
}

// Write
async function saveSnapshot(data, filePath) {
  const toon = encode(data, { indent: 2 });
  await fs.writeFile(filePath, toon, 'utf8');
}

import { decode } from '@toon-format/toon';

/**
 * Safely parse a TOON string.
 * Returns { valid: true, data } on success,
 * or { valid: false, error } on failure — never throws.
 */
export function validateToon(input) {
  if (typeof input !== 'string') {
    return { valid: false, error: 'Input must be a string' };
  }
  try {
    const data = decode(input);
    return { valid: true, data };
  } catch (err) {
    return { valid: false, error: err.message };
  }
}

// Example: queue consumer
queue.process('ingest-toon', async (job) => {
  const result = validateToon(job.data.payload);
  if (!result.valid) {
    console.error('Rejecting malformed TOON:', result.error);
    return; // dead-letter, skip, or throw depending on your queue
  }
  await db.insert(result.data);
});

import { decode } from '@toon-format/toon';

/**
 * Express middleware: parses application/toon request bodies
 * and attaches the decoded value to req.body.
 */
export function toonBodyParser(req, res, next) {
  const contentType = req.headers['content-type'] ?? '';
  if (!contentType.includes('application/toon')) {
    return next(); // not our content type, pass through
  }

  let body = '';
  req.setEncoding('utf8');
  req.on('data', (chunk) => { body += chunk; });
  req.on('end', () => {
    try {
      req.body = decode(body);
      next();
    } catch (err) {
      res.status(400).json({ error: 'Invalid TOON body', detail: err.message });
    }
  });
  req.on('error', (err) => {
    res.status(500).json({ error: 'Request stream error', detail: err.message });
  });
}

// Wire it up:
// app.use(toonBodyParser);
// app.post('/api/import', (req, res) => {
//   // req.body is already the decoded JS value
//   res.json({ received: Array.isArray(req.body) ? req.body.length : 1 });
// });

import pg from 'pg';
import { encode } from '@toon-format/toon';

const pool = new pg.Pool({ connectionString: process.env.DATABASE_URL });

async function buildOrderPrompt(customerId) {
  // Step 1: query the database
  const { rows } = await pool.query(
    `SELECT order_id, created_at, status, total_cents, item_count
       FROM orders
      WHERE customer_id = $1
      ORDER BY created_at DESC
      LIMIT 50`,
    [customerId]
  );

  if (rows.length === 0) {
    return null;
  }

  // Step 2: encode rows to TOON
  // encode() handles all quoting automatically — no pre-processing needed
  const toonData = encode(rows, { indent: 2 });

  // Step 3: build the prompt
  return [
    'Analyse the following order history for a customer support case.',
    'Data is in TOON tabular format: name[count]{col1,col2,...}: followed by one row per line.',
    '',
    toonData,
    '',
    'Summarise any patterns that suggest the customer has a recurring issue.'
  ].join('\n');
}

// Calling code:
const prompt = await buildOrderPrompt('cust_8821');
if (prompt) {
  const reply = await callLlm(prompt); // your LLM client here
  console.log(reply);
}