タスクを見失わずに GPT Image 2 をバッチ実行する

import { mkdir, readFile, rename, writeFile } from 'node:fs/promises';

const mode = process.argv[2];
if (!['submit', 'poll'].includes(mode)) {
  throw new Error('Use: node images.mjs submit | poll');
}
const key = process.env.SEEDROUTER_API_KEY;
if (!key) throw new Error('Set SEEDROUTER_API_KEY on your server.');
const base = 'https://api.seedrouter.ai/v1';
const headers = { Authorization: `Bearer ${key}` };
const file = 'image-tasks.json';
let state;
try {
  state = JSON.parse(await readFile(file, 'utf8'));
} catch (error) {
  if (error.code !== 'ENOENT') throw error;
  state = {};
}
const save = async () => {
  await writeFile(`${file}.tmp`, JSON.stringify(state, null, 2), { mode: 0o600 });
  await rename(`${file}.tmp`, file);
};
const pause = () => new Promise((resolve) => setTimeout(resolve, 3000));
const jobs = [
  ['blue-mug', 'A cobalt-blue ceramic mug on a pale gray tabletop.'],
  ['green-bowl', 'A green ceramic bowl on a pale gray tabletop.'],
];

if (mode === 'submit') {
  for (const [name, prompt] of jobs) {
    if (state[name]) continue;
    state[name] = { status: 'unconfirmed' };
    await save();
    try {
      const response = await fetch(`${base}/images/generations`, {
        method: 'POST',
        headers: { ...headers, 'Content-Type': 'application/json' },
        body: JSON.stringify({
          model: 'gpt-image-2', prompt,
          size: '1024x1024', quality: 'low', output_format: 'png', n: 1,
        }),
        signal: AbortSignal.timeout(60000),
      });
      const task = await response.json();
      if (typeof task.id === 'string' && task.id) {
        state[name] = { id: task.id, status: 'processing' };
        await save();
      }
      if (!response.ok || !state[name].id) {
        throw new Error('Submission needs review.');
      }
    } catch {
      console.error(`${name}: stopped; inspect the saved state before continuing.`);
      process.exitCode = 1;
      break;
    }
  }
} else {
  await mkdir('images', { recursive: true });
  const deadline = Date.now() + 600000;
  do {
    for (const [name, entry] of Object.entries(state)) {
      if (!entry.id || entry.status === 'failed' || entry.downloaded) continue;
      try {
        const response = await fetch(`${base}/tasks/${encodeURIComponent(entry.id)}`, {
          headers, signal: AbortSignal.timeout(30000),
        });
        if (!response.ok) throw new Error('Task check failed.');
        const task = await response.json();
        if (!['processing', 'completed', 'failed'].includes(task.status)) {
          throw new Error('Unexpected task status.');
        }
        entry.status = task.status;
        await save();
        if (task.status !== 'completed') continue;
        const images = task.output?.data;
        if (!Array.isArray(images) || !images.length) {
          throw new Error('Completed task has no image URLs.');
        }
        for (const [index, image] of images.entries()) {
          const url = new URL(image.url);
          if (url.protocol !== 'https:') throw new Error('Expected an HTTPS image URL.');
          // The download is a separate request: never attach the API key.
          const result = await fetch(url, { signal: AbortSignal.timeout(60000) });
          if (!result.ok || !result.headers.get('content-type')?.startsWith('image/png')) {
            throw new Error('PNG download failed.');
          }
          await writeFile(`images/${name}-${index}.png`, Buffer.from(await result.arrayBuffer()));
        }
        entry.downloaded = true;
        await save();
      } catch {
        console.error(`${name}: check or download incomplete; task ID retained.`);
      }
    }
    if (!Object.values(state).some((entry) => entry.id && entry.status !== 'failed' && !entry.downloaded)) break;
    await pause();
  } while (Date.now() < deadline);
}
console.log(JSON.stringify(state, null, 2));