perfect-postcode/screenshot/src/server.ts
2026-03-15 17:38:26 +00:00

114 lines
3.2 KiB
TypeScript

import express from 'express';
import { ScreenshotCache } from './cache.js';
import { takeScreenshot, checkWebGL, closeBrowser, initialize } from './screenshot.js';
const PORT = parseInt(process.env.PORT || '8002', 10);
const APP_URL = process.env.APP_URL;
const CACHE_DIR = process.env.CACHE_DIR;
if (!APP_URL) {
console.error('Error: APP_URL environment variable is required');
process.exit(1);
}
if (!CACHE_DIR) {
console.error('Error: CACHE_DIR environment variable is required');
process.exit(1);
}
const cache = new ScreenshotCache(CACHE_DIR);
const app = express();
app.get('/health', (_req, res) => {
res.status(200).send('ok');
});
app.get('/debug', async (_req, res) => {
try {
const info = await checkWebGL();
res.json(info);
} catch (err) {
res.status(500).json({ error: String(err) });
}
});
app.get('/screenshot', async (req, res) => {
try {
const qs = new URLSearchParams();
for (const key of ['lat', 'lon', 'zoom', 'tab', 'og']) {
const val = req.query[key];
if (typeof val === 'string' && val) {
qs.set(key, val);
}
}
// Repeated params: filter, poi
for (const key of ['filter', 'poi']) {
const val = req.query[key];
if (typeof val === 'string' && val) {
qs.append(key, val);
} else if (Array.isArray(val)) {
for (const v of val) {
if (typeof v === 'string' && v) qs.append(key, v);
}
}
}
// Extract path param (used for non-root pages like /invite/CODE)
const pagePath = typeof req.query.path === 'string' && req.query.path ? req.query.path : '/';
if (pagePath !== '/') qs.set('path', pagePath);
const cacheKey = cache.buildKey(qs);
qs.delete('path');
// Check cache first
const cached = cache.get(cacheKey);
if (cached) {
res.setHeader('Content-Type', 'image/jpeg');
res.setHeader('Cache-Control', 'public, max-age=86400');
res.setHeader('X-Cache', 'HIT');
cached.pipe(res);
return;
}
// Build the URL for the frontend in screenshot mode
qs.set('screenshot', '1');
const url = `${APP_URL}${pagePath}?${qs}`;
console.log(`Taking screenshot: ${url}`);
const jpeg = await takeScreenshot(url);
// Cache it
cache.set(cacheKey, jpeg);
res.setHeader('Content-Type', 'image/jpeg');
res.setHeader('Cache-Control', 'public, max-age=86400');
res.setHeader('X-Cache', 'MISS');
res.send(jpeg);
} catch (err) {
console.error('Screenshot failed:', err);
res.status(500).json({ error: 'Screenshot failed' });
}
});
const server = app.listen(PORT, () => {
console.log(`Screenshot service listening on port ${PORT}`);
console.log(` APP_URL: ${APP_URL}`);
console.log(` CACHE_DIR: ${CACHE_DIR}`);
// Pre-warm browser and populate network cache in background.
// The health endpoint is available immediately; screenshot requests
// during warm-up will still work (just slower on the first call).
initialize(APP_URL).catch((err) => {
console.error('Initialization failed:', err);
});
});
// Graceful shutdown
for (const signal of ['SIGTERM', 'SIGINT']) {
process.on(signal, async () => {
console.log(`Received ${signal}, shutting down...`);
server.close();
await closeBrowser();
process.exit(0);
});
}