import * as Koa from 'koa'; import summaly from 'summaly'; module.exports = async (ctx: Koa.Context) => { const summary = await summaly(ctx.query.url); summary.icon = wrap(summary.icon); summary.thumbnail = wrap(summary.thumbnail); // Cache 7days ctx.set('Cache-Control', 'max-age=604800, immutable'); ctx.body = summary; }; function wrap(url: string): string { return url != null ? url.startsWith('https://') || url.startsWith('data:') ? url : `https://images.weserv.nl/?url=${encodeURIComponent(url.replace(/^http:\/\//, ''))}` : null; }