Watch API

1from crawlingo import Watch
2import asyncio
3
4def on_change(event):
5    print(f"[{event.event_type}] '{event.field}' changed!")
6    print(f"  Old: {event.old_value}")
7    print(f"  New: {event.new_value}")
8
9async def main():
10    watcher = (
11        Watch("https://example.com/product/1")
12        .field("title", "h1")
13        .field("price", "span.price", extraction_type="price")
14        .interval(60)                           # Poll every 60 seconds
15        .on_change(on_change)
16    )
17
18    watch_task = asyncio.create_task(watcher.run_async())
19    await asyncio.sleep(3600)
20    watcher.stop()
21    await watch_task
22
23asyncio.run(main())

1import { Watch } from 'crawlingo';
2
3const watcher = new Watch('https://example.com/product/1')
4  .field('title', 'h1')
5  .field('price', 'span.price', { extractionType: 'price' })
6  .interval(60);
7
8watcher.run((err, event) => {
9  if (err) return console.error(err);
10  console.log(`[${event.changeType}] ${event.field} changed!`);
11  console.log(`  Old: ${event.oldValue}`);
12  console.log(`  New: ${event.newValue}`);
13});