Observable Proposal implement based on Async Generator (ES 2018) & TypeScript
import { Observable } from 'iterable-observer'; var count = 0, list = []; const observable = new Observable(({ next, complete }) => { const timer = setInterval( () => (++count < 5 ? next(count) : complete(count)), 0 ); return () => clearInterval(timer); }); (async () => { for await (const item of observable) list.push(item); console.log(list); // [1, 2, 3, 4, 5] })();import { Observable } from 'iterable-observer'; const reader = new FileReader(), { files } = document.querySelector('input[type="file"]'); reader.readAsBlob(files[0]); (async () => { for await (const { loaded } of Observable.fromEvent(reader, 'progress')) console.log((loaded / file.size) * 100 + '%'); })();import { Observable } from 'iterable-observer'; (async () => { const { body } = await fetch('https://example.com/path/to/blob'), chunks: Uint8Array[] = []; for await (const chunk of Observable.fromStream(body)) chunks.push(chunk); const blob = new Blob(chunks); console.log(blob); }();import { createQueue } from 'iterable-observer'; import Koa from 'koa'; import BodyParser from 'koa-bodyparser'; const { process, observable } = createQueue(), app = new Koa(); (async () => { for await (const { defer, data } of observable) defer.resolve(JSON.stringify(data)); })(); app.use(BodyParser) .use(async context => (context.body = await process(context.request.body))) .listen(80);