NodeFest2018/Node v10-v11

Transcript

1. NodeFest 2018 2018/10/30 @yosuke_furukawa
2. NodeFest 2018 ։࠵͠·͢ʂʂʂʂ
3. New Logo
5. Stickers, T-Shirts, Mugs are getting ready !!!
6. Day1: Conference
7. Featured Speakers
13. ͜ͷଞʹ΋
15. ॻ͖͖Εͳ͍΄Ͳίϯςϯπ͋Γ·͢ʂʂʂʂ
16. Day2: Interactive Sessions
17. Node/JS Discussion
18. Node/JS Discussion
19. Node/JS Discussion ΈΜͳͰҰॹʹ/PEF+4ͷྑ͍ͱ͜Ζɾѱ͍ͱ͜Ζɾ վળ఺Λॻ͖·͠ΐ͏
20. Code And Learn
21. Code And Learn ΈΜͳͰ/PEFKT
    ʹ13ΛૹͬͯΈΔձ
22. Code And Learn ݁Ռͱͯ͠ਓͷ/PEF
    ίϛολʔΛ࡞Δ͜ͱ͕ग़ དྷ·ͨ͠ʂʂʂ
23. Handson
24. Handson
25. Handson
26. Handson
27. Handson
28. Handson
29. After Party
30. ࠓ೥΋͋Γ·͢ʂʂ Video Jockey!!!
31. ΈΜͳདྷͯͶʂʂʂʂ http://bit.ly/nodefest2018-1 http://bit.ly/nodefest2018-2
32. Node.js v10/v11
 ৘ใ 2018/10/30 @yosuke_furukawa
33. CodeGrid ʹدߘத
34. Node.js v10.0.0 ~ v10.12.0 • HTTP/2 • ES Modules • Error Code ʹΑΔϋϯυϦϯά • fs ʹ promises ͕௥Ճ͞Εͨ • Stream͕վળ͞Εͨ • Worker͕վળ͞Εͨ
35. Node.js v11 • V8 version 7.0ରԠ (wasm վળ) • url module ͕ deprecated ʹͳΓɺ WHATWG URL Λར༻͢ΔΑ͏ʹ಺෦վળ͕ߦΘΕͨ • TextEncoder/TextDecoder͕globalʹͳͬͨ • queueMicrotask API ͕࣮ݧతʹ௥Ճ͞Εͨ
36. Stream/Promiseͷ਌࿨ੑվળ • for await of Ͱ Stream Λஞ࣍ॲཧͰ͖ΔΑ͏ ʹͳͬͨ • Node v10 ͔Β Stream ʹ௥Ճ͞Εͨ finished, pipeline API͕ Promiseͱͷ਌࿨ੑߴ͍
37. for await of ͷվળ const fs = require('fs'); async function print(readable) { readable.setEncoding('utf8'); let data = ''; // for await ۟Ͱiterateͭͭ͠ɺchunkΛऔΓग़͢ for await (const k of readable) { data += k; } console.log(data); } print(fs.createReadStream('file')).catch(console.log);
38. Stream finished API const fs = require('fs'); const { finished } = require('stream'); const rs = fs.createReadStream('./stream.js'); //finished API ͰΤϥʔऴྃɺਖ਼ৗऴྃʹ͔͔ΘΒͣऴྃͨ͠ΒίʔϧόοΫΛݺ΂Δɻ finished(rs, (err) => { if (err) { console.error('Stream failed', err); return; } console.log('Stream is done reading'); }); rs.resume();
39. Stream finished API const fs = require('fs'); const util = require('util'); const stream = require('stream'); // Promisify Λ࢖ͬͯcallbackΛpromiseʹ͢Δ const finished = util.promisify(stream.finished); const rs = fs.createReadStream('./stream.js'); // async await ͕࢖͑Δ async function run() { await finished(rs); console.log('Stream is done reading'); } run().catch((err) => console.error('Stream failed', err)); rs.resume();
40. Stream Pipeline API const fs = require('fs'); const rs = fs.createReadStream('error.txt'); const ws = fs.createWriteStream('output.txt'); rs.pipe(ws).on("error", (e) => { // ͜͜Ͱ౷ҰతʹΤϥʔΛϋϯυϦϯά͍͕ͨ͠ɺ // readstreamͰΤϥʔʹͳΔͱ͜͜ʹདྷͳ͍ɻ // ͜͏΍ͬͯॻ͔ͳͯ͘͸͍͚ͳ͍ // rs.on("error", errorHandler).pipe(ws).on("error", errorHandler) });
41. Stream Pipeline API const { pipeline, Transform } = require('stream'); const rs = fs.createReadStream('./stream.js'); const ts = new Transform({ transform(chunk, encoding, callback) { callback(null, chunk.toString().toUpperCase()) } }); const ws = fs.createWriteStream('./stream_cap.js'); pipeline(rs, ts, ws, (err) => { if (err) { console.error(err); return; } console.log('Stream is done reading'); }); rs.resume();
42. Stream Pipeline API const { pipeline, Transform } = require('stream'); const p = util.promisify(pipeline); const rs = fs.createReadStream('./stream.js'); const ts = new Transform({ transform(chunk, encoding, callback) { callback(null, chunk.toString().toUpperCase()) } }); const ws = fs.createWriteStream('./stream_cap.js'); // promisify ͔ͯ͠Β async-awaitͰ͖Δ async function run() { await p(rs, ts, ws); console.log('Stream is done reading'); } run().catch(console.error); rs.resume();
43. Promise ଆ΋͍͔ͭ͘վળ • Promise͕ෳ਺ճresolve, reject͞Εͨͱ͖ʹ ϋϯυϦϯά͢Δɺ multipleResolves ͕௥Ճ • queueʹ௚઀MicrotaskΛੵΉɺ queueMicrotask API ͕௥Ճ͞Εͨɻ
44. process.on('multipleResolves ') process.on('multipleResolves', (type, promise, reason) => { console.error(type, promise, reason); setImmediate(() => process.exit(1)); }); async function main() { try { return await new Promise((resolve, reject) => { resolve('First call'); resolve('Swallowed resolve'); reject(new Error('Swallowed reject')); }); } catch { throw new Error('Failed'); } }
45. queueMicrotask DataHandler.prototype.load = async function load(key) { const hit = this._cache.get(url); if (hit !== undefined) { queueMicrotask(() => { this.emit('load', hit); }); return; } const data = await fetchData(key); this._cache.set(url, data); this.emit('load', data); };
46. Why Node needs web standard? James Snell @ NodeFest 2016
 Node.js is, and has been, primarily a platform for Web Application Development While Node.js presumes a "small core" philosophy for most things, it includes support for the most basic and critical internet standards