eater

node 学園付属小学校の2回目で話した eater の話です。

Transcript

1. Eater @yosuke_furukawa
2. @yosuke_furukawa
3. Hello, Noders. This is Full-time Papa committer
5. child_process.spawn()
7. Node Quiz
8. Quiz: child_process API ͷԼهͷ ҧ͍͸ԿͰ͠ΐ͏ 1. exec 2. spawn 3. fork
9. A: spawn ͕Ұ൪ϩʔϨϕϧ exec/fork ͸ spawn ͷ wrapper
10. A: exec ͸ callback Ͱड͚Δɺ fork ͸ JavaScript ͷίʔυ Λ Node.js ͱͯ͠࠶࣮ߦ͢Δ
11. child_process.spawn const spawn = require('child_process').spawn; const ls = spawn('ls', [‘-al']); ls.stdout.on('data', (data) => { console.log(data); }); ls.stderr.on('data', (data) => { console.log(data); }); ls.on('exit', (code) => { if (code !== 0) console.error(`Error occurred`); });
12. child_process.exec const exec = require('child_process').exec; exec(‘ls -al‘, (err, stdout, stderr) => { console.log(`${stdout}`); console.error(`${stderr}`); if (error !== null) { console.error(`Error occurred`); } });
13. child_process.fork const fork = require('child_process').fork; const ls = fork(‘ls.js’); ls.stdout.on('data', (data) => { console.log(data); }); ls.stderr.on('data', (data) => { console.log(data); }); ls.on('exit', (code) => { if (code !== 0) console.error(`Error occurred`); });
14. spawn > exec ͜ͷॱͰ simple exec > spawn ͜ͷॱͰ easy spawn > fork ͜ͷॱͰ simple fork > spawn ͜ͷॱͰ easy
15. Easy / Simple ͷҧ͍
17. Simple !== Easy
18. Simple is “୯७” ٬؍తɺҰͭͷࣄ͔͠͠ͳ͍
19. Easy is “؆୯” ओ؍తɺ”୭͔”ʹͱͬͯ؆୯ “୭ʹͱͬͯ΋؆୯”͸ ଘࡏ͠ͳ͍
20. ॳ৺ऀ͕ؕΓ͕ͪͳࣄɿ Easy ͷݴ༿ʹὃ͞Ε͕ͪ ୭ʹͱͬͯ΋Easy ͳΜͯ͋Γ ͑ͳ͍
21. ॳ৺ऀ͕ؕΓ͕ͪͳࣄɿ Simple ͱ Easy Λࠞಉ͍ͯ͠ Δ࿩ʹࠔ࿭͞Ε͕ͪ
22. Eater
23. Eater is *Ea*sy *t*est runn*er*
24. Eater has one simple rule If test file outputs `stderr` message, the test failed.
25. Easy => ୭ʹͱͬͯʁ `node` ͔͠஌Βͳ͍Α͏ͳਓ mocha/jestͷࡉ͔͍ߏจΛ֮ ͑ͯͳͯ͘ɺnode ίϚϯυ ͰεΫϦϓτͱ࣮ͯ͠ߦ͢Δ ͚ͩͰΠφϑͳਓ
26. Eaterͷtest script͸ `node` command Ͱ΋࣮ߦͰ͖Δ
27. Easy => ୭ʹͱͬͯʁ mock/spyΛଟ༻͢Δ͚Ͳɺ mock/spyͷ։์࿙ΕΛ๨Ε ͕ͪͳਓʹͱͬͯ
28. Eaterͷtest͸ҰͭҰ͕ͭผϓ ϩηεͰ࣮ߦ͞ΕΔ
29. mockΛ։์͠ͳͯ͘OK // you don’t need to fix mock/spy console.log => (message) { assert(message.match(/Foo Bar/)); }; const mockDate = new Date(2016, 3, 9); Date.now = () => { return mockDate.valueOf(); }; process.exit => (exitcode) { assert(exitcode === 1); };
30. ͔͠΋ϓϩηε਺͸ίΞ਺Ͱ ಄ଧͪʹͳΔ eater ——procs 4 ※procs optionͰՄม
31. Eater DEMO https://github.com/yosuke- furukawa/eater-demo
32. Happy Eater https://github.com/yosuke- furukawa/eater