ttlcacheのここがスゴい

Fukuoka.go#20 でお話しました。

Transcript

1. 🍉🌴🏄 GoConference’19 🏄🌴🍉 ttlcacheͷ͕͜͜εΰ͍ - genericsɺطଘͷίʔυɺஔ͖׵͍͑ͨ -
2. 🍉🌴🏄 GoConference’19 🏄🌴🍉 ࢁԼ ࿨඙ @pyama86 <?php $pro fi le = [ 'ॴଐ' => 'GMOϖύϘ ٕज़ج൫νʔϜ', ‘ݞॻ' => 'γχΞɾϓϦϯγύϧ', 'झຯ' => ['ώϧτϯ८Γ', 'Ωϟϯϓ', ‘ཱྀߦ’,’εϚϒϥ’], '΢ΣϒαΠτ' => [ 'life' => 'http://pyama.fun', 'stns' => 'http://stns.jp', ], ]; 2
3. 🍉🌴🏄 GoConference’19 🏄🌴🍉 Go͸ΫϥΠΞϯτΩϟογϡ͕ͨ͘͞Μ͋Δ wIUUQTHJUIVCDPNFLPHPDBDIF
   wIUUQTHJUIVCDPNIBTIJDPSQHPMBOHMSV
   wIUUQTHJUIVCDPNKFMMZEBUPSUUMDBDIF 3 IUUQTHJUIVCDPNBWFMJOPBXFTPNFHP
4. 🍉🌴🏄 GoConference’19 🏄🌴🍉 ttlcache w ػೳ͕গͳ͍γϯϓϧͳ
   55-෇͖ͷΦϯϝϞϦΩϟογϡ
   w σϑΥϧτ͸55-͕ࣗಈԆ௕͞ΕΔ
   w Ϩίʔυͷ௥Ճ࣌ɺ࡟আ࣌ʹ
   ϑοΫ͕࣮ߦͰ͖Δ
   w -PBEFS΋͋ΓଟॏΫΤϦΛ཈੍Ͱ͖Δ 4 package main import ( "time" "github.com/jellydator/ttlcache" ) func main() { cache := ttlcache.New[string, string]( ttlcache.WithTTL[string, string](time.Minute), ) go cache.Start() }
5. 🍉🌴🏄 GoConference’19 🏄🌴🍉 Hooks 5 cache.OnInsertion(func(ctx context.Context, item *ttlcache.Item[string, string]) { tracer.Increment(item.Value(), item.ExpiresAt()) }) cache.OnEviction(func(ctx context.Context, reason ttlcache.EvictionReason, item *ttlcache.Item[string, string]) { if reason == ttlcache.EvictionReasonCapacityReached { slack.Notify(item.Value(), item.ExpiresAt()) } }) ௨஌ͨ͠ΓɺΧ΢ϯλʔΛೖΕͨΓ
6. 🍉🌴🏄 GoConference’19 🏄🌴🍉 Loader 6 Ωϟογϡ͕੾Εͨͱ͖ʹଟॏʹϩʔυ͞ΕΔ໰୊
7. 🍉🌴🏄 GoConference’19 🏄🌴🍉 Loader 7 loader := ttlcache.LoaderFunc[…](func(…, key string)) *ttlcache.Item[string, int] { return runQuery(fmt.Sprintf(`SELECT * FROM name = “%s”`, key) }) group := &singleflight.Group{} sl := ttlcache.NewSuppressedLoader[string, string](loader, group) cache := ttlcache.New[string, int]( ttlcache.WithTTL[string, int](30*time.Minute), ttlcache.WithLoader[string, int](sl), ) cache.Get(“gopher”) Ωϟογϡ͕ͳ͍ͱ͖ʹɺϩʔυ͢ΔίʔϧόοΫ
8. 🍉🌴🏄 GoConference’19 🏄🌴🍉 single fl ight.Group 8 var g singleflight.Group for i := 0; i < 3; i++ { go func(i int) { v, _, _ := g.Do("cache_key", func() (interface{}, error) { fmt.Println("Fetching from origin...") time.Sleep(2 * time.Second) return "response_data", nil }) fmt.Printf("Result for goroutine %d: %v\n", i, v) }(i) } ଟॏ࣮ߦΛҰͭͷ࣮ߦʹ·ͱΊΔ͜ͱ͕Ͱ͖Δ
9. 🍉🌴🏄 GoConference’19 🏄🌴🍉 single fl ight.Group 9 Fetching from origin... Result for goroutine 0: response_data Result for goroutine 1: response_data Result for goroutine 2: response_data ϑΣον͸ճɺ݁Ռ͸ߦ 'FUDI͸ճ͚࣮ͩߦ
10. 🍉🌴🏄 GoConference’19 🏄🌴🍉 ttlcacheͷ͕͜͜εΰ͍ wػೳ͕গͳ͍
    
    ίʔυ͕௥͍΍͍͢͠ɺ֮͑Δ͜ͱ͕͘͢ͳ͍
    wΦϯϝϞϦΩϟογϡ͚ͩͳΒඞཁे෼
    w3FEJTͱ૊Έ߹ΘͤΔͱ͔ͳΒଞͷύοέʔδ࢖ͬͨ΄͏͕ྑ͍ 10
11. 🍉🌴🏄 GoConference’19 🏄🌴🍉 શͯͷࣄۀͰ࠾༻͠·͍ͬͯ͘·͢ !QC@SFDSVJU 11