From 6e46c977e8573d4c3ac5f1297321497e57c030be Mon Sep 17 00:00:00 2001 From: Hidekazu Kobayashi Date: Sat, 7 Oct 2023 05:52:04 +0000 Subject: [PATCH 1/2] Implement DebounceLoader --- packages/backend/src/misc/loader.ts | 49 +++++++++++++ packages/backend/test/unit/misc/loader.ts | 88 +++++++++++++++++++++++ 2 files changed, 137 insertions(+) create mode 100644 packages/backend/src/misc/loader.ts create mode 100644 packages/backend/test/unit/misc/loader.ts diff --git a/packages/backend/src/misc/loader.ts b/packages/backend/src/misc/loader.ts new file mode 100644 index 0000000000..49aac5d883 --- /dev/null +++ b/packages/backend/src/misc/loader.ts @@ -0,0 +1,49 @@ +export type FetchFunction = (key: K) => Promise; +type ResolveReject = Parameters>[0]>; +type ResolverPair = { + resolve: ResolveReject[0]; + reject: ResolveReject[1]; +}; +export class DebounceLoader { + private resolverMap = new Map>(); + private promiseMap = new Map>(); + private resolvedPromise = Promise.resolve(); + constructor(private loadFn: FetchFunction) {} + + public load(key: K): Promise { + const promise = this.promiseMap.get(key); + if (typeof promise !== 'undefined') { + return promise; + } + + const isFirst = this.promiseMap.size === 0; + const newPromise = new Promise((resolve, reject) => { + this.resolverMap.set(key, { resolve, reject }); + }); + this.promiseMap.set(key, newPromise); + + if (isFirst) { + this.enqueueDebouncedLoadJob(); + } + + return newPromise; + } + + private runDebouncedLoad(): void { + const resolvers = [...this.resolverMap]; + this.resolverMap.clear(); + this.promiseMap.clear(); + + for (const [key, { resolve, reject }] of resolvers) { + this.loadFn(key).then(resolve, reject); + } + } + + private enqueueDebouncedLoadJob(): void { + this.resolvedPromise.then(() => { + process.nextTick(() => { + this.runDebouncedLoad(); + }); + }); + } +} diff --git a/packages/backend/test/unit/misc/loader.ts b/packages/backend/test/unit/misc/loader.ts new file mode 100644 index 0000000000..fa37950951 --- /dev/null +++ b/packages/backend/test/unit/misc/loader.ts @@ -0,0 +1,88 @@ +import { DebounceLoader } from '@/misc/loader.js'; + +class Mock { + loadCountByKey = new Map(); + load = async (key: number): Promise => { + const count = this.loadCountByKey.get(key); + if (typeof count === 'undefined') { + this.loadCountByKey.set(key, 1); + } else { + this.loadCountByKey.set(key, count + 1); + } + return key * 2; + }; + reset() { + this.loadCountByKey.clear(); + } +} + +describe(DebounceLoader, () => { + describe('single request', () => { + it('loads once', async () => { + const mock = new Mock(); + const loader = new DebounceLoader(mock.load); + expect(await loader.load(7)).toBe(14); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(7)).toBe(1); + }); + }); + + describe('two duplicated requests at same time', () => { + it('loads once', async () => { + const mock = new Mock(); + const loader = new DebounceLoader(mock.load); + const [v1, v2] = await Promise.all([ + loader.load(7), + loader.load(7), + ]); + expect(v1).toBe(14); + expect(v2).toBe(14); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(7)).toBe(1); + }); + }); + + describe('two different requests at same time', () => { + it('loads twice', async () => { + const mock = new Mock(); + const loader = new DebounceLoader(mock.load); + const [v1, v2] = await Promise.all([ + loader.load(7), + loader.load(13), + ]); + expect(v1).toBe(14); + expect(v2).toBe(26); + expect(mock.loadCountByKey.size).toBe(2); + expect(mock.loadCountByKey.get(7)).toBe(1); + expect(mock.loadCountByKey.get(13)).toBe(1); + }); + }); + + describe('non-continuous same two requests', () => { + it('loads twice', async () => { + const mock = new Mock(); + const loader = new DebounceLoader(mock.load); + expect(await loader.load(7)).toBe(14); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(7)).toBe(1); + mock.reset(); + expect(await loader.load(7)).toBe(14); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(7)).toBe(1); + }); + }); + + describe('non-continuous different two requests', () => { + it('loads twice', async () => { + const mock = new Mock(); + const loader = new DebounceLoader(mock.load); + expect(await loader.load(7)).toBe(14); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(7)).toBe(1); + mock.reset(); + expect(await loader.load(13)).toBe(26); + expect(mock.loadCountByKey.size).toBe(1); + expect(mock.loadCountByKey.get(13)).toBe(1); + }); + }); +}); From b70ae7a6145dae62847f50ecdd36bdb3f684a07f Mon Sep 17 00:00:00 2001 From: Hidekazu Kobayashi Date: Sat, 7 Oct 2023 05:55:36 +0000 Subject: [PATCH 2/2] Debounce notes.findOneOrFail in NoteEntityService.pack --- .../backend/src/core/entities/NoteEntityService.ts | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/packages/backend/src/core/entities/NoteEntityService.ts b/packages/backend/src/core/entities/NoteEntityService.ts index cad850b860..987c9a3016 100644 --- a/packages/backend/src/core/entities/NoteEntityService.ts +++ b/packages/backend/src/core/entities/NoteEntityService.ts @@ -26,6 +26,7 @@ import type { } from '@/models/index.js'; import { bindThis } from '@/decorators.js'; import { isNotNull } from '@/misc/is-not-null.js'; +import { DebounceLoader } from '@/misc/loader.js'; import type { OnModuleInit } from '@nestjs/common'; import type { CustomEmojiService } from '../CustomEmojiService.js'; import type { ReactionService } from '../ReactionService.js'; @@ -38,6 +39,7 @@ export class NoteEntityService implements OnModuleInit { private driveFileEntityService: DriveFileEntityService; private customEmojiService: CustomEmojiService; private reactionService: ReactionService; + private noteLoader = new DebounceLoader(this.findNoteOrFail); constructor( private moduleRef: ModuleRef, @@ -304,7 +306,7 @@ export class NoteEntityService implements OnModuleInit { }, options); const meId = me ? me.id : null; - const note = typeof src === 'object' ? src : await this.notesRepository.findOneOrFail({ where: { id: src }, relations: ['user'] }); + const note = typeof src === 'object' ? src : await this.noteLoader.load(src); const host = note.userHost; let text = note.text; @@ -483,4 +485,12 @@ export class NoteEntityService implements OnModuleInit { return await query.getCount(); } + + @bindThis + private async findNoteOrFail(id: string): Promise { + return await this.notesRepository.findOneOrFail({ + where: { id }, + relations: ["user"], + }); + } }