paricafe/packages/backend/src/core/FunoutTimelineService.ts
2023-10-18 12:26:16 +09:00

85 lines
3 KiB
TypeScript

/*
* SPDX-FileCopyrightText: syuilo and other misskey contributors
* SPDX-License-Identifier: AGPL-3.0-only
*/
import { Inject, Injectable } from '@nestjs/common';
import * as Redis from 'ioredis';
import { DI } from '@/di-symbols.js';
import { bindThis } from '@/decorators.js';
import { IdService } from '@/core/IdService.js';
@Injectable()
export class FunoutTimelineService {
constructor(
@Inject(DI.redisForTimelines)
private redisForTimelines: Redis.Redis,
private idService: IdService,
) {
}
@bindThis
public push(tl: string, id: string, maxlen: number, pipeline: Redis.ChainableCommander) {
// リモートから遅れて届いた(もしくは後から追加された)投稿日時が古い投稿が追加されるとページネーション時に問題を引き起こすため、
// 3分以内に投稿されたものでない場合、Redisにある最古のIDより新しい場合のみ追加する
if (this.idService.parse(id).date.getTime() > Date.now() - 1000 * 60 * 3) {
pipeline.lpush('list:' + tl, id);
if (Math.random() < 0.1) { // 10%の確率でトリム
pipeline.ltrim('list:' + tl, 0, maxlen - 1);
}
} else {
// 末尾のIDを取得
this.redisForTimelines.lindex('list:' + tl, -1).then(lastId => {
if (lastId == null || (this.idService.parse(id).date.getTime() > this.idService.parse(lastId).date.getTime())) {
this.redisForTimelines.lpush('list:' + tl, id);
} else {
Promise.resolve();
}
});
}
}
@bindThis
public get(name: string, untilId?: string | null, sinceId?: string | null) {
if (untilId && sinceId) {
return this.redisForTimelines.lrange('list:' + name, 0, -1)
.then(ids => ids.filter(id => id < untilId && id > sinceId).sort((a, b) => a > b ? -1 : 1));
} else if (untilId) {
return this.redisForTimelines.lrange('list:' + name, 0, -1)
.then(ids => ids.filter(id => id < untilId).sort((a, b) => a > b ? -1 : 1));
} else if (sinceId) {
return this.redisForTimelines.lrange('list:' + name, 0, -1)
.then(ids => ids.filter(id => id > sinceId).sort((a, b) => a < b ? -1 : 1));
} else {
return this.redisForTimelines.lrange('list:' + name, 0, -1)
.then(ids => ids.sort((a, b) => a > b ? -1 : 1));
}
}
@bindThis
public getMulti(name: string[], untilId?: string | null, sinceId?: string | null): Promise<string[][]> {
const pipeline = this.redisForTimelines.pipeline();
for (const n of name) {
pipeline.lrange('list:' + n, 0, -1);
}
return pipeline.exec().then(res => {
if (res == null) return [];
const tls = res.map(r => r[1] as string[]);
return tls.map(ids =>
(untilId && sinceId)
? ids.filter(id => id < untilId && id > sinceId).sort((a, b) => a > b ? -1 : 1)
: untilId
? ids.filter(id => id < untilId).sort((a, b) => a > b ? -1 : 1)
: sinceId
? ids.filter(id => id > sinceId).sort((a, b) => a < b ? -1 : 1)
: ids.sort((a, b) => a > b ? -1 : 1),
);
});
}
@bindThis
public purge(name: string) {
return this.redisForTimelines.del('list:' + name);
}
}