Add TrendsWorker for tracking/querying trending tags with a Web Worker

src/trends.ts

@@ -1,125 +0,0 @@
-import { Sqlite } from '@/deps.ts';
-import { hashtagSchema } from '@/schema.ts';
-import { nostrIdSchema } from '@/schemas/nostr.ts';
-import { Time } from '@/utils.ts';
-import { generateDateRange } from '@/utils/time.ts';
-
-interface GetTrendingTagsOpts {
-  since: Date;
-  until: Date;
-  limit?: number;
-  threshold?: number;
-}
-
-interface GetTagHistoryOpts {
-  tag: string;
-  since: Date;
-  until: Date;
-  limit?: number;
-  offset?: number;
-}
-
-class TrendsDB {
-  #db: Sqlite;
-
-  constructor(db: Sqlite) {
-    this.#db = db;
-
-    this.#db.execute(`
-      CREATE TABLE IF NOT EXISTS tag_usages (
-        tag TEXT NOT NULL COLLATE NOCASE,
-        pubkey8 TEXT NOT NULL,
-        inserted_at DATETIME NOT NULL
-      );
-
-      CREATE INDEX IF NOT EXISTS idx_time_tag ON tag_usages(inserted_at, tag);
-    `);
-
-    const cleanup = () => {
-      console.info('Cleaning up old tag usages...');
-      const lastWeek = new Date(new Date().getTime() - Time.days(7));
-      this.cleanupTagUsages(lastWeek);
-    };
-
-    setInterval(cleanup, Time.hours(1));
-    cleanup();
-  }
-
-  /** Gets the most used hashtags between the date range. */
-  getTrendingTags({ since, until, limit = 10, threshold = 3 }: GetTrendingTagsOpts) {
-    return this.#db.query<string[]>(
-      `
-      SELECT tag, COUNT(DISTINCT pubkey8), COUNT(*)
-        FROM tag_usages
-        WHERE inserted_at >= ? AND inserted_at < ?
-        GROUP BY tag
-        HAVING COUNT(DISTINCT pubkey8) >= ?
-        ORDER BY COUNT(DISTINCT pubkey8)
-        DESC LIMIT ?;
-    `,
-      [since, until, threshold, limit],
-    ).map((row) => ({
-      name: row[0],
-      accounts: Number(row[1]),
-      uses: Number(row[2]),
-    }));
-  }
-
-  /**
-   * Gets the tag usage count for a specific tag.
-   * It returns an array with counts for each date between the range.
-   */
-  getTagHistory({ tag, since, until, limit = 7, offset = 0 }: GetTagHistoryOpts) {
-    const result = this.#db.query<string[]>(
-      `
-      SELECT date(inserted_at), COUNT(DISTINCT pubkey8), COUNT(*)
-        FROM tag_usages
-        WHERE tag = ? AND inserted_at >= ? AND inserted_at < ?
-        GROUP BY date(inserted_at)
-        ORDER BY date(inserted_at) DESC
-        LIMIT ?
-        OFFSET ?;
-    `,
-      [tag, since, until, limit, offset],
-    ).map((row) => ({
-      day: new Date(row[0]),
-      accounts: Number(row[1]),
-      uses: Number(row[2]),
-    }));
-
-    /** Full date range between `since` and `until`. */
-    const dateRange = generateDateRange(
-      new Date(since.getTime() + Time.days(1)),
-      new Date(until.getTime() - Time.days(offset)),
-    ).reverse();
-
-    // Fill in missing dates with 0 usages.
-    return dateRange.map((day) => {
-      const data = result.find((item) => item.day.getTime() === day.getTime());
-      return data || { day, accounts: 0, uses: 0 };
-    });
-  }
-
-  addTagUsages(pubkey: string, hashtags: string[], date = new Date()): void {
-    const pubkey8 = nostrIdSchema.parse(pubkey).substring(0, 8);
-    const tags = hashtagSchema.array().min(1).parse(hashtags);
-
-    this.#db.query(
-      'INSERT INTO tag_usages (tag, pubkey8, inserted_at) VALUES ' + tags.map(() => '(?, ?, ?)').join(', '),
-      tags.map((tag) => [tag, pubkey8, date]).flat(),
-    );
-  }
-
-  cleanupTagUsages(until: Date): void {
-    this.#db.query(
-      'DELETE FROM tag_usages WHERE inserted_at < ?',
-      [until],
-    );
-  }
-}
-
-const trends = new TrendsDB(
-  new Sqlite('data/trends.sqlite3'),
-);
-
-export { trends, TrendsDB };