notesnook/packages/core/database/cached-collection.js

import Storage from "./storage";
import HyperSearch from "hypersearch";
import { getSchema } from "./schemas";
import PersistentCachedMap from "./persistentcachedmap";
import sort from "fast-sort";
import IndexedCollection from "./indexed-collection";

export default class CachedCollection extends IndexedCollection {
  async init() {
    const index = new PersistentCachedMap(`${this.type}Index`, this.storage);
    const store = new PersistentCachedMap(`${this.type}Store`, this.storage);
    await index.init();
    await store.init();
    this.search = new HyperSearch({
      schema: getSchema(this.type),
      tokenizer: "forward",
      index,
      store,
    });
  }

  exists(id) {
    const item = this.getItem(id);
    return item && !item.deleted;
  }

  getRaw() {
    return Array.from(this.search.getAllDocs());
  }

  getItems(sortFn = (u) => u.dateCreated) {
    let items = [];
    this.search.options.store.forEach((value) => {
      if (!value || value.deleted) return;
      items[items.length] = value;
    });
    return sort(items).desc(sortFn);
  }
}