MemoryCache Typescript https://codesandbox.io/s/zen-silence-vcukn?file=/src/index.ts:0-293

index.ts

import MemoryCache from "./MemoryCache";

const posts = [
  {
    id: 1,
    title: "Hello World"
  },
  {
    id: 2,
    title: "Another Hello";
  }
];

const Cache = new MemoryCache();


(async () => {
  await Cache.setItem("posts", posts);
  console.log(await Cache.getItem('posts'));
})();

MemoryCache.ts

class MemoryCache {
  memoryStore: Map<string, string>;
  constructor() {
    this.memoryStore = new Map();
  }
  async setItem(key: string, value: string): Promise<void> {
    this.memoryStore.set(key, value);
  }

  async getAllKeys(): Promise<string[]> {
    return Array.from(this.memoryStore.keys());
  }

  async getItem(key: string): Promise<string | null> {
    if (this.memoryStore.has(key)) {
      return this.memoryStore.get(key) as string;
    } else {
      return null;
    }
  }

  async multiGet(keys: string[]): Promise<any[][]> {
    const results: any[][] = [];
    for (const key of keys) {
      results.push([key, this.getItem(key)]);
    }

    return results;
  }

  async multiRemove(keys: string[]): Promise<void> {
    for (const key of keys) {
      this.memoryStore.delete(key);
    }
  }

  async removeItem(key: string): Promise<void> {
    this.memoryStore.delete(key);
  }

  async clearItem(): Promise<void> {
    this.memoryStore.clear();
  }
}

export default MemoryCache;