grafana/public/app/core/store.ts

type StoreValue = string | number | boolean | null;

export class Store {
  get(key: string) {
    return window.localStorage[key];
  }

  set(key: string, value: StoreValue) {
    window.localStorage[key] = value;
  }

  getBool(key: string, def: boolean): boolean {
    if (def !== void 0 && !this.exists(key)) {
      return def;
    }
    return window.localStorage[key] === 'true';
  }

  getObject<T = unknown>(key: string): T | undefined;
  getObject<T = unknown>(key: string, def: T): T;
  getObject<T = unknown>(key: string, def?: T) {
    let ret = def;
    if (this.exists(key)) {
      const json = window.localStorage[key];
      try {
        ret = JSON.parse(json);
      } catch (error) {
        console.error(`Error parsing store object: ${key}. Returning default: ${def}. [${error}]`);
      }
    }
    return ret;
  }

  /* Returns true when successfully stored, throws error if not successfully stored */
  setObject(key: string, value: any) {
    let json;
    try {
      json = JSON.stringify(value);
    } catch (error) {
      throw new Error(`Could not stringify object: ${key}. [${error}]`);
    }
    try {
      this.set(key, json);
    } catch (error) {
      // Likely hitting storage quota
      const errorToThrow = new Error(`Could not save item in localStorage: ${key}. [${error}]`);
      if (error instanceof Error) {
        errorToThrow.name = error.name;
      }
      throw errorToThrow;
    }
    return true;
  }

  exists(key: string) {
    return window.localStorage[key] !== void 0;
  }

  delete(key: string) {
    window.localStorage.removeItem(key);
  }
}

const store = new Store();
export default store;