chernodub/ngx-lss

Reactive `localStorage` adapter for Angular applications 🎆

ngx-lss

ngx-lss is an angular library that provides a reactive adapter for localStorage API

Features

• 🎆 Provides Observable API
• 👀 Allows watching changes made in other tabs
• 🐣 Easily adaptable and replaceable (3 simple methods: save, get, remove)
• 🔬 Fully tested with jasmine

Installation

npm i ngx-lss

Setting up

1. Import NgxLocalStorageModule to root module of your app

import { NgxLocalStorageModule } from 'ngx-lss';

@NgModule({
  // ...
  imports: [
    // ...
    NgxLocalStorageModule.forRoot(),
  ]
})
export class AppModule { }

2. Inject the service in your injectable class

import { Component } from '@angular/core';
import { NgxLocalStorageService } from 'ngx-lss';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  public constructor(
    private readonly NgxLocalStorageService: NgxLocalStorageService,
 ) {
    // ...
  }
}

Usage examples

Abstracting the service in a domain specific storage

💡 This is a recommended way to use the ngx-lss in your applications. It allows you to clearly separate the logic of working with the local storage from the business logic of your application. Also, this way, you can easily replace the library with another storage or your own implementation.

import { Injectable } from '@angular/core';
import { NgxLocalStorageService } from 'ngx-lss';
import { map, Observable } from 'rxjs';

import { UserSecret } from '../models/user-secret';


const USER_SECRET_STORAGE_KEY = 'user';

@Injectable({ providedIn: 'root' })
export class UserSecretStorageService {
  /** Credential secret of the current user. */
  public readonly currentSecret$: Observable<UserSecret | null>;

  public constructor(
    private readonly storageService: NgxLocalStorageService,
  ) {
    this.currentSecret$ = this.storageService.get<UserSecret>(USER_SECRET_STORAGE_KEY);
  }

  /**
   * Saves secret to the current storage.
   * @param secret Secret to save.
   */
  public saveSecret(
    secret: UserSecret,
  ): Observable<UserSecret> {
    return this.storageService.save(USER_SECRET_STORAGE_KEY, secret).pipe(map(() => secret));
  }

  /** Removes current secret. */
  public removeSecret(): Observable<void> {
    return this.storageService.remove(USER_SECRET_STORAGE_KEY);
  }
}

Accessing the storage API directly from a component

import { Component } from '@angular/core';
import { NgxLocalStorageService } from 'ngx-lss';

const COUNTER_KEY = 'counter';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {

  /** Clicks counter. */
  public readonly counter$: Observable<number | null>;

  public constructor(
    private readonly storage: NgxLocalStorageService,
  ) {
    this.counter$ = this.storage.get<number>(COUNTER_KEY);
  }

  public onUserClick(): void {
    this.counter$.pipe(
      first(),
      map(counter => counter ?? 0),
      switchMap(counter => this.storage.save(COUNTER_KEY, counter + 1)),
    ).subscribe();
  }
}