README.md

origin-storage

A same-origin storage for cross-domain access, it is based on localForage and supports IndexedDB, WebSQL and localStorage.

origin-storage uses localStorage in browsers with no IndexedDB or WebSQL support. And Safari is not supported.

Table of Contents

• Motivation
• Installation
• Usage and Example
• API
  • OriginStorage
  • OriginStorageClient

Motivation

When different Website domains need a same-origin storage container, we have to use iframe's same-origin policy Web local storage solution. localForage is an excellent storage library, it supports IndexedDB, WebSQL and localStorage, but it can't solve this problem directly.

That's why we have this library for same-origin storage based on localForage.

Installation

yarn add origin-storage

Usage and Example

• Use OriginStorage on http://localhost:9000/storage.js:

import { OriginStorage } from 'origin-storage';

const originStorage = new OriginStorage();

If you need to set up a more secure origin control, you can set targetOrigin like this.

const originStorage = new OriginStorage({
  targetOrigin: 'http://example.com',
});

• Create and host a Web page(http://localhost:9000/storage.html) containing JavaScript file storage.js.

• Use OriginStorageClient on a cross-domain page:

import { OriginStorageClient } from 'origin-storage';

const originStorageClient = new OriginStorageClient({
  uri: 'http://localhost:9000/storage.html',
});

API

OriginStorage

• new OriginStorage(options)

interface OriginStorageOptions extends IFrameTransportInternalOptions {
  /**
   * Enable read access to OriginStorage.
   */
  read?: boolean;
  /**
   * Enable write access to OriginStorage.
   */
  write?: boolean;
  /**
   * Enable broadcast data changes on OriginStorage.
   */
  broadcastChanges?: boolean;
  /**
   * Specify broadcastChannel name.
   */
  broadcastChannelName?: string;
}

OriginStorageClient

• new OriginStorageClient(options)

interface OriginStorageClientOptions extends IFrameMainTransportOptions {
  /**
   * Specify the uri of an OriginStorage container.
   */
  uri: string;
  /**
   * Set storage options for localforage.
   */
  storageOptions?: LocalForageOptions;
}

• OriginStorageClient instance methods.

interface IOriginStorageClient {
  /**
   * The callback will be called when the iframe is connected.
   */
  onConnect(callback: () => void): void;
  /**
   * The callback will be called when the storage is changed.
   */
  onChange(callback: (data: IChangeData) => void): Promise<{
    off: () => void;
    broadcastChanges: boolean;
  }>;
  /**
   * Get the value of the specified key.
   */
  getItem(key: string): Promise<any>;
  /**
   * Set the value of the specified key.
   */
  setItem(key: string, value: any): Promise<void>;
  /**
   * Remove the value of the specified key.
   */
  removeItem(key: string): Promise<void>;
  /**
   * Clear all key/value pairs in the storage.
   */
  clear(): Promise<void>;
  /**
   * Get the number of key/value pairs in the storage.
   */
  length(): Promise<number>;
  /**
   * Get the name of the nth key in the storage.
   */
  key(index: number): Promise<string>;
  /**
   * Get all keys in the storage.
   */
  keys(): Promise<string[]>;
}