🔌 Channel Provider

It exposes a global object called channelProvider that implements the EIP 1193 standard.

In the near future, it'll feature-detect if a wallet such as MetaMask has state channels support. If it does, the package does nothing; if it doesn't, it'll plug in the Embedded Wallet into a dApp.

Usage

Include the channel-provider.min.js file in your app via a script tag:

<script src="node_modules/@statechannels/channel-provider/dist/channel-provider.min.js"></script>

Then, enable the provider, passing on an URL to where the Wallet UI hosted.

This isn't final behavior. Eventually, the UI will be integrated inside a wallet like MetaMask, and the URL won't be necessary. Right now, we need this because of the usage of the .postMessage() API + CORS requirements.

window.channelProvider.mountWalletComponent('http://xstate-wallet.statechannels.org');

In order for the wallet connection to be useful, you'll want to enable it by calling .enable(). This method tells the wallet to establish a connection with the user's Web3 provider.

API

| Method | Description | | --------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------- | | mountWalletComponent(url?: string) | Configures the dApp to be able to send/receive JSON-RPC messages. | | enable() | Sends an EthereumEnable API call to the wallet. | | send<ResultType>(method: string, params?: any[]): Promise | Sends a message to the wallet using JSON-RPC and returns the result, if any. | | on(eventNameOrSubscriptionId: string, callback?: Function): void | Allows to register for events or subscriptions received from the wallet. | | off(eventNameOrSubscriptionId: string, callback?: Function): void | Allows to un-register for events or subscriptions received from the wallet. | | subscribe(subscriptionType: string, callback?: Function): Promise<string> | Allows to subscribe to an event feed, returns a subscriptionId that can be used later with .on() or .off(). | | unsubscribe(subscriptionId: string) | Removes all event listeners tied to a given subscriptionId and stops listening events on the requested feed. |