Use MetaMask SDK with Node.js

Import MetaMask SDK into your Node.js dapp to enable your users to easily connect to the MetaMask browser extension and MetaMask Mobile. The SDK for Node.js has the same prerequisites as for standard JavaScript.

Steps

1. Install the SDK

In your project directory, install the SDK using Yarn or npm:

yarn add @metamask/sdk

or

npm i @metamask/sdk

2. Import the SDK

In your project script, add the following to import the SDK:

index.js

import { MetaMaskSDK } from "@metamask/sdk"

3. Instantiate the SDK

Instantiate the SDK using any options:

index.js

const MMSDK = new MetaMaskSDK({
  dappMetadata: {
    name: "Node.js dapp",
  },
  infuraAPIKey: process.env.INFURA_API_KEY,
  // Other options.
})

• Use dappMetadata to display information about your dapp in the MetaMask connection modal.
• Use infuraAPIKey to make read-only RPC requests from your dapp.

4. Use the SDK

Use the SDK by calling any provider API methods. Always call eth_requestAccounts using request() first, since it prompts the installation or connection popup to appear.

const accounts = await sdk.connect();
console.log("connect request accounts", accounts);

// You can also access the Ethereum provider object.
const provider = MMSDK.getProvider()
provider.request({ method: "eth_requestAccounts", params: [] })

You can also call the SDK's connectAndSign method, and batch multiple JSON-RPC requests using the metamask_batch method.

Example

You can copy the full Node.js example to get started:

index.js

import { MetaMaskSDK } from "@metamask/sdk"

const MMSDK = new MetaMaskSDK({
  dappMetadata: {
    name: "Example Node.js Dapp",
  },
  infuraAPIKey: process.env.INFURA_API_KEY,
  // Other options.
})

const accounts = await MMSDK.connect()
const provider = MMSDK.getProvider()
provider.request({ method: "eth_accounts", params: [] })

See the example Node.js dapp in the JavaScript SDK GitHub repository for advanced use cases.