joincolony/node-metamask

🦊 Connect to MetaMask from node.js

node-metamask

Connect Node.js to MetaMask.

"Why would I ever want to do that?" - Sometimes you might have scripts or libraries that run in Node and require signed transactions that you would like to use MetaMask for (instead of dealing with private keys). This tool functions as a web3 provider that can be used with pretty much any MetaMask instance remotely. Please, only use this package locally to prevent PITM attacks (if you're brave enough to try it on mainnet).

Sounds crazy? It probably is. Also highly experimental. Please use with caution.

Install

yarn add node-metamask

Usage

const MetaMaskConnector = require('node-metamask');
const connector = new MetaMaskConnector({
  port: 3333, // this is the default port
  onConnect() { console.log('MetaMask client connected') }, // Function to run when MetaMask is connected (optional)
});

connector.start().then(() => {
  // Now go to http://localhost:3333 in your MetaMask enabled web browser.
  const web3 = new Web3(connector.getProvider());
  // Use web3 as you would normally do. Sign transactions in the browser.
});

When you're done with your MetaMask business, run the following code to clean up:

connector.stop();

Disclaimer

As I said, this is highly experimental. Tested only with web3 v1.0 (in node) and web3 0.20.3 (MetaMask, in the browser). Also it might not work with all functions supported by web3.

Contribute

Please report any bugs you find so we can improve this.

• Contributing

node-metamask's Issues

Metamask crashes after the connector starts

I'm trying to authenticate transactions using metamask. I execute the following code but once I connect to page localhost:3333, MetaMask plugin crashes. It tries to show me the transaction notification but then goes blank.

async function connectToMetamask() {
  const connector = new MetaMaskConnector({
    port: 3333,
    onConnect() {
      console.log('MetaMask client connected')
    },
  });

  // Now go to http://localhost:3333 in your MetaMask enabled web browser.
  console.log("Go to http://localhost:3333");
  await connector.start();
  const web3 = new Web3(connector.getProvider());
  // Use web3 as you would normally do. Sign transactions in the browser.
  CampaignContract.setProvider(connector.getProvider());
}

Use with ColonyNetworkClient

Hello, I'm trying to use this with ColonyNetworkClient to create a colony on the rinkeby network with my MetaMask.

You can see what I have so far here: https://github.com/Pioneercoinio/PioneerColony/blob/MetaMaskClient/src/metamask_client.js

It seems that the contracts are not being loaded from rinkeby. The error I get is

(node:85249) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'send' of undefined
    at _callee$ (/github/pioneercoinio/PioneerColony/src/pioneercolony.js:7:40)

Any idea on what I'm missing?

Does it really needs MetaMask installed on browser?

Could it be used on Electron app without need of MetaMask installed?

Errors using package with the latest version of web3

Description

node-metamask currently does not support the latest beta release of the web3 package. I received the following error running node-metamask with web3 version 1.0.0-beta.51:

Error: method.split is not a function

I was able to successfully run node-metamask with web3 version 1.0.0-beta.35. I have not yet tried to run it with any other versions between beta.35 and beta.51.

MetaMask no longer injects web3.

Description

According to their docs:
https://docs.metamask.io/guide/provider-migration.html#replacing-window-web3

"start" promise never resolved?

I'm running the latest version of MetaMask on my GoogleChrome on OSX and when i run the javascript example on my node ( version 9 ), the "start" promise is never resolved.

It just hangs in there and no callbacks are ever called.

What i'm a doing wrong? ( I'm running exactly the readme file example )