A Universal Ethereum Provider Client

Seamlessly connect to HTTP, WebSocket, IPC and Injected RPC transports in Node and the Browser!

Goals

• Follows EIP 1193 Spec
• Support all transport types (websocket, http, ipc & injected)
• Attempt connection to an array of RPC endpoints until successful connection
• Reconnect when connection is lost
• Emit helpful status updates so apps can handle changes gracefully

Install

npm install eth-provider --save

Use

const provider = require('eth-provider')
const web3 = new Web3(provider())

• By default, eth-provider will first try to discover providers injected by the environment, usually by a browser or extension
• If eth-provider fails to find an injected provider it will attempt to connect to local providers running on the user's device like Frame, Geth or Parity
• You can override these defaults by passing in your own RPC targets

const provider = require('eth-provider')
const web3 = new Web3(provider('wss://rinkeby.infura.io/ws/v3/${INFURA_ID}))

• When passing in multiple RPC targets order them by priority
• When eth-provider fails to connect to a target it will automatically attempt to connect to the next priority target
• For example ['injected', 'wss://rinkeby.infura.io/ws/v3/${INFURA_ID}'] will first try to discover injected providers and if unsuccessful connect to the Infura endpoint

const provider = require('eth-provider')
const web3 = new Web3(provider(['injected', 'wss://rinkeby.infura.io/ws/v3/${INFURA_ID}']))

• In Node and Electron you'll have access to IPC endpoints created by Geth or Parity that cannot be accessed by the Browser. You can connect to these by using the 'direct' preset, or by passing custom IPC paths

const provider = require('eth-provider')
const web3 = new Web3(provider('direct'))

Presets

• injected - Discover providers injected by environment, usually by the browser or a browser extension
  • Browser
    • ['injected']
• frame - Connect to Frame running on the user's device
  • Browser/Node/Electron
    • ['ws://127.0.0.1:1248', 'http://127.0.0.1:1248']
• direct - Connect to local Ethereum nodes running on the user's device
  • Browser
    • ['ws://127.0.0.1:8546', 'http://127.0.0.1:8545']
  • Node/Electron
    • [/* Default IPC paths for platform */, 'ws://127.0.0.1:8546', 'http://127.0.0.1:8545']
• infura - Connect to Mainnet Infura
  • Browser/Node/Electron
    • ['wss://mainnet.infura.io/ws/v3/${infuraId}', 'https://mainnet.infura.io/v3/${infuraId}']
• alchemy - Connect to Mainnet Alchemy
  • Browser/Node/Electron
    • ['wss://eth-mainnet.ws.alchemyapi.io/v2/${alchemyId}', 'https://eth-mainnet.alchemyapi.io/v2/${alchemyId}']

View all possible presets here

If you do not pass any targets, eth-provider will use default targets ['injected', 'frame'] in the Browser and ['frame', 'direct'] in Node and Electron.

Options

When creating the provider you can also pass an options object

• infuraId - Your projects Infura ID
• alchemyId - Your projects Alchemy ID
• origin - Used when connecting from outside of a browser env to declare the identity of your connection to interfaces like Frame (this currently doesn't work with HTTP connections)

provider('infura', { infuraId: '123abc' }) or provider({ origin: 'DappName', infuraId: '123abc' })

The origin setting will only be applied when a dapp is connecting to from outside of a browser env.