Wallets & Configurations
This document shows how to integrate the Flow Network programmatically with your Dapp via MetaMask.
Metamask​
Integrating additional networks into MetaMask can pose challenges for users who lack technical expertise and may lead to errors. Simplifying this process can greatly enhance user onboarding for your application. This guide demonstrates how to create a straightforward button within your frontend application to streamline the addition of the Flow network to MetaMask.
EIP-3035 & MetaMask​
EIP-3035 is an Ethereum Improvement Proposal that defines an RPC method for adding Ethereum-compatible chains to wallet applications. Since March 2021 MetaMask has implemented that EIP as part of their MetaMask Custom Networks API.
Flow Network configuration​
To add the Flow Previewnet network to Metamask, add the following network confgiuration:
_11export const PREVIEWNET_PARAMS = {_11 chainId: '0x286',_11 chainName: 'Flow',_11 rpcUrls: ['https://previewnet.evm.nodes.onflow.org'],_11 nativeCurrency: {_11 name: 'Flow',_11 symbol: 'FLOW',_11 decimals: 18,_11 },_11 blockExplorerUrls: ['https://previewnet.flowdiver.io'],_11}
Adding Flow Network​
To add this configuration to MetaMask, call the wallet_addEthereumChain
method which is exposed by the web3 provider.
_12function addFlowPreviewnet() {_12 injected.getProvider().then((provider) => {_12 provider_12 .request({_12 method: "wallet_addEthereumChain",_12 params: [PREVIEWNET_PARAMS],_12 })_12 .catch((error: any) => {_12 console.log(error)_12 })_12 })_12}
The variable, injected
, is initialized as a web3-react/injected-connector
used to interface with MetaMask APIs. Usage for other popular web frameworks is similar.
The typical usage would be to expose this button if you get errors when attempting to connect to MetaMask (i.e. Wrong Network
or Error Connecting
).
User Experience​
Users of your app will need to first approve a connection to Metamask. After doing this, if you don't detect a successful Web3 network connection, you may present a dialog asking them to add the Flow network to their wallet.
After they approve, your app will be connected to the Flow network.
By using this approach to add the Flow network to Metamask, you can avoid manual user data entry and ensure that users are ready to interact with your dApp!