**Fork from https://github.com/blocknative/web3-onboard＊＊

@web3-onboard/core

This is the core package that contains all of the UI and logic to be able to seamlessly connect user's wallets to your app and track the state of those wallets. Onboard no longer contains any wallet specific code, so wallets need to be passed in upon initialization.

Installation

Install the core module:

npm i @web3-onboard/core

If you would like to support all wallets, then you can install all of the wallet modules:

npm i @web3-onboard/injected-wallets @web3-onboard/ledger @web3-onboard/trezor @web3-onboard/keepkey @web3-onboard/walletconnect @web3-onboard/walletlink @web3-onboard/torus @web3-onboard/portis @web3-onboard/mew @web3-onboard/gnosis @web3-onboard/magic @web3-onboard/fortmatic

Note:

- MEW wallet currently fails to install on M1 macs
- All wallet modules (except for injected-wallets) require extra dependencies and may require polyfilling the node built in modules for the browser. See the Build Environments section for more info
- If using React you may be interested in checking out the React Hooks package here - https://www.npmjs.com/package/@web3-onboard/react

Initialization

Onboard needs to be initialized with an options object before the API can be used:

``typescript
type InitOptions {
wallets: WalletInit[]
chains: Chain[]
appMetadata?: AppMetadata
i18n?: i18nOptions
accountCenter?: AccountCenterOptions
}
`

$3

wallets
An array of wallet modules that you would like to be presented to the user to select from when connecting a wallet. A wallet module is an abstraction that allows for easy interaction without needing to know the specifics of how that wallet works and are separate packages that can be included. A list of wallet module packages that can be installed can be found here.

chains
An array of Chains that your app supports:

`typescript
type Chain = {
id: ChainId // hex encoded string, eg '0x1' for Ethereum Mainnet
namespace?: 'evm' // string indicating chain namespace. Defaults to 'evm' but will allow other chain namespaces in the future
rpcUrl: string // used for network requests
label: string // used for display, eg Ethereum Mainnet
token: TokenSymbol // the native token symbol, eg ETH, BNB, MATIC
color?: string // the color used to represent the chain and will be used as a background for the icon
icon?: string // the icon to represent the chain
}
`

appMetadata
An object that defines your app:

`typescript
type AppMetadata = {
// app name
name: string
// SVG icon string, with height or width (whichever is larger) set to 100% or a valid image URL
// note: if using an emoji make sure to send base64 string
icon: string
// Optional wide format logo (ie icon and text) to be displayed in the sidebar of connect modal. Defaults to icon if not provided
logo?: string
// description of app
description?: string
// url to a getting started guide for app
gettingStartedGuide?: string
// url that points to more information about app
explore?: string
// if your app only supports injected wallets and when no injected wallets detected, recommend the user to install some
recommendedInjectedWallets?: RecommendedInjectedWallets[]
}

type RecommendedInjectedWallets = {
name: string // display name
url: string // link to download wallet
}
`

i18n
An object that defines the display text for different locales. Can also be used to override the default text. To override the default text, pass in a object for the en locale.

`typescript
type Locale = string // eg 'en', 'es'
type i18nOptions = Record
`

To see a list of all of the text values that can be internationalized or replaced, check out the default en file.
Onboard is using the ICU syntax for formatting under the hood.

accountCenter
An object that defines whether the account center UI is enabled and it's position on the screen. Currently the account center is disabled for mobile devices, so only desktop options are available.

`typescript
type AccountCenterOptions = {
desktop: {
position?: AccountCenterPosition // default: 'topRight'
enabled?: AccountCenter['enabled'] // default: true
}
}

type AccountCenter = {
enabled: boolean
position: AccountCenterPosition
expanded: boolean
}

type AccountCenterPosition =
| 'topRight'
| 'bottomRight'
| 'bottomLeft'
| 'topLeft'
`

$3

Putting it all together, here is an example initialization with the injected wallet modules:

`javascript
import Onboard from '@web3-onboard/core'
import injectedModule from '@web3-onboard/injected-wallets'

const injected = injectedModule()

const onboard = Onboard({
wallets: [injected],
chains: [
{
id: '0x1',
token: 'ETH',
label: 'Ethereum Mainnet',
rpcUrl: https://mainnet.infura.io/v3/${INFURA_ID}
},
{
id: '0x3',
token: 'tROP',
label: 'Ethereum Ropsten Testnet',
rpcUrl: https://ropsten.infura.io/v3/${INFURA_ID}
},
{
id: '0x4',
token: 'rETH',
label: 'Ethereum Rinkeby Testnet',
rpcUrl: https://rinkeby.infura.io/v3/${INFURA_ID}
},
{
id: '0x38',
token: 'BNB',
label: 'Binance Smart Chain',
rpcUrl: 'https://bsc-dataseed.binance.org/'
},
{
id: '0x89',
token: 'MATIC',
label: 'Matic Mainnet',
rpcUrl: 'https://matic-mainnet.chainstacklabs.com'
},
{
id: '0xfa',
token: 'FTM',
label: 'Fantom Mainnet',
rpcUrl: 'https://rpc.ftm.tools/'
}
],
appMetadata: {
name: 'Token Swap',
icon: myIcon, // svg string icon
logo: myLogo, // svg string logo
description: 'Swap tokens for other tokens',
recommendedInjectedWallets: [
{ name: 'MetaMask', url: 'https://metamask.io' },
{ name: 'Coinbase', url: 'https://wallet.coinbase.com/' }
]
}
i18n: {
en: {
connect: {
selectingWallet: {
header: 'custom text header'
}
}
}
}
})
`

Connecting a Wallet

To initiate a user to select and connect a wallet you can call the connectWallet function on an initialized Onboard instance. It will return a Promise that will resolve when the user either successfully connects a wallet, or when they dismiss the UI. The resolved value from the promise will be the latest state of the wallets array. The order of the wallets array is last to first, so the most recently selected wallet will be the first item in the array and can be thought of as the "primary wallet". If no wallet was selected, then the wallets array will have the same state as it had before calling connectWallet.

$3

`javascript
async function connectWallet() {
const wallets = await onboard.connectWallet()
console.log(wallets)
}

connectWallet()
`

$3

A common UX pattern is to remember the wallet(s) that a user has previously connected by storing them in localStorage and then automatically selecting them for the user next time they visit your app.
You could enable this in your app by first syncing the wallets array to localStorage:

`javascript
const walletsSub = onboard.state.select('wallets')
const { unsubscribe } = walletsSub.subscribe(wallets => {
const connectedWallets = wallets.map(({ label }) => label)
window.localStorage.setItem(
'connectedWallets',
JSON.stringify(connectedWallets)
)
})

// Don't forget to unsubscribe when your app or component un mounts to prevent memory leaks
// unsubscribe()
`

Now that you have the most recent wallets connected saved in local storage, you can auto select those wallet(s) when your app loads:

`javascript
const previouslyConnectedWallets = JSON.parse(
window.localStorage.getItem('connectedWallets')
)

if (previouslyConnectedWallets) {
// Connect the most recently connected wallet (first in the array)
await onboard.connectWallet({ autoSelect: previouslyConnectedWallets[0] })

// You can also auto connect "silently" and disable all onboard modals to avoid them flashing on page load
await onboard.connectWallet({
autoSelect: { label: previouslyConnectedWallets[0], disableModals: true }
})

// OR - loop through and initiate connection for all previously connected wallets
// note: This UX might not be great as the user may need to login to each wallet one after the other
// for (walletLabel in previouslyConnectedWallets) {
// await onboard.connectWallet({ autoSelect: walletLabel })
// }
}
`

Disconnecting a Wallet

A wallet can be disconnected, which will cleanup any background operations the wallet may be doing and will also remove it from the Onboard wallets array:

`javascript
// disconnect the first wallet in the wallets array
const [primaryWallet] = onboard.state.get().wallets
await onboard.disconnectWallet({ label: primaryWallet.label })
`

The disconnectWallet method takes the wallet.label value and returns a Promise that resolves to the current state of the wallets array.

State

Onboard currently keeps track of the following state:

- wallets: The wallets connected to Onboard
- chains: The chains that Onboard has been initialized with
- accountCenter: The current state of the account center UI
- walletModules: The wallet modules that are currently set and will be rendered in the wallet selection modal

`typescript
type AppState = {
wallets: WalletState[]
chains: Chain[]
accountCenter: AccountCenter
walletModules: WalletModule[]
}

type Chain {
namespace?: 'evm'
id: ChainId
rpcUrl: string
label: string
token: TokenSymbol
color?: string
icon?: string
}

type WalletState = {
label: string
icon: string
provider: EIP1193Provider
accounts: Account[]
chains: ConnectedChain[]
instance?: unknown
}

type Account = {
address: string
ens: {
name?: string
avatar?: string
contentHash?: string
getText?: (key: string) => Promise
}
balance: Record
}

type ConnectedChain = {
namespace: 'evm'
id: ChainId
}

type ChainId = string
type TokenSymbol = string

type AccountCenter = {
enabled: boolean
position: AccountCenterPosition
expanded: boolean
}

type AccountCenterPosition =
| 'topRight'
| 'bottomRight'
| 'bottomLeft'
| 'topLeft'

type WalletModule {
label: string
getIcon: () => Promise
getInterface: (helpers: GetInterfaceHelpers) => Promise
}
`

$3

The current state of Onboard can be accessed at any time using the state.get() method:

`javascript
const currentState = onboard.state.get()
`

$3

State can also be subscribed to using the state.select() method. The select method will return an RXJS Observable. Understanding of RXJS observables is not necessary to subscribe to state updates, but allows for composable functionality if wanted. The key point to understand is that if you subscribe for updates, remember to unsubscribe when you are finished to prevent memory leaks.

To subscribe to all state updates, call the select method with no arguments:

`javascript
const state = onboard.state.select()
const { unsubscribe } = state.subscribe(update =>
console.log('state update: ', update)
)

// remember to unsubscribe when updates are no longer needed
// unsubscribe()
`

Specific top level slices of state can be subscribed to. For example you may want to just subscribe to receive updates to the wallets array only:

`javascript
const wallets = onboard.state.select('wallets')
const { unsubscribe } = wallets.subscribe(update =>
console.log('wallets update: ', update)
)

// unsubscribe when updates are no longer needed
unsubscribe()
`

$3

A limited subset of internal actions are exposed to update the Onboard state.

setWalletModules
For updating the wallets that are displayed in the wallet selection modal. This can be used if the wallets you want to support is conditional on another user action within your app. The setWalletModules action is called with an updated array of wallets (the same wallets that are passed in on initialization)

`typescript
import Onboard from '@web3-onboard/core'
import injectedModule from '@web3-onboard/injected-wallets'
import ledgerModule from '@web3-onboard/ledger'
import trezorModule from '@web3-onboard/trezor'

const injected = injectedModule()
const ledger = ledgerModule()
const trezor = trezorModule({
email: '',
appUrl: ''
})

// initialize with injected and hardware wallets
const onboard = Onboard({
wallets: [injected, trezor, ledger],
chains: [
{
id: '0x1',
token: 'ETH',
label: 'Ethereum Mainnet',
rpcUrl: https://mainnet.infura.io/v3/${INFURA_ID}
}
]
})

// then after a user action, you may decide to only display hardware wallets on the next call to onboard.connectWallet
onboard.state.actions.setWalletModules([ledger, trezor])
`

Setting the User's Chain/Network

When initializing Onboard you define a list of chains/networks that your app supports. If you would like to prompt the user to switch to one of those chains, you can use the setChain method on an initialized instance of Onboard:

`typescript
type SetChain = (options: SetChainOptions) => Promise
type SetChainOptions = {
chainId: string // hex encoded string
chainNamespace?: 'evm' // defaults to 'evm' (currently the only valid value, but will add more in future updates)
wallet?: string // the wallet.label of the wallet to set chain
}

const success = await onboard.setChain({ chainId: '0x89' })
`

The setChain methods takes an options object with a chainId property hex encoded string for the chain id to switch to. The chain id must be one of the chains that Onboard was initialized with. If the wallet supports programatically adding and switching the chain, then the user will be prompted to do so, if not, then a modal will be displayed indicating to the user that they need to switch chains to continue. The setChain method returns a promise that resolves when either the user has confirmed the chain switch, or has dismissed the modal and resolves with a boolean indicating if the switch network was successful or not. The setChain method will by default switch the first wallet (the most recently connected) in the wallets array. A specific wallet can be targeted by passing in the wallet.label in the options object as the wallet parameter.

Custom Styling

The Onboard styles can customized via CSS variables. The following properties and their default properties can be customized by adding these variables to the :root in your CSS file:

`css
:root {
/ CUSTOMIZE THE COLOR PALLETTE /
--onboard-white: white;
--onboard-black: black;
--onboard-primary-1: #2f80ed;
--onboard-primary-100: #eff1fc;
--onboard-primary-200: #d0d4f7;
--onboard-primary-300: #b1b8f2;
--onboard-primary-400: #929bed;
--onboard-primary-500: #6370e5;
--onboard-primary-600: #454ea0;
--onboard-primary-700: #323873;
--onboard-gray-100: #ebebed;
--onboard-gray-200: #c2c4c9;
--onboard-gray-300: #999ca5;
--onboard-gray-400: #707481;
--onboard-gray-500: #33394b;
--onboard-gray-600: #242835;
--onboard-gray-700: #1a1d26;
--onboard-success-100: #d1fae3;
--onboard-success-200: #baf7d5;
--onboard-success-300: #a4f4c6;
--onboard-success-400: #8df2b8;
--onboard-success-500: #5aec99;
--onboard-success-600: #18ce66;
--onboard-success-700: #129b4d;
--onboard-danger-100: #ffe5e6;
--onboard-danger-200: #ffcccc;
--onboard-danger-300: #ffb3b3;
--onboard-danger-400: #ff8080;
--onboard-danger-500: #ff4f4f;
--onboard-danger-600: #cc0000;
--onboard-danger-700: #660000;
--onboard-warning-100: #ffefcc;
--onboard-warning-200: #ffe7b3;
--onboard-warning-300: #ffd780;
--onboard-warning-400: #ffc74c;
--onboard-warning-500: #ffaf00;
--onboard-warning-600: #cc8c00;
--onboard-warning-700: #664600;

/ CUSTOMIZE SECTIONS OF THE CONNECT MODAL /
--onboard-connect-content-width
--onboard-connect-content-height
--onboard-wallet-columns
--onboard-connect-sidebar-background
--onboard-connect-sidebar-color
--onboard-connect-sidebar-progress-background
--onboard-connect-sidebar-progress-color
--onboard-connect-header-background
--onboard-connect-header-color
--onboard-main-scroll-container-background
--onboard-link-color
--onboard-close-button-background
--onboard-close-button-color
--onboard-checkbox-background
--onboard-checkbox-color
--onboard-wallet-button-background
--onboard-wallet-button-background-hover
--onboard-wallet-button-color
--onboard-wallet-button-border-color
--onboard-wallet-app-icon-border-color

/ FONTS /
--onboard-font-family-normal: Sofia Pro;
--onboard-font-family-semibold: Sofia Pro Semibold;
--onboard-font-family-light: Sofia Pro Light;

--onboard-font-size-1: 3rem;
--onboard-font-size-2: 2.25rem;
--onboard-font-size-3: 1.5rem;
--onboard-font-size-4: 1.25rem;
--onboard-font-size-5: 1rem;
--onboard-font-size-6: 0.875rem;
--onboard-font-size-7: 0.75rem;

/ SPACING /
--onboard-spacing-1: 3rem;
--onboard-spacing-2: 2rem;
--onboard-spacing-3: 1.5rem;
--onboard-spacing-4: 1rem;
--onboard-spacing-5: 0.5rem;

/ SHADOWS /
--onboard-shadow-1: 0px 4px 12px rgba(0, 0, 0, 0.1);
--onboard-shadow-2: inset 0px -1px 0px rgba(0, 0, 0, 0.1);

/ MAIN MODAL POSITIONING /
--onboard-modal-z-index
--onboard-modal-top
--onboard-modal-bottom
--onboard-modal-right
--onboard-modal-left

/ HD WALLET ACCOUNT SELECT MODAL POSITIONING /
--onboard-account-select-modal-z-index
--onboard-account-select-modal-top
--onboard-account-select-modal-bottom
--onboard-account-select-modal-right
--onboard-account-select-modal-left

/ MAGIC WALLET MODAL POSITIONING /
--onboard-login-modal-z-index
--onboard-login-modal-top
--onboard-login-modal-bottom
--onboard-login-modal-right
--onboard-login-modal-left


/ HARDWARE WALLET STYLES /
/ if not set will fallback to variables with --onboard prefix shown above */

/ COLORS /
--account-select-modal-white: white;
--account-select-modal-black: black;
--account-select-modal-primary-100: #eff1fc;
--account-select-modal-primary-200: #d0d4f7;
--account-select-modal-primary-300: #b1b8f2;
--account-select-modal-primary-500: #6370e5;
--account-select-modal-primary-600: #454ea0;
--account-select-modal-gray-100: #ebebed;
--account-select-modal-gray-200: #c2c4c9;
--account-select-modal-gray-300: #999ca5;
--account-select-modal-gray-500: #33394b;
--account-select-modal-gray-700: #1a1d26;
--account-select-modal-danger-500: #ff4f4f;

/ FONTS /
--account-select-modal-font-family-normal: Sofia Pro;
--account-select-modal-font-family-light: Sofia Pro Light;
--account-select-modal-font-size-5: 1rem;
--account-select-modal-font-size-7: .75rem;
--account-select-modal-font-line-height-1: 24px;

/ SPACING /
--account-select-modal-margin-4: 1rem;
--account-select-modal-margin-5: 0.5rem;
}
`

Build Environments

Many of the wallet modules require dependencies that are not normally included in browser builds (namely the node builtin modules such as crypto, buffer, util etc). If you are having build issues you can try the following bundler configs to resolve these dependency issues:

$3

Everything should just work since the node built-ins are automatically bundled in v4

$3

You'll need to add some dev dependencies with the following command:

npm i --save-dev assert buffer crypto-browserify stream-http https-browserify os-browserify process stream-browserify util

Then add the following to your webpack.config.js file:

`javascript
const webpack = require('webpack')

module.exports = {
resolve: {
alias: {
assert: 'assert',
buffer: 'buffer',
crypto: 'crypto-browserify',
http: 'stream-http',
https: 'https-browserify',
os: 'os-browserify/browser',
process: 'process/browser',
stream: 'stream-browserify',
util: 'util'
}
},
experiments: {
asyncWebAssembly: true
},
plugins: [
new webpack.ProvidePlugin({
process: 'process/browser',
Buffer: ['buffer', 'Buffer']
})
]
}
`

#### If using create-react-app

CRACO provides an easy way to override webpack config which is obfuscated in Create React App built applications.

The above webpack 5 example can be used in the craco.config.js file at the root level in this case.

$3

Add the following dev dependencies:

npm i --save-dev rollup-plugin-polyfill-node

Then add the following to your svelte.config.js file:

`javascript
import adapter from '@sveltejs/adapter-auto'
import preprocess from 'svelte-preprocess'
import nodePolyfills from 'rollup-plugin-polyfill-node'

const MODE = process.env.NODE_ENV
const development = MODE === 'development'

/* @type {import('@sveltejs/kit').Config} /
const config = {
preprocess: preprocess(),
kit: {
adapter: adapter(),
vite: {
plugins: [
development &&
nodePolyfills({
include: [
'node_modules/*/.js',
new RegExp('node_modules/.vite/.*js')
],
http: true,
crypto: true
})
],
resolve: {
alias: {
crypto: 'crypto-browserify',
stream: 'stream-browserify',
assert: 'assert'
}
},
build: {
rollupOptions: {
plugins: [nodePolyfills({ crypto: true, http: true })]
},
commonjsOptions: {
transformMixedEsModules: true
}
}
}
}
}

export default config
`

$3

Add the following dev dependencies:

npm i --save-dev rollup-plugin-polyfill-node

Then add the following to your vite.config.js file:

`javascript
import nodePolyfills from 'rollup-plugin-polyfill-node'

const MODE = process.env.NODE_ENV
const development = MODE === 'development'

export default {
// other config options
plugins: [
development &&
nodePolyfills({
include: [
'node_modules/*/.js',
new RegExp('node_modules/.vite/.*js')
],
http: true,
crypto: true
})
],
resolve: {
alias: {
crypto: 'crypto-browserify',
stream: 'stream-browserify',
assert: 'assert'
}
},
build: {
rollupOptions: {
plugins: [nodePolyfills({ crypto: true, http: true })]
},
commonjsOptions: {
transformMixedEsModules: true
}
}
}
`

$3

Add the following to your nuxt.config.js:

`javascript
build: {
standalone: true,
}
``