Polkadot
Integrate Polkadot and Substrate-based chains using OneKey’s provider. Access via window.$onekey.polkadot or the Polkadot.js extension API.
OneKey implements the Polkadot.js extension interface, ensuring compatibility with all Substrate dApps.
Quick Links
Provider Detection
// OneKey registers as a Polkadot.js extension
const provider = window.$onekey?.polkadot
// Or use the standard web3Enable API
import { web3Enable, web3Accounts } from '@polkadot/extension-dapp'Quick Start
Enable Extension
// Using OneKey provider directly
const enabled = await provider.web3Enable('My dApp')
if (enabled) {
const accounts = await provider.web3Accounts()
console.log('Accounts:', accounts)
}Using Polkadot.js Extension API (Recommended)
import { web3Enable, web3Accounts } from '@polkadot/extension-dapp'
// Enable all extensions (including OneKey)
const extensions = await web3Enable('My dApp')
if (extensions.length === 0) {
throw new Error('No extension found')
}
// Get all accounts
const allAccounts = await web3Accounts()
console.log('Accounts:', allAccounts)Account Management
Get Accounts
const accounts = await provider.web3Accounts()
accounts.forEach(account => {
console.log({
address: account.address, // Substrate address
name: account.name, // Account name
type: account.type, // 'sr25519' | 'ed25519' | 'ecdsa'
genesisHash: account.genesisHash, // Optional chain genesis
})
})Subscribe to Account Changes
const unsubscribe = provider.web3AccountsSubscribe((accounts) => {
console.log('Accounts changed:', accounts)
})
// Later: unsubscribe()Signing
Sign Transaction Payload
Sign extrinsic payloads:
import { web3FromAddress } from '@polkadot/extension-dapp'
// Get injector for specific account
const injector = await web3FromAddress(accountAddress)
// Sign payload
const payload = {
address: accountAddress,
blockHash: '0x...',
blockNumber: '0x...',
era: '0x...',
genesisHash: '0x...',
method: '0x...',
nonce: '0x...',
specVersion: '0x...',
tip: '0x...',
transactionVersion: '0x...',
signedExtensions: [...],
version: 4,
}
const result = await provider.web3SignPayload(payload)
console.log({
id: result.id,
signature: result.signature, // Hex signature
})Sign Raw Message
const payload = {
address: accountAddress,
data: '0x48656c6c6f', // Hex-encoded message
type: 'bytes',
}
const result = await provider.web3SignRaw(payload)
console.log({
id: result.id,
signature: result.signature,
})Using with Polkadot.js API
Setup
npm install @polkadot/api @polkadot/extension-dappConnect and Sign Transaction
import { ApiPromise, WsProvider } from '@polkadot/api'
import { web3Enable, web3FromAddress, web3Accounts } from '@polkadot/extension-dapp'
// Enable extensions
await web3Enable('My dApp')
// Get accounts
const accounts = await web3Accounts()
const account = accounts[0]
// Connect to chain
const wsProvider = new WsProvider('wss://rpc.polkadot.io')
const api = await ApiPromise.create({ provider: wsProvider })
// Get injector
const injector = await web3FromAddress(account.address)
// Create and sign transaction
const tx = api.tx.balances.transfer(
recipientAddress,
1000000000000 // 1 DOT (10^12 planck)
)
// Sign and send
const hash = await tx.signAndSend(
account.address,
{ signer: injector.signer }
)
console.log('Transaction hash:', hash.toHex())Listen for Transaction Events
await tx.signAndSend(
account.address,
{ signer: injector.signer },
({ status, events }) => {
if (status.isInBlock) {
console.log('In block:', status.asInBlock.toHex())
}
if (status.isFinalized) {
console.log('Finalized:', status.asFinalized.toHex())
events.forEach(({ event }) => {
if (api.events.system.ExtrinsicSuccess.is(event)) {
console.log('Transaction succeeded')
}
if (api.events.system.ExtrinsicFailed.is(event)) {
console.log('Transaction failed')
}
})
}
}
)RPC Methods
Send RPC Request
const response = await provider.web3RpcSend({
method: 'chain_getHeader',
params: [],
})
console.log('Latest header:', response.result)Subscribe to RPC Events
const subscriptionId = await provider.web3RpcSubscribe(
{
method: 'chain_subscribeNewHeads',
params: [],
},
(response) => {
console.log('New block:', response.result)
}
)
// Unsubscribe later
await provider.web3RpcUnSubscribe()List Available Providers
const providers = await provider.web3RpcListProviders()
console.log('Available providers:', providers)API Reference
Methods
| Method | Description |
|---|---|
web3Enable(dappName) | Enable extension for dApp |
web3Accounts(anyType?) | Get all accounts |
web3AccountsSubscribe(callback) | Subscribe to account changes |
web3SignPayload(payload) | Sign transaction payload |
web3SignRaw(payload) | Sign raw message |
web3RpcSend(request) | Send RPC request |
web3RpcSubscribe(request, callback) | Subscribe to RPC events |
web3RpcUnSubscribe() | Unsubscribe from all |
web3RpcListProviders() | List RPC providers |
web3RpcStartProvider(key) | Start specific provider |
Types
interface InjectedAccount {
address: string // Substrate address
name?: string // Account name
type?: 'sr25519' | 'ed25519' | 'ecdsa'
genesisHash?: string // Optional chain restriction
}
interface SignerPayloadJSON {
address: string
blockHash: string
blockNumber: string
era: string
genesisHash: string
method: string
nonce: string
specVersion: string
tip: string
transactionVersion: string
signedExtensions: string[]
version: number
}
interface SignerPayloadRaw {
address: string
data: string // Hex-encoded data
type: 'bytes' | 'payload'
}
interface SignerResult {
id: number
signature: string // Hex signature
}Supported Chains
| Chain | Description |
|---|---|
| Polkadot | Main relay chain |
| Kusama | Canary network |
| Acala | DeFi hub |
| Moonbeam | EVM-compatible |
| Astar | Smart contract platform |
| Any Substrate | Custom chains |
Error Handling
try {
const result = await provider.web3SignPayload(payload)
} catch (error) {
if (error.message === 'Cancelled') {
console.log('User cancelled signing')
} else {
console.error('Signing failed:', error)
}
}Using with React
import { useState, useEffect } from 'react'
import { web3Enable, web3Accounts } from '@polkadot/extension-dapp'
function usePolkadotWallet() {
const [accounts, setAccounts] = useState([])
const [isConnected, setIsConnected] = useState(false)
const connect = async () => {
const extensions = await web3Enable('My dApp')
if (extensions.length > 0) {
const allAccounts = await web3Accounts()
setAccounts(allAccounts)
setIsConnected(true)
}
}
return { accounts, isConnected, connect }
}Last updated on