Polkadot

Polkadot integration via OneKey's Polkadot.js-compatible provider

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

• API Reference

• Connecting

• Signing

• Using with Polkadot.js

---

Provider Detection

// OneKey registers as a Polkadot.js extension
const provider = window.$onekey?.polkadot

// Or use the standard web3Enable API

---

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)

// 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:

// 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-dapp

Connect and Sign Transaction

// 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

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 }
}