Signing

const api = await window.cardano.onekey.enable()
 
const addresses = await api.getUsedAddresses()
const address = addresses[0]
 
// Message to sign
const payload = Buffer.from('Hello Cardano!').toString('hex')
 
const signature = await api.signData(address, payload)
 
console.log({
  signature: signature.signature, // COSE_Sign1 signature
  key: signature.key,             // COSE_Key public key
})

import { COSESign1, COSEKey } from '@emurgo/cardano-message-signing-browser'
 
const coseSign1 = COSESign1.from_bytes(
  Buffer.from(signature.signature, 'hex')
)
const coseKey = COSEKey.from_bytes(
  Buffer.from(signature.key, 'hex')
)
 
// Get the signed payload
const signedPayload = coseSign1.payload()
 
// Verify signature
const publicKey = coseKey.header(0) // Get Ed25519 key
// Verification logic...

try {
  const api = await window.cardano.onekey.enable()
} catch (error) {
  if (error.code === -1) {
    console.log('User rejected connection')
  } else if (error.code === -2) {
    console.log('Account not found')
  } else {
    console.error('Error:', error.message)
  }
}