Kotlin SDK sign and verify - Polygon Developer Docs

Signing creates a signature without submitting a transaction. Each wallet family has its own methods: the EVM methods require an active Ethereum wallet, and the Solana and Tron methods require an active wallet of that family. Calling a method with an active wallet of another family throws OMSWalletValidationException before any request. Verification can target any wallet. Pass walletAddress to verify a signature from a specific address, even while signed out. Omit it to verify against the active wallet’s address, which then requires an active session and a wallet of the method’s family.

Sign and verify a message

The message API accepts only String. It does not provide a byte-array or hexadecimal-message overload.

import technology.polygon.omswallet.Network

val message = "Approve login for Example App"
val signature = omsWallet.wallet.signMessage(
    network = Network.AMOY,
    message = message,
)

val valid = omsWallet.wallet.isValidMessageSignature(
    network = Network.AMOY,
    message = message,
    signature = signature,
)

println("Valid: $valid")

Verify with the exact original string and network. Verification returns false for a signature that OMS does not validate; request or session failures throw an OMSWalletException. To verify a signature from a specific wallet, pass its address:

val valid = omsWallet.wallet.isValidMessageSignature(
    network = Network.AMOY,
    message = message,
    signature = signature,
    walletAddress = "0x1111111111111111111111111111111111111111",
)

Sign and verify a Solana message

For a selected Solana wallet, use the Solana-specific methods. Off-chain messages do not take a network because they are not cluster-specific.

val message = "Approve login for example.com"
val signature = omsWallet.wallet.signSolanaMessage(message)

val valid = omsWallet.wallet.isValidSolanaMessageSignature(
    message = message,
    signature = signature,
)

println("Valid: $valid")

Sign and verify EIP-712 typed data

Typed data uses JsonElement. Build the complete EIP-712 payload expected by the application and contract:

import kotlinx.serialization.json.Json
import technology.polygon.omswallet.Network

val typedData = Json.parseToJsonElement(
    """
    {
      "domain": {
        "name": "Example App",
        "version": "1",
        "chainId": 80002
      },
      "types": {
        "EIP712Domain": [
          { "name": "name", "type": "string" },
          { "name": "version", "type": "string" },
          { "name": "chainId", "type": "uint256" }
        ],
        "Message": [
          { "name": "contents", "type": "string" }
        ]
      },
      "primaryType": "Message",
      "message": {
        "contents": "Approve login for Example App"
      }
    }
    """.trimIndent(),
)

val signature = omsWallet.wallet.signTypedData(
    network = Network.AMOY,
    typedData = typedData,
)

val valid = omsWallet.wallet.isValidTypedDataSignature(
    network = Network.AMOY,
    typedData = typedData,
    signature = signature,
)

Use the same typed-data value and network for verification. isValidTypedDataSignature also accepts walletAddress. Verification does not create a transaction.

Sign and verify Tron messages and typed data

For a selected Tron wallet, use the Tron-specific methods. They do not take a network.

val message = "Approve login for Example App"
val signature = omsWallet.wallet.signTronMessage(message)

val valid = omsWallet.wallet.isValidTronMessageSignature(
    message = message,
    signature = signature,
)

signTronTypedData and isValidTronTypedDataSignature sign and verify TIP-712 typed data. Build the complete TIP-712 payload as a JsonElement, as in the EIP-712 example. Address values in the payload may be Base58Check strings that start with T.

val typedSignature = omsWallet.wallet.signTronTypedData(tronTypedData)

val typedValid = omsWallet.wallet.isValidTronTypedDataSignature(
    typedData = tronTypedData,
    signature = typedSignature,
)

Both Tron verification methods accept an optional Base58Check walletAddress.