Swift Blockchain Interaction - Polygon Developer Docs

All wallet operations require an active wallet session. Complete auth first, then use oms.wallet.

guard let walletAddress = oms.wallet.walletAddress else {
    throw NSError(domain: "App", code: 1, userInfo: [NSLocalizedDescriptionKey: "No active wallet"])
}

Supported Networks

Use the SDK network registry when passing network to wallet and indexer calls.

let amoy = oms.findNetworkById(chainId: 80002) ?? .polygonAmoy
let polygon = oms.findNetworkByName(name: "polygon")

if let polygon {
    print(amoy.displayName, polygon.id)
}

for network in oms.supportedNetworks {
    print(network.id, network.displayName, network.nativeTokenSymbol)
}

Parameters findNetworkById(chainId:) takes a numeric chain ID. findNetworkByName(name:) takes a registry name such as polygon, amoy, or base-sepolia. Returns oms.supportedNetworks returns every Network supported by the SDK build. Lookup helpers return a Network?.

Send A Transaction

sendTransaction sends native tokens. Amounts are raw base-unit integer strings. Use parseUnits to convert a display value without floating-point precision loss.

let value = try parseUnits(value: "0.01", decimals: 18)

let tx = try await oms.wallet.sendTransaction(
    network: .polygonAmoy,
    to: "0x1111111111111111111111111111111111111111",
    value: value
)

print("Transaction:", tx.txnHash ?? tx.txnId)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network, such as `.polygon` or `.polygonAmoy`.
`to`	`String`	Recipient address.
`value`	`String`	Raw base-unit native token value.
`selectFeeOption`	`FeeOptionSelector?`	Optional fee option selector.
`mode`	`TransactionMode`	Advanced execution option. Omit it for the default behavior.
`waitForStatus`	`Bool`	Defaults to `true`. Set to `false` to return immediately after execution.
`statusPolling`	`TransactionStatusPollingOptions`	Optional fast poll, slow poll, and timeout configuration.

Returns Returns SendTransactionResponse.

Field	Type	Description
`txnId`	`String`	Wallet transaction ID.
`status`	`TransactionStatus`	Latest transaction status returned by OMS Wallet.
`txnHash`	`String?`	Onchain transaction hash when available.

Send Encoded Calldata

Use the request overload when you already have encoded calldata.

let tx = try await oms.wallet.sendTransaction(
    network: .polygonAmoy,
    request: SendTransactionRequest(
        to: "0x2222222222222222222222222222222222222222",
        value: "0",
        data: "0xa9059cbb000000000000000000000000..."
    )
)

print("Contract transaction:", tx.txnHash ?? tx.txnId)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`request`	`SendTransactionRequest`	Request with `to`, raw `value`, and optional encoded calldata `data`.
`selectFeeOption`	`FeeOptionSelector?`	Optional fee option selector.
`waitForStatus`	`Bool`	Defaults to `true`. Set to `false` to return immediately after execution.
`statusPolling`	`TransactionStatusPollingOptions`	Optional fast poll, slow poll, and timeout configuration.

Returns Returns SendTransactionResponse.

Convert Token Values

Use parseUnits before sending display amounts to the wallet API, and formatUnits when showing raw base-unit balances in the UI.

let rawUsdc = try parseUnits(value: "1.23", decimals: 6)
print(rawUsdc) // "1230000"

let displayUsdc = try formatUnits(value: rawUsdc, decimals: 6)
print(displayUsdc) // "1.23"

Parameters

Function	Parameter	Type	Description
`parseUnits`	`value`	`String`	Display amount to convert.
`parseUnits`	`decimals`	`Int`	Token decimals. Defaults to `18`.
`formatUnits`	`value`	`String`	Raw base-unit integer string to format.
`formatUnits`	`decimals`	`Int`	Token decimals. Defaults to `18`.

Returns Both functions return String. They throw UnitConversionError for invalid decimals or invalid numeric strings. parseUnits rounds fractional precision beyond decimals to the nearest base unit.

Call A Contract With Method And Args

Use callContract for state-changing contract methods. The SDK prepares the contract call, executes it, and polls for transaction status.

let amount = try parseUnits(value: "1", decimals: 6)

let tx = try await oms.wallet.callContract(
    network: .polygonAmoy,
    contract: "0x2222222222222222222222222222222222222222",
    method: "transfer(address,uint256)",
    args: [
        AbiArg(type: "address", value: .string("0x1111111111111111111111111111111111111111")),
        AbiArg(type: "uint256", value: .string(amount))
    ]
)

print("Contract call:", tx.txnHash ?? tx.txnId)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`contract`	`String`	Contract address to call.
`method`	`String`	ABI method signature, such as `transfer(address,uint256)`.
`args`	`[AbiArg]?`	Method arguments as ABI args.
`selectFeeOption`	`FeeOptionSelector?`	Optional fee option selector.
`mode`	`TransactionMode`	Advanced execution option. Omit it for the default behavior.
`waitForStatus`	`Bool`	Defaults to `true`. Set to `false` to return immediately after execution.
`statusPolling`	`TransactionStatusPollingOptions`	Optional fast poll, slow poll, and timeout configuration.

Returns Returns SendTransactionResponse.

Select A Fee Option

When OMS Wallet returns fee options, the SDK selects a fee option before execution. If no selector is provided, the SDK uses the first required fee option. On testnets, all transactions are sponsored and do not require picking a fee option. Use FeeOptionSelector.firstAvailable when you want the SDK to choose the first fee option whose availableRaw balance covers the quoted fee value. This is the standard selector for apps that do not need a custom fee-token picker.

let tx = try await oms.wallet.sendTransaction(
    network: .polygon,
    to: "0x1111111111111111111111111111111111111111",
    value: "0",
    selectFeeOption: .firstAvailable
)

You can also provide a custom selector.

let tx = try await oms.wallet.sendTransaction(
    network: .polygon,
    to: "0x1111111111111111111111111111111111111111",
    value: "0",
    selectFeeOption: .custom { options in
        options.first?.selection
    }
)

Parameters FeeOptionSelector receives [FeeOptionWithBalance]. Each item includes feeOption, selection, and optional balance, available, availableRaw, and decimals fields. Returns Return FeeOptionSelection? from custom selectors.

Polling And Status

Transaction helpers execute and poll for transaction status. Fetch status directly when you have a Wallet transaction ID.

let status = try await oms.wallet.getTransactionStatus(txnId: "txn-id")

print("Status:", status.status)
print("Transaction hash:", status.txnHash ?? "pending")

Parameters

Parameter	Type	Description
`txnId`	`String`	Wallet transaction ID returned by `sendTransaction` or `callContract`.

Returns Returns TransactionStatusResponse.

Field	Type	Description
`status`	`TransactionStatus`	Latest Wallet transaction status.
`txnHash`	`String?`	Onchain transaction hash when available.

Transaction writes can throw OmsSdkError with transaction recovery details. If sendTransaction or callContract throws .transactionExecutionUnconfirmed, preserve error.txnId and do not resend the same write automatically. The SDK prepared the transaction, but could not confirm whether execution was submitted. If it throws .transactionStatusLookupFailed, the transaction was submitted, but post-submit status polling failed. Retry getTransactionStatus(txnId:) with the returned txnId.

do {
    let tx = try await oms.wallet.sendTransaction(
        network: .polygonAmoy,
        to: "0x1111111111111111111111111111111111111111",
        value: "0"
    )
    print("Transaction:", tx.txnHash ?? tx.txnId)
} catch let error as OmsSdkError {
    switch error.code {
    case .transactionExecutionUnconfirmed:
        print("Execution unconfirmed:", error.txnId ?? "unknown")
    case .transactionStatusLookupFailed:
        print("Retry status lookup:", error.txnId ?? "unknown")
    default:
        throw error
    }
}

Sign A Message

signMessage returns a hex-encoded signature for the active wallet.

let signature = try await oms.wallet.signMessage(
    network: .polygonAmoy,
    message: "Hello from OMS"
)

print("Signature:", signature)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`message`	`String`	Plaintext message to sign.

Returns Returns String, the hex-encoded signature.

Verify A Message Signature

isValidMessageSignature verifies a message signature against the wallet address you provide.

let isValid = try await oms.wallet.isValidMessageSignature(
    network: .polygonAmoy,
    walletAddress: walletAddress,
    message: "Hello from OMS",
    signature: signature
)

print("Signature valid:", isValid)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`walletAddress`	`String`	Wallet address to verify the signature against.
`message`	`String`	Original plaintext message.
`signature`	`String`	Hex-encoded signature to verify.

Returns Returns Bool.

Sign Typed Data

Use signTypedData for EIP-712 typed data. Build the payload with WebRPCJSONValue values.

let typedData: WebRPCJSONValue = .object([
    "domain": .object([
        "name": .string("Example App"),
        "version": .string("1"),
        "chainId": .integer(80002)
    ]),
    "types": .object([
        "Message": .array([
            .object([
                "name": .string("contents"),
                "type": .string("string")
            ])
        ])
    ]),
    "primaryType": .string("Message"),
    "message": .object([
        "contents": .string("Hello from OMS")
    ])
])

let typedSignature = try await oms.wallet.signTypedData(
    network: .polygonAmoy,
    typedData: typedData
)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`typedData`	`WebRPCJSONValue`	EIP-712 typed-data payload.

Returns Returns String, the hex-encoded signature.

Verify Typed Data

Verify an EIP-712 typed-data signature.

let typedDataValid = try await oms.wallet.isValidTypedDataSignature(
    network: .polygonAmoy,
    walletAddress: walletAddress,
    typedData: typedData,
    signature: typedSignature
)

Parameters

Parameter	Type	Description
`network`	`Network`	Supported SDK network.
`walletAddress`	`String`	Wallet address to verify the signature against.
`typedData`	`WebRPCJSONValue`	Original EIP-712 typed-data payload.
`signature`	`String`	Hex-encoded signature to verify.

Returns Returns Bool.

​Supported Networks

​Send A Transaction

​Send Encoded Calldata

​Convert Token Values

​Call A Contract With Method And Args

​Select A Fee Option

​Polling And Status

​Sign A Message

​Verify A Message Signature

​Sign Typed Data

​Verify Typed Data

Supported Networks

Send A Transaction

Send Encoded Calldata

Convert Token Values

Call A Contract With Method And Args

Select A Fee Option

Polling And Status

Sign A Message

Verify A Message Signature

Sign Typed Data

Verify Typed Data