Opcat Wallet API

You can refer to this for the instructions of integrating Opcat Wallet with dApps. This doc covers more specific APIs provided by the Opcat Wallet.

Browser Detection

To verify if the browser is running Opcat Wallet, copy and paste the code snippet below in the developer console of your web browser:

if (typeof window.opcat !== "undefined") {
  console.log("Opcat Wallet is installed!");
}

You can review the full API for the window.opcat object

Additionally, since many wallets have forked Opcat's code, multiple window.opcat objects may conflict with each other. To avoid such conflicts, we have introduced a new opcat_wallet object.

if (typeof window.opcat_wallet !== "undefined") {
  console.log("Opcat Wallet is installed!");
}

Connect to the Opcat Wallet

"Connecting" or "logging in" to Opcat Wallet effectively means "to access the user's OP_CAT Layer account(s)".

You should only initiate a connection request in response to direct user action, such as clicking a button. You should always disable the "connect" button while the connection request is pending. You should never initiate a connection request on page load.

We recommend that you provide a button to allow the user to connect Opcat Wallet to your dapp. Clicking this button should call the following method:

requestAccounts

opcat.requestAccounts()

Connect the current account.

Parameters

none

Returns

Promise returns string[] : Address of current account.

try {
  let accounts = await window.opcat.requestAccounts();
  console.log('connect success', accounts);
} catch (e) {
  console.log('connect failed');
}
> connect success ['tb1qrn7tvhdf6wnh790384ahj56u0xaa0kqgautnnz']

disconnect

opcat.disconnect()

Disconnect the current account.

Parameters

none

Returns

Promise returns void

window.opcat.disconnect();

Access accounts

Once the dApp successfully connects to the wallet, you can use the following method to obtain the wallet's address and public key.

getAccounts

opcat.getAccounts()

Get address of current account

Parameters

none

Returns

Promise - string: address of current account

Example

try {
    let res = await window.opcat.getAccounts();
    console.log(res)
} catch (e) {
    console.log(e);
}

> ["tb1qrn7tvhdf6wnh790384ahj56u0xaa0kqgautnnz"]

Additional Note

Although this API returns an array, it currently returns at most one record, which represents the wallet's currently active address.
When the wallet is not connected, it returns an empty array.

getPublicKey

 opcat.getPublicKey()

Get publicKey of current account.

Parameters

none

Returns

Promise - string: publicKey

Example

try {
    let res = await window.opcat.getPublicKey();
    console.log(res)
} catch (e) {
    console.log(e);
}

> 03cbaedc26f03fd3ba02fc936f338e980c9e2172c5e23128877ed46827e935296f

accountsChanged

opcat.on('accountsChanged', handler: (accounts: Array<string>) => void);
opcat.removeListener('accountsChanged', handler: (accounts: Array<string>) => void);

The accountsChanged will be emitted whenever the user's exposed account address changes.

Manage Assets

The following provides several methods to list the wallet's assets and construct corresponding send transactions.

getBalance

opcat.getBalance()

Get cBTC balance

Parameters

none

Returns

Promise - Object:
- confirmed - number : the confirmed satoshis
- unconfirmed - number : the unconfirmed satoshis
- total - number : the total satoshis

Example

try {
    let res = await window.opcat.getBalance();
    console.log(res)
} catch (e) {
    console.log(e);
}

> {
    "confirmed":0,
    "unconfirmed":100000,
    "total":100000
}

getPaymentUtxos

opcat.getPaymentUtxos(cursor,size)

getPaymentUtxos

Parameters

Returns

Promise - object:
- txid - string: The txid
- vout - integer: The output index
- satoshis - integer: The output value
- scriptPk - string: The output script, hex format
- data - string: The output data, hex format

sendTransfer

opcat.sendTransfer(toAddress, satoshis, options)

Send Transfer

Parameters

toAddress - string: the address to send
satoshis - number: the satoshis to send
options - object: (optional)
- feeRate - number: the network fee rate
- memo - string: (optional) The data content of OP_RETURN, which needs to be in UTF-8 or HEX encoded format.
- memos - string[]: (optional) The data content of OP_RETURN, which needs to be in UTF-8 or HEX encoded format, provided in the form of an array.

Returns

Promise - string: txid

Example

try {
  let txid = await window.opcat.sendTransfer(
    "tb1qrn7tvhdf6wnh790384ahj56u0xaa0kqgautnnz",
    1000
  );
  console.log(txid);
} catch (e) {
  console.log(e);
}

Manage Networks

Opcat Wallet currently supports the following network types, which can be obtained through opcat.getNetwork, and switched through the opcat.switchNetwork method.

name	unit	network
Opcat Layer Mainnet	cBTC	livenet
Opcat Layer Testnet	tcBTC	testnet

getNetwork

opcat.getNetwork()

get network

Parameters

none

Returns

Promise - Object:
- name - string: The network name
- network - string : livenet or testnet

Example

try {
  let res = await window.opcat.getNetwork();
  console.log(res)
} catch (e) {
  console.log(e);
}

>  {name: 'Opcat Layer Mainnet', network: 'livenet'}

switchNetwork

opcat.switchNetwork(network)

switch network

Parameters

network - string: the network. livenet or testnet

Returns

Promise - Object:
- name - string : the name of network
- network - string : livenet or testnet

Example

try {
    let res = await window.opcat.switchnetwork("OPCAT_MAINNET");
    console.log(res)
} catch (e) {
    console.log(e);
}

> {enum: 'OPCAT_MAINNET', name: 'OP_CAT Layer Mainnet', network: 'livenet'}

networkChanged

opcat.on('networkChanged', handler: ({name: string, network: string}) => void);

opcat.removeListener('networkChanged', handler: (name: string, network: string) => void);

The networkChanged will be emitted whenever the user's network changes.

Signing

signPsbt

opcat.signPsbt(psbtHex[, options])

Sign PSBT

This method will traverse all inputs that match the current address to sign.

Parameters

psbtHex - string: the hex string of psbt to sign
options
- autoFinalized - boolean: whether finalize psbt after signing, default is true
- toSignInputs - array:
  - index - number: which input to sign
  - address - string: (at least specify either an address or a publicKey) Which corresponding private key to use for signing
  - publicKey - string: (at least specify either an address or a publicKey) Which corresponding private key to use for signing
  - sighashTypes - number[]: (optionals) sighashTypes

Returns

Promise - string: the hex string of signed psbt

Example

try {
  let res = await window.opcat.signPsbt("70736274ff01007d....", {
    autoFinalized: false,
    toSignInputs: [
      {
        index: 0,
        address: "tb1q8h8....mjxzny",
      },
      {
        index: 1,
        publicKey: "tb1q8h8....mjxzny",
        sighashTypes: [1],
      },
      {
        index: 2,
        publicKey: "02062...8779693f",
      },
    ],
  });
  console.log(res);
} catch (e) {
  console.log(e);
}

opcat.signPsbt("xxxxxxxx", {
  toSignInputs: [{ index: 0, publicKey: "xxxxxx", disableTweakSigner: true }],
  autoFinalized: false,
});

signPsbts

opcat.signPsbts(psbtHexs[, options])

Sign Multiple PSBTs at once

This method will traverse all inputs that match the current address to sign.

Parameters

psbtHexs - string[]: the hex strings of psbt to sign
options - object[]: the options of signing psbt
- autoFinalized - boolean: whether finalize psbt after signing, default is true
- toSignInputs - array:
  - index - number: which input to sign
  - address - string: (at least specify either an address or a publicKey) Which corresponding private key to use for signing
  - publicKey - string: (at least specify either an address or a publicKey) Which corresponding private key to use for signing

Returns

Promise - string[]: the hex strings of signed psbt

Example

try {
  let res = await window.opcat.signPsbts([
    "70736274ff01007d...",
    "70736274ff01007d...",
  ]);
  console.log(res);
} catch (e) {
  console.log(e);
}

Additional Note

Batch signing can improve user experience, but it also introduces security risks. Therefore, we require users to review the transaction details one by one before signing. We do provide a convenient "Sign All" button, but it's currently only available for trusted applications. If you need this feature, please open an issue to apply for access.

signMessage

opcat.signMessage(msg[, type])

sign message

Parameters

msg - string: a string to sign
type - string: (Optional) "ecdsa" | "bip322-simple". default is "ecdsa"

Returns

Promise - string: the signature.

Example

// sign by ecdsa
try {
    let res = await window.opcat.signMessage("abcdefghijk123456789");
    console.log(res)
} catch (e) {
    console.log(e);
}

> G+LrYa7T5dUMDgQduAErw+i6ebK4GqTXYVWIDM+snYk7Yc6LdPitmaqM6j+iJOeID1CsMXOJFpVopvPiHBdulkE=

Opcat Wallet API

Browser Detection​

Connect to the Opcat Wallet​

requestAccounts​

disconnect​

Access accounts​

getAccounts​

getPublicKey​

accountsChanged​

Manage Assets​

getBalance​

getPaymentUtxos​

sendTransfer​

Manage Networks​

getNetwork​

switchNetwork​

networkChanged​

Signing​

signPsbt​

signPsbts​

signMessage​

Browser Detection

Connect to the Opcat Wallet

requestAccounts

disconnect

Access accounts

getAccounts

getPublicKey

accountsChanged

Manage Assets

getBalance

getPaymentUtxos

sendTransfer

Manage Networks

getNetwork

switchNetwork

networkChanged

Signing

signPsbt

signPsbts

signMessage