Xnap RPC API Documentation

Xnap provides several RPC methods that websites can use to interact with the Nano network through MetaMask. All methods are accessible through the wallet_invokeSnap MetaMask method and return a JSON object.

Connecting to Xnap

const result: any = await window.ethereum.request({
  method: 'wallet_requestSnaps',
  params: {
    // the snapId
    'npm:@obsidia/xnap': {
      // Version is optional, use it to specify the version range of the snap or leave as empty object
      version: '1.0.0',
    },
  },
});

More information about connecting to a snap can be found in MetaMask's docs.

JSON-RPC Methods

xno_getCurrentAddress

Returns the currently active Nano address and a unique Jazzicon representation.

Parameters: None

Returns:

• address: string | undefined - The current Nano address or undefined if no address is selected.
• icon: string | undefined - unique Jazzicon for the address as an SVG element, or undefined if no address is selected.

Example:

const response = await window.ethereum.request({
  method: 'wallet_invokeSnap',
  params: {
    snapId: 'npm:@obsidia/xnap',
    request: {
      method: 'xno_getCurrentAddress',
    },
  },
});

// console.log(response.address); -> "nano_1xyz..."

xno_makeTransaction

Initiates a send transaction. This will prompt the user for confirmation before sending.

Parameters:

• to: string - The recipient's Nano address or a Nano internet identifier.
• value: string - The amount to send (in nano), use decimal point for fractions.

Returns:

• hash: string | undefined - The transaction hash if successful, undefined otherwise

Example:

const response = await window.ethereum.request({
  method: 'wallet_invokeSnap',
  params: {
    snapId: 'npm:@obsidia/xnap',
    request: {
      method: 'xno_makeTransaction',
      params: {
        to: 'nano_1xyz...', // or @[email protected]
        value: '1.5',
      },
    },
  },
});

xno_signMessage

Requests signing a message using the currently active Nano account.

Parameters:

• message: string - The message to sign

Returns:

• signature: string | undefined - The signature if successful, undefined otherwise

Example:

const response = await window.ethereum.request({
  method: 'wallet_invokeSnap',
  params: {
    snapId: 'npm:@obsidia/xnap',
    request: {
      method: 'xno_signMessage',
      params: {
        message: 'Hello, Nano!', // or JSON.stringify({msg: "some message to sign"})
      },
    },
  },
});

Error Handling

All methods may throw errors if:

• The method name is not supported
• The parameters are invalid
• The user rejects the request
• There are network issues
• The Snap is not properly initialized

Errors will be returned in the standard MetaMask error format with appropriate error codes and messages. Full list of error codes can be found here.

Example error handling:

window.ethereum
  .request({
    method: 'wallet_invokeSnap',
    params: {
      snapId: 'npm:@obsidia/xnap',
      request: {
        method: 'xno_makeTransaction',
        params: {
          to: 'invalid_nano_address',
          value: '1.5',
        },
      },
    },
  })
  .then((res: any) => {})
  .catch((error: { code: number, message: string }) => {
    console.error(error.message); // "Method parameters are invalid"
  });