@dfinity/ledger-icp

ledger-icp-js

A library for interfacing with the ICP ledger on the Internet Computer.

ℹ️ This library is meant to interface with the ICP ledger only. If you are looking to interact with Snses, ckBTC, or other ICRC tokens, use the ledger-icrc-js library.

Table of contents

• Installation
• Usage
• Features
• Resources

Installation

You can use ledger-icp-js by installing it in your project.

npm i @dfinity/ledger-icp

The bundle needs peer dependencies, be sure that following resources are available in your project as well.

npm i @dfinity/agent @dfinity/candid @dfinity/principal @dfinity/utils

Usage

The features are available through the class LedgerCanister. It has to be instantiated with a canister ID.

e.g. fetching a token metadata.

import { createAgent } from "@dfinity/utils";
import { LedgerCanister } from "@dfinity/ledger-icp";

const agent = await createAgent({
  identity,
  host: HOST,
});

const { metadata } = LedgerCanister.create({
  agent,
  canisterId: MY_LEDGER_CANISTER_ID,
});

const data = await metadata();

Features

ledger-icp-js implements following features:

:factory: AccountIdentifier

:link: Source

Static Methods

• fromHex
• fromPrincipal

:gear: fromHex

Method	Type
fromHex	(hex: string) => AccountIdentifier

:link: Source

:gear: fromPrincipal

Method	Type
fromPrincipal	({ principal, subAccount, }: { principal: Principal; subAccount?: SubAccount or undefined; }) => AccountIdentifier

:link: Source

Methods

• toHex
• toUint8Array
• toNumbers
• toAccountIdentifierHash

:gear: toHex

Method	Type
toHex	() => string

:link: Source

:gear: toUint8Array

Method	Type
toUint8Array	() => Uint8Array

:link: Source

:gear: toNumbers

Method	Type
toNumbers	() => number[]

:link: Source

:gear: toAccountIdentifierHash

Method	Type
toAccountIdentifierHash	() => { hash: Uint8Array; }

:link: Source

:factory: SubAccount

:link: Source

Static Methods

• fromBytes
• fromPrincipal
• fromID

:gear: fromBytes

Method	Type
fromBytes	(bytes: Uint8Array) => SubAccount

:link: Source

:gear: fromPrincipal

Method	Type
fromPrincipal	(principal: Principal) => SubAccount

:link: Source

:gear: fromID

Method	Type
fromID	(id: number) => SubAccount

:link: Source

Methods

• toUint8Array

:gear: toUint8Array

Method	Type
toUint8Array	() => Uint8Array

:link: Source

:factory: LedgerCanister

:link: Source

Static Methods

• create

:gear: create

Method	Type
create	(options?: LedgerCanisterOptions) => LedgerCanister

:link: Source

Methods

• accountBalance
• metadata
• transactionFee
• transfer
• icrc1Transfer
• icrc2Approve
• icrc21ConsentMessage

:gear: accountBalance

Returns the balance of the specified account identifier.

If certified is true, the request is fetched as an update call, otherwise it is fetched using a query call.

Method	Type
accountBalance	({ accountIdentifier: accountIdentifierParam, certified, }: AccountBalanceParams) => Promise<bigint>

Parameters:

• params: The parameters to get the balance of an account.
• params.accountIdentifier: The account identifier provided either as hex string or as an AccountIdentifier.
• params.certified: query or update call.

Returns:

The balance of the given account.

:link: Source

:gear: metadata

Fetches the ledger metadata.

Method	Type
metadata	(params: QueryParams) => Promise<[string, Value][]>

Parameters:

• params: - The parameters used to fetch the metadata, notably query or certified call.

Returns:

The metadata of the ICP ledger. A promise that resolves to an array of metadata entries, where each entry is a tuple consisting of a string and a value.

:link: Source

:gear: transactionFee

Returns the transaction fee of the ICP ledger canister.

Method	Type
transactionFee	(params?: QueryParams) => Promise<bigint>

Parameters:

• params: - Optional query parameters for the request, defaulting to { certified: false } for backwards compatibility reason.

Returns:

A promise that resolves to the transaction fee as a bigint.

:link: Source

:gear: transfer

Transfer ICP from the caller to the destination accountIdentifier. Returns the index of the block containing the tx if it was successful.

Method	Type
transfer	(request: TransferRequest) => Promise<bigint>

:link: Source

:gear: icrc1Transfer

Transfer ICP from the caller to the destination Account. Returns the index of the block containing the tx if it was successful.

Method	Type
icrc1Transfer	(request: Icrc1TransferRequest) => Promise<bigint>

:link: Source

:gear: icrc2Approve

This method entitles the spender to transfer token amount on behalf of the caller from account { owner = caller; subaccount = from_subaccount }.

Reference: https://github.com/dfinity/ICRC-1/blob/main/standards/ICRC-2/README.md#icrc2_approve

Method	Type
icrc2Approve	(params: Icrc2ApproveRequest) => Promise<bigint>

Parameters:

• params: - The parameters to approve.

Returns:

The block index of the approved transaction.

:link: Source

:gear: icrc21ConsentMessage

Fetches the consent message for a specified canister call, intended to provide a human-readable message that helps users make informed decisions.

Method	Type
icrc21ConsentMessage	(params: Icrc21ConsentMessageRequest) => Promise<icrc21_consent_info>

Parameters:

• params: - The request parameters containing the method name, arguments, and consent preferences (e.g., language).

Returns:

• A promise that resolves to the consent message response, which includes the consent message in the specified language and other related information.

:link: Source

:factory: IndexCanister

:link: Source

Static Methods

• create

:gear: create

Method	Type
create	({ canisterId: optionsCanisterId, ...options }: CanisterOptions<_SERVICE>) => IndexCanister

:link: Source

Methods

• accountBalance
• getTransactions

:gear: accountBalance

Returns the balance of the specified account identifier.

Method	Type
accountBalance	({ certified, accountIdentifier, }: AccountBalanceParams) => Promise<bigint>

Parameters:

• params: The parameters to get the balance of an account.
• params.accountIdentifier: The account identifier provided either as hex string or as an AccountIdentifier.
• params.certified: query or update call.

Returns:

The balance of the given account.

:link: Source

:gear: getTransactions

Returns the transactions and balance of an ICP account.

Method	Type
getTransactions	({ certified, accountIdentifier, start, maxResults: max_results, }: GetTransactionsParams) => Promise<GetAccountIdentifierTransactionsResponse>

Parameters:

• params: The parameters to get the transactions.
• params.certified: query or update call.
• params.accountIdentifier: The account identifier provided either as hex string or as an AccountIdentifier.
• params.start: If set then the results will start from the next most recent transaction id after start (start won't be included). If not provided, then the results will start from the most recent transaction id.
• params.maxResults: Maximum number of transactions to fetch.

Returns:

The transactions, balance and the transaction id of the oldest transaction the account has.

:link: Source

Resources

• Ledger & Tokenization Working Group Standards
• ICP ledger