@ckb-lumos/helpers

Helper utilities for working with CKB transactions from lumos.

The difference between this and @ckb-lumos/base, is that @ckb-lumos/base contains only core definitions, while this module contains utilities used in a framework sense. One example is: you can pretty much use @ckb-lumos/base as a standalone library, while this library integrates more with config module so it knows whether the framework is running under testnet, or mainnet environment.

Usage

const {
  minimalCellCapacity,
  generateAddress,
  parseAddress,
} = require("@ckb-lumos/helpers");

// Get cell minimal capacity.
const result = minimalCellCapacity({
  cellOutput: {
    capacity: "0x174876e800",
    lock: {
      args: "0x36c329ed630d6ce750712a477543672adab57f4c",
      codeHash:
        "0x9bd7e06f3ecf4be0f2fcd2188b23f1b9fcc88e5d4b65a8637b17723bbda3cce8",
      hashType: "type",
    },
    type: null,
  },
  data: "0x",
  blockHash: null,
  blockNumber: null,
  outPoint: null,
});

// result will be 6100000000n shannons.

// Use `generateAddress` to get address from lock script.
const address = generateAddress({
  codeHash:
    "0x9bd7e06f3ecf4be0f2fcd2188b23f1b9fcc88e5d4b65a8637b17723bbda3cce8",
  hashType: "type",
  args: "0x36c329ed630d6ce750712a477543672adab57f4c",
});

// Then you will get mainnet address "ckb1qyqrdsefa43s6m882pcj53m4gdnj4k440axqdt9rtd", or you can generate testnet address by
const { predefined } = require("@ckb-lumos/config-manager");

const address = generateAddress(
  {
    codeHash:
      "0x9bd7e06f3ecf4be0f2fcd2188b23f1b9fcc88e5d4b65a8637b17723bbda3cce8",
    hashType: "type",
    args: "0x36c329ed630d6ce750712a477543672adab57f4c",
  },
  { config: predefined.AGGRON4 }
);

// Will get testnet address "ckt1qyqrdsefa43s6m882pcj53m4gdnj4k440axqswmu83".

// Use `parseAddress` to get lock script from an address.
const script = parseAddress("ckb1qyqrdsefa43s6m882pcj53m4gdnj4k440axqdt9rtd");

// TransactionSkeleton <=> Object

// Convert TransactionSkeleton to js object
const obj = transactionSkeletonToObject(txSkeleton);
// then your can write to json file
fs.writeFileSync("your file", JSON.stringify(obj));

// Or convert js object to TransactionSkeleton
// If your object is from json file, make sure `cellProvider` is working properly.
const txSkeleton = objectToTransactionSkeleton(obj);

ModelHelpers

The ModelHelper provides a set of common methods, such as create, hash, clone, and equals, for CKB-related objects. This helper is designed to work with a ModelLike object for convenience, allowing developers to work with ambiguous objects instead of just the strict object.

export type ModelHelper<Model, ModelLike = Model> = {
  create(modelLike: ModelLike): Model;
  equals(modelLike: ModelLike, modelR: ModelLike): boolean;
  hash(modelLike: ModelLike): Uint8Array;
  clone(model: ModelLike): Model;
};

import { cellHelper } from "@ckb-lumos/helpers";

const cell = cellHelper.create({
  lock: "ckb1qzda0cr08m85hc8jlnfp3zer7xulejywt49kt2rr0vthywaa50xwsqgqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq5m759c",
});

const _61CKB = 61 * 10 ** 8;
asserts(BI.from(cell.cellOutput.capacity).eq(_61CKB)); // 61 CKB