Utility functions for Addresses

address.ts

import addr, { Address, newAddress } from '@glif/filecoin-address'
import { blake2b } from 'blakejs'
import varint from 'varint'

/**
 * PayloadHashLength defines the hash length taken over addresses using the Actor and SECP256K1 protocols.
 */
export const payloadHashLength = 20

function addressHash (ingest: Uint8Array): Uint8Array {
  return blake2b(ingest, undefined, payloadHashLength)
}

// TODO: PR to @glif/filecoin-address

/**
 * idFromAddress extracts the ID from an ID address.
 */
export function idFromAddress (address: Address): number {
  if (address.protocol() !== addr.Protocol.ID) {
    throw new Error('cannot get ID from non ID address')
  }
  return varint.decode(address.payload())
}

/**
 * newActorAddress returns an address using the Actor protocol.
 */
export function newActorAddress (data: Uint8Array): Address {
  return newAddress(addr.Protocol.ACTOR, addressHash(data))
}

/**
 * newSecp256k1Address returns an address using the SECP256K1 protocol.
 */
export function newSecp256k1Address (pubkey: Uint8Array): Address {
  return newAddress(addr.Protocol.SECP256K1, addressHash(pubkey))
}

/**
 * newBLSAddress returns an address using the BLS protocol.
 */
export function newBLSAddress (pubkey: Uint8Array): Address {
  return newAddress(addr.Protocol.BLS, pubkey)
}