Get Chrome Extension ID in NodeJS

index.ts

import { readFileSync } from 'fs';
import { parse } from 'protobufjs';

if (!process.argv[2]) throw new Error('no arg');

const file = readFileSync(process.argv[2]);
if (!file) throw new Error('no file');

const root = parse(`
	package chromeextensionid;
	syntax = "proto3";

	message CrxFileHeader {
		repeated AsymmetricKeyProof sha256_with_rsa = 2;
		repeated AsymmetricKeyProof sha256_with_ecdsa = 3;
		optional SignedData signed_header_data = 10000;
	}

	message AsymmetricKeyProof {
		optional bytes public_key = 1;
		optional bytes signature = 2;
	}

	message SignedData {
		optional bytes crx_id = 1;
	}
`).root;

const CrxFileHeader = root.lookupType('chromeextensionid.CrxFileHeader');
const headerObj = CrxFileHeader.decode(file.slice(12, 12 + file.readInt32LE(8))) as any;
const crxId = headerObj.signedHeaderData.crxId as Buffer;
const chars = '0123456789abcdefghijklmnop'.split('');
const id = crxId.toString('hex')
	.split('')
	.map(c => chars[chars.findIndex(d => c === d) + 10])
	.join('');
console.log(id);