CRX parser.
npm install crx-parser --save
var parseCRX = require('crx-parser');
fs.readFile('/tmp/mfabfdnimhipcapcioneheloaehhoggk.crx', function (err, buff) {
parseCRX(buff, function (err, data) {
console.log(data.header.publicKey);
...
});
});
For complete example see test/index.spec.js.