In https://stackoverflow.com/a/18658613/779159 is an example of how to calculate the md5 of a file using the built-in crypto library and streams.
var fs = re
If you are using node version >= v10.0.0 then you can use stream.pipeline and util.promisify.
const fs = require('fs');
const crypto = require('crypto');
const util = require('util');
const stream = require('stream');
const pipeline = util.promisify(stream.pipeline);
const hash = crypto.createHash('sha1');
hash.setEncoding('hex');
async function run() {
await pipeline(
fs.createReadStream('/some/file/name.txt'),
hash
);
console.log('Pipeline succeeded');
}
run().catch(console.error);