nifty-wallet/app/scripts/lib/createStreamSink.js

25 lines
626 B
JavaScript

const WritableStream = require('readable-stream').Writable
const promiseToCallback = require('promise-to-callback')
module.exports = createStreamSink
function createStreamSink (asyncWriteFn, _opts) {
return new AsyncWritableStream(asyncWriteFn, _opts)
}
class AsyncWritableStream extends WritableStream {
constructor (asyncWriteFn, _opts) {
const opts = Object.assign({ objectMode: true }, _opts)
super(opts)
this._asyncWriteFn = asyncWriteFn
}
// write from incomming stream to state
_write (chunk, encoding, callback) {
promiseToCallback(this._asyncWriteFn(chunk, encoding))(callback)
}
}