ReadableStreamBuffer stalls if not used right away

[peller]

I instantiated a ReadableStreamBuffer, attached a 'data' event, and called an asynchronous call which took much longer than the frequency of the running timeout. In the initial run of sendData, amount was zero so sendMore was false and the timer did not continue to run. Only after that did my data come in, and I called put() but the contents were never seen by the observer.

My workaround was to call _read() to wake up the stream.

[timdp]

Confirmed. Easy to reproduce as well:

const {ReadableStreamBuffer} = require('stream-buffers')

const readable = new ReadableStreamBuffer()

readable.on('data', (data) => {
  console.log('data:', data.toString())
})

readable.on('end', () => {
  console.log('end')
})

setTimeout(() => {
  console.log('putting')
  readable.put('abcdef')
  readable.stop()
}, 100)

[rcoenen]

Confirmed - my first NodeJS project ever - I ran into this

in /node_modules/lib/streambuffers/readable_streambuffer.js

this seems to be the culprit: _read probably was underscored indicating it's private and shouldn't be overloaded. The function gets called right away regardless the TimeOut spficied for the StreamBuffer. It finds an empty buffer, returns false, and kille the timer - result: StreamBuffer is now dead.

 this._read = function() {
	  console.log('_read just called');
    if (!sendData.timeout) {
      sendData.timeout = setTimeout(sendData, frequency);
    }
  };

de

[mvachhar]

The override of _read here is fine, as documented here https://nodejs.org/api/stream.html#stream_implementing_a_readable_stream

The issue is as follows:

1. ReadableStreamBuffer is instantiated
2. The stream is unpaused (via pipe, read, data event, etc.)
3. _read is called and sets the sendData timeout event
4. The timeout expires but no data has been put yet
5. Now, call ReadableStreamBuffer.put(...)
6. The code in put buffers the data but does not kick the sendData event
7. Stream hangs

I'd love to get input on a fix before I make a pull request.

[samcday]

3.0.2 has been released with the fix from @mvachhar (thanks!)

[genrym]

I think this issue can be marked as resolved :)

[mvachhar]

Agreed.

…

On Fri, Aug 31, 2018, 2:12 AM Genry Manashirov ***@***.***> wrote: I think this issue can be marked as resolved :) — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#30 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABUiTTUvogFUNmAvDiCqVNLveYYSdZUHks5uWO_xgaJpZM4LvdPN> .