stream-events

Get an event when you're being sent data or asked for it.

About

This is just a simple thing that tells you when _read and _write have been called, saving you the trouble of writing this yourself. You receive two events reading and writing-- no magic is performed.

This works well with duplexify or lazy streams, so you can wait until you know you're being used as a stream to do something asynchronous, such as fetching an API token.

Use

1$ npm install --save stream-events

1var stream = require('stream')
2var streamEvents = require('stream-events')
3var util = require('util')
4
5function MyStream() {
6  stream.Duplex.call(this)
7  streamEvents.call(this)
8}
9util.inherits(MyStream, stream.Duplex)
10
11MyStream.prototype._read = function(chunk) {
12  console.log('_read called as usual')
13  this.push(new Buffer(chunk))
14  this.push(null)
15}
16
17MyStream.prototype._write = function() {
18  console.log('_write called as usual')
19}
20
21var stream = new MyStream
22
23stream.on('reading', function() {
24  console.log('stream is being asked for data')
25})
26
27stream.on('writing', function() {
28  console.log('stream is being sent data')
29})
30
31stream.pipe(stream)

Using with Duplexify

1var duplexify = require('duplexify')
2var streamEvents = require('stream-events')
3var fs = require('fs')
4
5var dup = streamEvents(duplexify())
6
7dup.on('writing', function() {
8  // do something async
9  dup.setWritable(/*writable stream*/)
10})
11
12fs.createReadStream('file').pipe(dup)