duplexer2

Like duplexer but using Streams3

1var stream = require("stream");
2
3var duplexer2 = require("duplexer2");
4
5var writable = new stream.Writable({objectMode: true}),
6    readable = new stream.Readable({objectMode: true});
7
8writable._write = function _write(input, encoding, done) {
9  if (readable.push(input)) {
10    return done();
11  } else {
12    readable.once("drain", done);
13  }
14};
15
16readable._read = function _read(n) {
17  // no-op
18};
19
20// simulate the readable thing closing after a bit
21writable.once("finish", function() {
22  setTimeout(function() {
23    readable.push(null);
24  }, 500);
25});
26
27var duplex = duplexer2(writable, readable);
28
29duplex.on("data", function(e) {
30  console.log("got data", JSON.stringify(e));
31});
32
33duplex.on("finish", function() {
34  console.log("got finish event");
35});
36
37duplex.on("end", function() {
38  console.log("got end event");
39});
40
41duplex.write("oh, hi there", function() {
42  console.log("finished writing");
43});
44
45duplex.end(function() {
46  console.log("finished ending");
47});

got data "oh, hi there"
finished writing
got finish event
finished ending
got end event

Overview

This is a reimplementation of duplexer using the Streams3 API which is standard in Node as of v4. Everything largely works the same.

Installation

Available via npm:

$ npm i duplexer2

API

duplexer2

Creates a new DuplexWrapper object, which is the actual class that implements most of the fun stuff. All that fun stuff is hidden. DON'T LOOK.

1duplexer2([options], writable, readable)

1const duplex = duplexer2(new stream.Writable(), new stream.Readable());

Arguments

• options - an object specifying the regular stream.Duplex options, as well as the properties described below.
• writable - a writable stream
• readable - a readable stream

Options

• bubbleErrors - a boolean value that specifies whether to bubble errors from the underlying readable/writable streams. Default is true.

License

3-clause BSD. A copy is included with the source.

Contact

• GitHub (deoxxa)
• Twitter (@deoxxa)
• Email (deoxxa@fknsrs.biz)