forked from lix-project/lix-website
100 lines
2 KiB
Markdown
100 lines
2 KiB
Markdown
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# duplexer3
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Like [`duplexer2`](https://github.com/deoxxa/duplexer2) but using Streams3 without readable-stream dependency
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```js
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var stream = require("stream");
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var duplexer3 = require("duplexer3");
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var writable = new stream.Writable({objectMode: true}),
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readable = new stream.Readable({objectMode: true});
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writable._write = function _write(input, encoding, done) {
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if (readable.push(input)) {
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return done();
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} else {
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readable.once("drain", done);
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}
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};
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readable._read = function _read(n) {
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// no-op
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};
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// simulate the readable thing closing after a bit
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writable.once("finish", function() {
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setTimeout(function() {
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readable.push(null);
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}, 500);
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});
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var duplex = duplexer3(writable, readable);
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duplex.on("data", function(e) {
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console.log("got data", JSON.stringify(e));
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});
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duplex.on("finish", function() {
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console.log("got finish event");
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});
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duplex.on("end", function() {
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console.log("got end event");
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});
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duplex.write("oh, hi there", function() {
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console.log("finished writing");
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});
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duplex.end(function() {
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console.log("finished ending");
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});
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```
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```
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got data "oh, hi there"
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finished writing
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got finish event
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finished ending
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got end event
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```
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## Overview
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This is a reimplementation of [duplexer](https://www.npmjs.com/package/duplexer) using the
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Streams3 API which is standard in Node as of v4. Everything largely
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works the same.
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## Install
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```sh
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npm install duplexer3
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```
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## API
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### duplexer3
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Creates a new `DuplexWrapper` object, which is the actual class that implements
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most of the fun stuff. All that fun stuff is hidden. DON'T LOOK.
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```js
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duplexer3([options], writable, readable)
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```
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```js
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const duplex = duplexer3(new stream.Writable(), new stream.Readable());
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```
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Arguments
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* __options__ - an object specifying the regular `stream.Duplex` options, as
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well as the properties described below.
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* __writable__ - a writable stream
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* __readable__ - a readable stream
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Options
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* __bubbleErrors__ - a boolean value that specifies whether to bubble errors
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from the underlying readable/writable streams. Default is `true`.
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