merge2

Merge multiple streams into one stream in sequence or parallel.

Install

Install with npm

1npm install merge2

Usage

1const gulp = require('gulp')
2const merge2 = require('merge2')
3const concat = require('gulp-concat')
4const minifyHtml = require('gulp-minify-html')
5const ngtemplate = require('gulp-ngtemplate')
6
7gulp.task('app-js', function () {
8  return merge2(
9      gulp.src('static/src/tpl/*.html')
10        .pipe(minifyHtml({empty: true}))
11        .pipe(ngtemplate({
12          module: 'genTemplates',
13          standalone: true
14        })),
15      gulp.src([
16        'static/src/js/app.js',
17        'static/src/js/locale_zh-cn.js',
18        'static/src/js/router.js',
19        'static/src/js/tools.js',
20        'static/src/js/services.js',
21        'static/src/js/filters.js',
22        'static/src/js/directives.js',
23        'static/src/js/controllers.js'
24      ])
25    )
26    .pipe(concat('app.js'))
27    .pipe(gulp.dest('static/dist/js/'))
28})

1const stream = merge2([stream1, stream2], stream3, {end: false})
2//...
3stream.add(stream4, stream5)
4//..
5stream.end()

1// equal to merge2([stream1, stream2], stream3)
2const stream = merge2()
3stream.add([stream1, stream2])
4stream.add(stream3)

1// merge order:
2//   1. merge `stream1`;
3//   2. merge `stream2` and `stream3` in parallel after `stream1` merged;
4//   3. merge 'stream4' after `stream2` and `stream3` merged;
5const stream = merge2(stream1, [stream2, stream3], stream4)
6
7// merge order:
8//   1. merge `stream5` and `stream6` in parallel after `stream4` merged;
9//   2. merge 'stream7' after `stream5` and `stream6` merged;
10stream.add([stream5, stream6], stream7)

1// nest merge
2// equal to merge2(stream1, stream2, stream6, stream3, [stream4, stream5]);
3const streamA = merge2(stream1, stream2)
4const streamB = merge2(stream3, [stream4, stream5])
5const stream = merge2(streamA, streamB)
6streamA.add(stream6)

API

1const merge2 = require('merge2')

merge2()

merge2(options)

merge2(stream1, stream2, ..., streamN)

merge2(stream1, stream2, ..., streamN, options)

merge2(stream1, [stream2, stream3, ...], streamN, options)

return a duplex stream (mergedStream). streams in array will be merged in parallel.

mergedStream.add(stream)

mergedStream.add(stream1, [stream2, stream3, ...], ...)

return the mergedStream.

mergedStream.on('queueDrain', function() {})

It will emit 'queueDrain' when all streams merged. If you set end === false in options, this event give you a notice that should add more streams to merge or end the mergedStream.

stream

option Type: Readable or Duplex or Transform stream.

options

option Type: Object.

• end - Boolean - if end === false then mergedStream will not be auto ended, you should end by yourself. Default: undefined

• pipeError - Boolean - if pipeError === true then mergedStream will emit error event from source streams. Default: undefined

• objectMode - Boolean . Default: true

objectMode and other options(highWaterMark, defaultEncoding ...) is same as Node.js Stream.

License

MIT © Teambition