vinyl-transform

vinyl-transform wraps standard text transform streams so you can write fewer gulp plugins. Fulfills a similar use case to vinyl-map and vinyl-source-stream.

This module lets you take your standard text transform streams from npm, (e.g. envify), and use them in a vinyl pipeline. It'll transparently take care of handling both buffered and streaming vinyl instances for you too.

Usage

createStream(transformFn)

Creates a vinyl transform stream. transformFn(filename) is a function which takes the file's path and returns a text transform stream. If you've used browserify's transform API you'll recognise this pattern: it's effectively the same API used here.

Here's an example of using this to... uppercase a bunch of files:

var transform = require('vinyl-transform')
var map = require('map-stream')
var gulp = require('gulp')

gulp.task('uppercase', function() {
  var uppercaser = transform(function(filename) {
    return map(function(chunk, next) {
      return next(null, chunk.toString().toUpperCase())
    })
  })

  gulp.src('*.txt')
    .pipe(uppercaser)
    .pipe(gulp.dest('dist/'))
})

And convert .gif images into .webm videos:

var createGIFStream = require('gif-video')
var transform = require('vinyl-transform')
var gulp = require('gulp')

gulp.task('gif-to-webm', function() {
  gulp.src('images/*.gif')
    .pipe(transform(createGIFStream))
    .pipe(gulp.dest('dist/videos/'))
})

Or inject scripts into your HTML:

var transform = require('vinyl-transform')
var inject = require('script-injector')
var gulp = require('gulp')

gulp.task('pages', function() {
  var injector = transform(function() {
    return inject(function() {
      console.log('this script wasn\'t here before')
    })
  })

  gulp.src('*.html')
    .pipe(injector)
    .pipe(gulp.dest('dist/'))
})

License

MIT. See LICENSE.md for details.