gulp-fncallback

Add own callback to streaming

Install

npm install gulp-fncallback

Usage transformFunction

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      console.log(file);
      cb();
    }))
    .pipe(gulp.dest('./public/css'));
});

Usage transformFunction and flushFunction

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      console.log(file);
      cb();
    }, function (callback) {
      callback();
    }))
    .pipe(gulp.dest('./public/css'));
});

Usage transformFunction with error

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      console.log(file);
      cb('error');
    }))
    .pipe(gulp.dest('./public/css'));
});

Usage transformFunction with new file

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      var newFile = ...
      cb(null, newFile);
    }))
    .pipe(gulp.dest('./public/css'));
});

Usage transformFunction with new file and append old file

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      var newFile = ...
      cb(null, newFile, true);
    }))
    .pipe(gulp.dest('./public/css'));
});

Options

once - Run callback once

var less = require('gulp-less');
var callback = require('gulp-fncallback');

gulp.task('less', function () {
  gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(callback(function (file, enc, cb) {
      console.log(file);
      cb();
    }, {
      once: true
    }))
    .pipe(gulp.dest('./public/css'));
});