Gulp copies the file, but it is empty

Question

I have a strange problem. I use gulp to compile the response application and I will copy it index.html into the corresponding web directory. When I start gulp first, everything runs as expected, but when the file changes and the view task is executed, gulp copies the empty version of the file to the web directory. Does anyone know why this might happen? Here is my gulpfile.js:

var gulp = require('gulp');

var browserify = require('browserify');
var babelify = require('babelify');
var source = require('vinyl-source-stream');

var livereload = require('gulp-livereload');

gulp.task('livereload', function() {
    console.log('reloading');
    livereload();
});

gulp.task('copyindextodist', function() {
    gulp.src('app/index.html')
        .pipe(gulp.dest('dist'));
});

gulp.task('compilejs', function() {
    browserify({
        entries: 'app/index.js',
        extensions: ['.js'],
        debug: true
    })
    .transform('babelify', {presets: ['es2015', 'react']})
    .bundle()
    .pipe(source('app.js'))
    .pipe(gulp.dest('dist'));
});

gulp.task('publishapp', function() {
    gulp.src('dist/*.*')
        .pipe(gulp.dest('../public'));
});

gulp.task('copypaste', function() {
    gulp.src('app/index.html')
        .pipe(gulp.dest('../public'));
});

gulp.task('watch', function() {
    livereload.listen();
    gulp.watch('app/index.html', ['copyindextodist']);
    gulp.watch('dist/index.html', ['publishapp']);
    gulp.watch('app/index.js', ['compilejs']);
    gulp.watch('dist/app.js', ['publishapp']);
});

gulp.task('default', ['copyindextodist', 'compilejs', 'publishapp', 'watch']);

Answer 1

I had the same problem until I defined the dependency correctly. You can determine which tasks should be completed before starting the current task:

gulp.task('compress', ['copy'], function() {
    //.... your job
});

, compress copy. , / .

, .

gulp.task('copy', function() {
    // "return" is the important part ;-)
    return gulp.src(['filepath/**/*']) 
        .pipe(gulp.dest('lib/newpath'))
});

, , , :

var gulp = require('gulp');
var merge = require('merge-stream');
gulp.task('copy', function() {
    var allStreams = [
        gulp.src(['node_modules/bootstrap/dist/**/*'])
             .pipe(gulp.dest('lib/bootstrap')),
        gulp.src(['node_modules/jquery/dist/**/*'])
             .pipe(gulp.dest('lib/jquery')),
    ];
    return merge.apply(this, allStreams);
});
gulp.task('nextTask', ['copy'], function() {
    // this task formerly produced empty files, but now
    // has a valid dependency on the copy stream and 
    // thus has all files available when processed.
});