Subsequent tasks fail sometimes

[thasmo]

Hello!

I'm experiencing some errors when using gulp-clean:

[gulp] Plumber found unhandled error: Error: EPERM, open 'S:\Project\gulpjs.dummy\public\static\image\cat.gif'
[gulp] Plumber found unhandled error: Error: EEXIST, mkdir 'S:\Project\gulpjs.dummy\public\static\image'
[gulp] Plumber found unhandled error: Error: EEXIST, mkdir 'S:\Project\gulpjs.dummy\public\static\image'
[gulp] Plumber found unhandled error: Error: EEXIST, mkdir 'S:\Project\gulpjs.dummy\public\static\image'
[gulp] Plumber found unhandled error: Error: EEXIST, mkdir 'S:\Project\gulpjs.dummy\public\static\image'

I'm not sure why this happens. My gulpfile can be found here: https://github.com/thasmo/gulpjs.dummy/blob/master/gulpfile.js

I'm trying to deleted a directory before running other tasks, but somehow the subsequent tasks do not create the desired directories/files after running gulp-clean. It seems like gulp-clean somehow interferes with the other tasks.

Any idea what that could be?

[thasmo]

I was able to get rid of the error messages, but still - the subsequent tasks do not create files in the directory, which should have been cleaned before. It seems like the cleaning happens after the new files got created.

[thasmo]

If I configure the task to only delete the files inside the directories, all works well. But if I configure to delete the parent directory, new files won't get created correctly.

[peter-vilja]

Hi,

I cloned your repository and it seems like there is an issue with if plugin.

Does it work if you change:

gulp.task('clean', function() {
    return gulp.src('public/static/', {read: false})
        .pipe(plugins.if(plugins.util.env.production, plugins.clean({force: true})));
});

to:

gulp.task('clean', function() {
    return gulp.src('public/static/', {read: false})
        .pipe(plugins.clean({force: true}));
});

and run it with gulp build

Of course this is not a great solution, but it helps to track down the problem.

[thasmo]

@peter-vilja thanks for your fast reply. You're right - seems to be related to the gulp-if plugin. Do you think it's related to https://github.com/robrich/gulp-if/pull/12?

[peter-vilja]

@thasmo No problem. Kind of. I am not sure, maybe the issue might be that gulp-if registers a child listener even when the file passed to stream gulp.src('public/static/'...) doesn't exist.

[peter-vilja]

Or maybe it's not issue with gulp-if, because this seems to cause the same problem.

gulp.task('clean', function() {
    var stream = gulp.src('public/static/', {read: false})
    if (gulp.env.production) {
        stream.pipe(plugins.clean({force: true}));
    }
    return stream;
});

[thasmo]

Weird. As a workaround this is what I do for now: https://github.com/thasmo/gulpjs.dummy/blob/master/gulpfile.js#L56

And it seems to work.

[peter-vilja]

@thasmo Now it seems like the issue is with gulp-load-plugins because this seems to work:

var gulp    = require('gulp'),
    plugins = require('gulp-load-plugins')(),
    server  = require('tiny-lr')();
    clean = require('gulp-clean');

gulp.task('clean', function() {
    var stream = gulp.src('public/static/', {read: false})
    if (plugins.util.env.production) {
        stream.pipe(clean({force: true}));
    }
    return stream;
});

[peter-vilja]

@thasmo I think it's because the gulp-load-plugins emit's 'end' before gulp-clean. Now the dependency system thinks that task is done, but only the gulp-load-plugins is done and the clean finishes later asynchronously.

[thasmo]

@peter-vilja, this again fails sometimes:

var gulp    = require('gulp'),
    plugins = require('gulp-load-plugins')(),
    clean   = require('gulp-clean'),
    server  = require('tiny-lr')();

gulp.task('build', ['clean'], function() {
    return gulp.start('styles', 'scripts', 'images');
});

gulp.task('clean', function() {
    return gulp.src('public/static/', {read: false})
        .pipe(plugins.if(plugins.util.env.production, clean({force: true})));
});

If there're already files in the directory public/static/, it gets removed, but stays empty (no files are generated). If I again execute gulp build --production the directory gets populated correctly.

[peter-vilja]

@thasmo Same thing here the if plugin 'emit's end before clean plugin and the clean is run asynchronously later. Use this one:

gulp.task('clean', function() {
    var stream = gulp.src('public/static/', {read: false})
    if (plugins.util.env.production) {
        stream.pipe(clean({force: true}));
    }
    return stream;
});

[thasmo]

So, are those bugs in if and load-plugins?

[peter-vilja]

@thasmo No. Just the dependency system believes that the task 'clean' is done because 'end' was emitted inside the task. But this 'end' wasn't gulp-clean's 'end' emit it was other plugins ('end') finishing first before gulp-clean. After this the dependency system started to run tasks 'scripts', 'styles' and 'images' and the actual process of clean finishes some where after running the other tasks.

[thasmo]

@peter-vilja, I see. Which would be weird for the if plugin at least, because it makes it useless, no?

[peter-vilja]

@thasmo Well only inside the task which is as a dependency to other task and last pipe is using it I think. For example here it would not be useless:

// Clean
gulp.task('stuff', function() {
    return gulp.src('public/static/*.js', {read: false})
                   .pipe(plugins.concat('app.js'))
               .pipe(gulp.dest('dist'));
});

// Build
gulp.task('build', ['stuff'], function() {
    gulp.run('styles', 'scripts', 'images');
});

I think this should work because now the last pipe .pipe(gulp.dest('dist')); Will emit correctly that the stream ended.

Or maybe this could be fixed in gulp-if by emitting 'end' only after the child process emit's end. I am not 100% sure that this is the issue, but it seems to be.

[thasmo]

@peter-vilja Thanks for your help and feedback. I've opened an issue on the gulp-if issue tracker requesting review on this - which would be helpful I think.

[markgoodyear]

I get a similar issue as above, although without using gulp-if. Perhaps not quite the same issue as above, but get the same outcome.

gulp.task('clean', function() {
    return gulp.src(['.src/assets/'], {read: false})
        .pipe(clean({force: true}));
});

gulp.task('default', ['clean', 'styles', 'scripts', 'imagemin', 'svgmin'])

As the dependancy array all run at the same time, clean doesn't have time to finish before moving on. I could do this:

gulp.task('default', ['clean'], function() {
    gulp.run(['clean', 'styles', 'scripts', 'imagemin', 'svgmin'])
});

However gulp.run() is depreciated so this won't be able to work in future versions. I'm not sure a way to ensure the clean task is fully complete / block all other tasks before finishing?

Cheers

[peter-vilja]

@markgoodyear You could do this.

var gulp = require('gulp');
var clean = require('gulp-clean');
var concat = require('gulp-concat');

gulp.task('styles', ['clean-styles'], function () {...});

gulp.task('scripts', ['clean-scripts'], function () {...});

gulp.task('clean-styles', function () {
  return gulp.src('.src/assets/styles', {read: false})
          .pipe(clean({force: true}));
});

gulp.task('clean-scripts', function () {
  return gulp.src('.src/assets/scripts', {read: false})
          .pipe(clean({force: true}));
});

gulp.task('default', ['styles', 'scripts']);

But this creates quite a lot boilerplate.

Other option is to use gulp.start

gulp.task('clean', function () {
  return gulp.src('.src/assets/', {read: false})
          .pipe(clean({force: true}));
});

gulp.task('default', ['clean'], function () {
  gulp.start('styles', 'scripts');
});

For more information: https://github.com/gulpjs/gulp/issues/193#issuecomment-33296003 https://github.com/robrich/orchestrator

I'll provide an example which shows how to use clean task as a dependency to the README.md

[markgoodyear]

@peter-vilja Yeah that's what I had thought about, though I didn't want to clean the files each time the task is run. I tried to avoid the gulp.start too, as it seems discouraged to use, but it does seem the better (and cleanest, excuse the pun!) method.

[nmccready]

OMG, gulp.start has solved my madness, thank you. They better not deprecate this. I also agree that chaining so many dependencies seems like super overkill. Especially when some tasks do not really need cleaning in front of it!