Symfony2 Assetic with LESS generating empty files on Unix

Yesterday, I tried running the following command using the symfony console to dump my LESS files into a static CSS file, for my site:
php app/console assetic:dump --env=prod --no-debug
On doing so, when I visited my site, no CSS styling had been applied, and when checking the generated file in the /web/bundles/ folder, it was empty.

I'd recently had issues installing and running composer on my fresh installation of Ubuntu, so I assumed it would be a similar issue, namely around the php.ini setting open_basedir.

When viewing the assetic library, specifically in the \Assetic\Filter\LessFilter.php file, I was seeing that Assetic first creates a temporary file in your system temp directory, compiles everything into there, and then outputs it to the file you have specified.

The relevant code doing this:

// LessFilter.php
public function filterLoad(AssetInterface $asset)
    $pb = $this->createProcessBuilder();

    $pb->add($this->nodeBin)->add($input = FilesystemUtils::createTemporaryFile('less'));
    file_put_contents($input, sprintf($format,
        json_encode(array_merge($parserOptions, $this->treeOptions))

    $proc = $pb->getProcess();
    $code = $proc->run();


// FilesystemUtils.php
public static function createTemporaryFile($prefix)
    return tempnam(self::getTemporaryDirectory(), 'assetic_'.$prefix);

public static function getTemporaryDirectory()
    return realpath(sys_get_temp_dir());
My sys_get_temp_dir() is set to /tmp/, however, PHP doesn't have permission to write there because of my open_basedir settings!

The solution

By adding /tmp/ to my open_basedir in php.ini, assetic was able to run successfully and dump the contents of my LESS files into my desired output folder.


Comments have been closed for this post