Change file names when updating the cache

[Shmasser]

Hi. v.1.6.0.9 Does anyone know, why when you refresh the cache every time the Files is rewritten the JS and CSS with a new name? Even if these files have not been changed.

This leads to inadequate display of pages in the cache of search engines. In the file /classes/Media.php has the following lines:

	public static function clearCache()
	{
		foreach (array(_PS_THEME_DIR_.'cache') as $dir)
			if (file_exists($dir))
				foreach (scandir($dir) as $file)
					if ($file[0] != '.' && $file != 'index.php')
						Tools::deleteFile($dir.DIRECTORY_SEPARATOR.$file, array('index.php'));

		$version = (int)Configuration::get('PS_CCCJS_VERSION');
		Configuration::updateValue('PS_CCCJS_VERSION', ++$version);
		$version = (int)Configuration::get('PS_CCCCSS_VERSION');
		Configuration::updateValue('PS_CCCCSS_VERSION', ++$version);
	}

which change the version number (and change the name of the site).

What is the meaning of these changes and what will happen, if to remove these lines from your code and leave the file names unchanged?

Edited August 29, 2016 by Shmasser (see edit history)

[vekia]

it is for browser caching purpose

if you will have, for example XXXXXXXX.css file name all the time browser will display old contents of this file (because browser will display cached version of file)

new file name = new load of file contents.

[Shmasser]

But why the old CSS and JS files are renamed when you upgrade the cache? To the version number is the last. For example, there was v_355_XXX, v_356_XXX now

Edited August 29, 2016 by Shmasser (see edit history)