Installation

Before installing and activating the LSCache plugin, deactivate all other full-page cache plugins.

Tip

You can still use other types of cache (like object cache), but only one page cache can be used at a time, so you’ll need to disable any other page caches, if you want to use LSCache.

Module Installation

Note

Please see the Overview for the server-level requirements before attempting to install this module.

  1. Download the LSCPS plugin.
  2. Log into your PrestaShop Admin
  3. Set Advanced Parameters > Performance> Debug mode > Disable all overrides to NO. This is required to ensure proper functioning of the ESI hole-punching feature.
  4. Navigate to Modules > Module Catalog, and click on Install a module.
  5. Select the LSCPS zip file.
  6. Enable the module by navigating to LiteSpeed Cache > Settings and setting Enable LiteSpeed Cache to Yes.

Fixing an Error

If you see the following error message, Directory /home/example/example.com/app/logs is not writable, you can fix it like so:

touch /home/example/example.com/app/logs
chown example:example /home/example/example.com/app/logs

Then, upload and install the module again.

.htaccess Update

When you enable or disable LiteSpeed Cache from the plugin, the .htaccess file should be automatically updated. If the update fails, it is usually due to file permissions. You can update it manually if necessary.

At the top of your .htaccess file, located in the document root of your PrestaShop installation, add the following:

# LITESPEED_CACHE_START Do not remove this comment line, LiteSpeedCache plugin will automatically update this block
<IfModule LiteSpeed>
CacheLookup on
</IfModule>
# LITESPEED_CACHE_END

Verify Your Site is Being Cached

Video

See a video demonstration of this topic here.

!Verify Cache Miss

You can verify a page is being served from LSCache through the following steps:

  1. From a non-logged-in browser, navigate to your site, and open the developer tools (usually, right-click > Inspect). Open the Network tab.
  2. Refresh the page.
  3. Click the first resource. This should be an HTML file. For example, if your page is http://example.com/webapp/, your first resource should either be something like example.com/webapp/ or webapp/.
  4. You should see headings similar to these: 
    X-LiteSpeed-Cache: miss
X-LiteSpeed-Cache-Control:public,max-age=1800
X-LiteSpeed-Tag:B1_F,B1_
    These headings mean the page had not yet been cached, but that LiteSpeed has now stored it, and it will be served from cache with the next request.
  5. Reload the page and you should see X-LiteSpeed-Cache: hit in the response header. This means the page is being served by LSCache and is configured correctly.
    !Verify Cache Hit

Alternative Headers

The X-LiteSpeed-Cache header is most common, but you may see X-LSADC-Cache if your site is served by LiteSpeed Web ADC. You may also see X-QC-Cache if your site was served via QUIC.cloud CDN. These alternate headers are also an indication that LSCache is working properly on your site.

Important

If you don't see X-LiteSpeed-Cache: hit or X-LiteSpeed-Cache: miss (or any of the alternative headers), then there is a problem with the LSCache configuration.

Non-Cacheable Pages

Sometimes there are pages which should not be cached. To verify that such pages have indeed been excluded from caching, check the developer tools as described above.

You should see headings similar to these: 

X-LiteSpeed-Cache-Control:no-cache, esi=on
X-LiteSpeed-Tag:B1_F,B1_

X-LiteSpeed-Cache-Control, when set to no-cache, indicates that LiteSpeed Server has served your page dynamically, and that it was intentionally not served from cache.

LSCache Check Tool

There's a simple way to see if a URL is cached by LiteSpeed: the LSCache Check Tool.

Enter the URL you wish to check, and the tool will respond with an easy-to-read Yes or No result, and a display of the URL's response headers, in case you want to examine the results more closely.

!LSCache Check

In addition to LSCache support, the tool can detect cache hits, and can detect when sites are using LiteSpeed Web ADC or QUIC.cloud CDN for caching.

Additionally, a Stale Cache Warning will alert you if browser cache is detected on dynamic pages. This is because browser cache may interfere with the delivery of fresh content

Last update: March 8, 2021