The PageSpeed modules are open-source server
modules for Apache and Nginx that optimize your site automatically. They offer
different packages which can be installed on your server. You can download packages
here.
By
default, all HTML files served by your server and all resources (CSS, images, JavaScript)
found in HTML files whose origin matches the HTML file, or whose origin is
authorized via Domain, will be rewritten.
www.example.com/wp-content/themes/eatfit/images/xfoot-logo.png.pagespeed.ic.SWoJqa9Ly9.png
However,
this can be restricted by using wildcards, using the directives:
Apache:
ModPagespeedAllow wildcard_spec
ModPagespeedDisallow wildcard_spec
Nginx:
pagespeed Allow wildcard_spec;
pagespeed Disallow wildcard_spec;
These directives
are evaluated in sequence for each resource, to determine whether the resource
should be consider for rewriting. This is best considered with an example.
Example 1: Excluding JavaScript files that
cannot be rewritten
Some JavaScript files are
sensitive to their own names as they traverse the DOM. Therefore any rewriting
on these files is invalid. We cannot cache-extend them or minifiy them. When
such files are identified, we can exclude from the rewriting process via:
Apache:
ModPagespeedDisallow "*/jquery-ui-1.8.2.custom.min.js"
ModPagespeedDisallow "*/js_tinyMCE.js"
Nginx:
pagespeed Disallow "*/jquery-ui-1.8.2.custom.min.js";
pagespeed Disallow "*/js_tinyMCE.js";
Example2: Specifying explicitly which types of files can be
rewritten
If you don't have access to disable it for your site, you can add ?ModPagespeed=off to the end of your URL in the
browser like this