Add apply_filter to CDN rewrite_srcset

[webtrainingwheels]

Our CDN rewrite looks for specific patterns of srcset
If developers are using a custom attribute name, we won't detect it for rewriting. We could make the $pattern filterable to address this.

Related ticket: https://secure.helpscout.net/conversation/1200037694/174367?folderId=377611

Can you guys please add an apply_filter() to the $pattern? That is the best solution as it makes WPRocket a lot more flexible for all situations. As your code currently is assuming data-srcset/data-lazy-srcset, but due to plugin + theme incompatibilities, themes have to have their own custom attributes for things like this.

[GeekPress]

I checked the website and all attributes are using the CDN. I suppose that the user found another way to apply our CDN, isn't it?

If so, a filter isn't required.

[codetipi]

@GeekPress Not quite - I ended up editing the plugin's CDN.php file to manually change the pattern for it to work.

Please can you add a filter so that I don't have to edit core plugin files after each update :)

Thanks in advance!

P.s @webtrainingwheels Thanks for opening this.

[GeekPress]

@codetipi Thanks for the feedback ;)

We will add a filter there.

[engahmeds3ed]

Reproduce the issue ✅
Tested locally with other lazyload attributes and found the need to use a filter here.

Scope a solution ✅

wp-rocket/inc/Engine/CDN/CDN.php

Line 63 in 28e7b00

$pattern = '#\s+(?:data-lazy-|data-)?srcset\s*=\s*["\']\s*(?<sources>[^"\',\s]+\.[^"\',\s]+(?:\s+\d+[wx])?(?:\s*,\s*[^"\',\s]+\.[^"\',\s]+\s+\d+[wx])*)\s*["\']#i';

Here we can apply filter rocket_cdn_srcset_attributes so it will return/change the following part of the regex data-lazy-|data- so if for example our theme is using the attribute data-wow-src we will use this filter to return data-lazy-|data-|data-wow-.
I think this is better than add the full regex to the filter not to break the full main functionality.

Estimate the effort ✅
Effort [XS].