Question

Is it possible to process an entire wordpress page (by page I mean the response to any requested url in the site) html with a regex before it gets sent to the client? Is this best achieved by the server rather than php, and how would it get done in apache?

Answer 1

Start output buffering on the beginning with ob_start(), at the end get the contents with $content = ob_get_contents(); ob_end_clean();. You can then run regex on your content with preg_replace and then just echo $content;

Example

ob_start();

echo "Hello World!";

$content = ob_get_contents();
ob_end_clean();

// Outputs "Hello StackOverflow!"
echo preg_replace("/World/", "StackOverflow", $content);