.htaccess cache static content (unless modified)?

Question

Was wondering is this possible in .htaccess?

I'm currently caching .js, .css and all image files via PHP (and providing the cached only if the file has not been modified by checking the filemtime()).

However someone suggested it's possible via .htaccess and much faster, so was hoping maybe someone can shed some light...I've looked around and found various snippets but none which cover what I'm after.

Answer 1

If you've got mod_expires installed on your apache server you can put something like this in your .htaccess file. This example is PHP orientated (actually grabbed from the Drupal 7 .htaccess file) but should serve as a good starting point.

FileETag MTime Size
<IfModule mod_expires.c>
  # Enable expirations.
  ExpiresActive On

  # Cache all files for 2 weeks after access (A).
  ExpiresDefault A1209600

  <FilesMatch \.php$>
    # Do not allow PHP scripts to be cached unless they explicitly send cache
    # headers themselves. Otherwise all scripts would have to overwrite the
    # headers set by mod_expires if they want another caching behavior.
    ExpiresActive Off
  </FilesMatch>
</IfModule>