Don't work with If-Modified-Since

It works as expected. Just checked so as to be 100% sure. How do you request the document?

BTW, the 304 response code is returned by the web server and not wordpress.

Please check the description page for examples using curl.

I’m marking this topic as resolved. Please feel free to re-open if it does not work for you.

George

I’m sorry, I did not know what the header should give the server

Hello,

Please use curl like this.

First take a note of the date returned in the Last-modified header.

curl -I -L https://example.org/sample-page/
...
...
Last-Modified: Sun, 12 Oct 2014 04:19:00 GMT
...
...

Then send the If-Modified-Since header by providing a date later than the above (here I check for a time ~5 hours ahead of the Last-Modified time).

curl -I -L -H "If-Modified-Since: Sun, 12 Oct 2014 09:00:00 GMT" https://example.org/sample-page/

The response should contain:

HTTP/1.1 304 Not Modified
...
...
...

Hope this helps.

George

Considering to add my last post to a mini curl tutorial on the description page. If this hasn’t been helpful enough, please let me know.

Or you could be lazy and check it here ~ https://varvy.com/tools/if-modified/