Hi,
I'm using httpd-2.4.62 on fedora40 and I would like to dynamically add a
Canonical Tag to the HTTP Header. I set this in my .htaccess in the
document root.
SetEnvIf Request_URI "(.+)\.pdf$" PDF_CANONICAL_URL=$1\.pdf
Header add Link "<https://%{HTTP_HOST}e%{REDIRECT_PDF_CANONICAL_URL}e>;
rel=\"canonical\"" env=REDIRECT_PDF_CANONICAL_URL
However, the %{HTTP_HOST} variable doesn't seem to be set.
Using "curl -I" displays this:
Link:
<https://(null)/images/joomgallery/details/gallery_2/img-1512_20210924_1725768871.jpg>;
rel="canonical"
I followed the example here:
https://stackoverflow.com/questions/63768450/howto-add-canonical-tag-to-the-http-headers-for-dynamically-generated-pdf
Can you explain where the REDIRECT_ is defined? According to the info at
the stackoverflow link above, it appears to be a fixed variable that
somehow prevents the header above from being duplicated during the
second pass, but I don't fully understand.
Is this the best way to do it? What if I wanted to move it to my apache
config instead of .htaccess? I tried moving it into the VirtualHost
config and it doesn't work. Maybe it's getting lost in the .htaccess
scanning?
What am I missing?
