htaccess Redirect Based on URL Parameter

I had a project where I needed to redirect a URL based on the presence or absence of a URL parameter.

If the URL did not include a URL parameter of email, I had to redirect to another form. We were using Apache as the server, so I could do this with an .htaccess rule.

Specifically,

# Only proceed with the following rule, if "email=" does NOT appear in the URL query string.
RewriteCond %{QUERY_STRING} !email=
# If we are on the page "my-page-needs-email" (and "email=" is missing)
# perform a 302 redirect to https://example.com/page-to-load-when-no-email
# and stop processing this file (`L`)
RewriteRule ^my-page-needs-email$ https://example.com/page-to-load-when-no-email [R=302,L]

Sal Ferrarello (@salcode)

Sal is a PHP developer with a focus on the WordPress platform. He is a conference speaker with a background including Piano Player, Radio DJ, Magician/Juggler, Beach Photographer, and High School Math Teacher. Sal can be found professionally at WebDevStudios, where he works as a senior backend engineer.