Changing permalinks using mod_rewrite now gives internal server error 500

Question

I just changed my wordpress permalinks from domain.com/%year%/%month%/%post-slug% over to domain.com/%post-slug%

I used the following mod_rewrite rule to redirect all my older URLs to the new ones.

RedirectMatch 301 ^/[0-9]{4}/[0-9]{2}/([a-z0-9\-/]+) http://www.site.com/$1

The problem being this redirected all my date based archives

domain.com/%year%/%month%/%date%

to

domain.com/%date%

as well which gave out a 404 error. I modified the above code to include a character count (a minimum of 3 and a maximum of 300) like this in order to tackle the date problem

RedirectMatch 301 ^/[0-9]{4}/[0-9]{2}/([a-z0-9\-/]{3,300}+) http://www.site.com/$1

But am now getting a 500 Internal Server error.

Any help on this would be appreciated.

Answer 1

I'm not sure what %post-slug% looks like, so I don't know if there is a better way to distinguish between that and a %date%, but I'm inferring that %date% is a 2-digit number, so you can use a negative lookahead assertion to exclude it. Also, you might want to use \d instead of [0-9] (they're interchangeable, but the first one is shorter).

RedirectMatch 301 ^/\d{4}/\d{2}/(?!\d{2}$)([a-z0-9\-/]+) http://www.site.com/$1

That's more reliable than checking the number of characters, unless you're certain that %post-slug% can never be less than three characters. Of course, if %post-slug% can ever be a 2-digit number, the rule I suggested will skip it. But in that case, there's no way for a regex to tell the difference.

Also, I'm assuming, based on what you wrote, that nothing can come after %date%. If there can be another part after that, change the rule to this:

RedirectMatch 301 ^/\d{4}/\d{2}/(?!\d{2}($|/))([a-z0-9\-/]+) http://www.site.com/$2

(Note the $2 at the end instead of $1)

Answer 2

Change the rule to

RedirectMatch 301 ^/[0-9]{4}/[0-9]{2}/([a-z0-9/-]{3,})$ http://www.site.com/$1