htaccess RewriteRule redirect regex

Question

I am trying to redirect url requests from http://www.xyz.com.au/lid/cid_855_1404172

To

http://www.xyz.com.au/lid/1404172

My regex matches the numbers after the last underscore but the final url is still appending the part I’m trying to omit

RewriteRule ([^_]+)$ /lid/$1

The result is:

http://www.xyz.com.au/lid/cid_855_/lid/1404172

What have I done wrong?

Answer 1

To be able to match and replace parts, you need to match all parts of the URI not a partial match.

You may use this redirect rule:

RewriteRule ^(.+/)?[^/]*_([^_]+)/?$ /$1$2 [L,R=301,NE]

Details of the regex used:

• ^: Start
• (.+/)?: Match 1+ of any char followed by a /in capture group #1
• [^/]*: Match 0 or more of any char that are not / (longest possible match; greedy)
• _: Match a _
• ([^_]+): Match 1+ of any char that are not _ in capture group #2
• /?$: Match optional / and end anchor