Understanding THE_REQUEST variable in RewriteCond

Question

RewriteCond %{THE_REQUEST} ^(.+)\.php([#?][^\ ]*)?\ HTTP/

I understand everything in the line above except for the following segment:

([#?][^\ ]*)?\ HTTP/

I've done some research and found out that the square brackets are used to match any one of the characters within them. However, I have also learned that ? is used to make the preceding token optional and that ^ means "match start."

As such, why do the square brackets in the segment above contain both ? and ^? I thought that the square brackets were simply used as a "character class."

Also, what is the purpose of HTTP/ in the segment specifically? All of my searches have come to no avail.

Answer 1

First understand what is THE_REQUEST.

THE_REQUEST variable represents original request received by Apache from your browser and it doesn't get overwritten after execution of some rewrite rules. Example value of this variable is:

GET /index.php?id=123 HTTP/1.1

Now the part you want more clarification on:

([#?][^\ ]*)?\ HTTP/

Here is what is happening here:

1. It matches ? or # literally since inside [...] almost all special characters are matched literally
2. Followed by a negated character class that matches 0 or more characters of anything except a space
3. ? after ([#?][^\ ]*) makes it an optional match
4. \ HTTP matches a space followed by HTTP

Now let me tell you that matching # is not needed here since a web server never receives a URL after #. That is all handled by client browsers.

It is better to use this RewriteCond:

RewriteCond %{THE_REQUEST} ^(.+)\.php(\?\S*)?\ HTTP/ [NC]