How to redirect URL with htaccess (RewriteRule) and prevent direct access - apache

Question

using .htaccess I'd like to transparently redirect requests for folder "old" to folder "new", and in the same time prevent direct access to folder "new":
desired result:
http://example.com/old/... -> will display what's in "new" (no URL change in browser!)
http://example.com/new/... -> no access
this is my code in .htaccess (the 1st line is here because several domains share the same root folder):
RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
RewriteRule ^old(.*)$ new$1 [L]
RewriteRule ^new(.*)$ - [F]
Well, what happens is that the 3d line triggers because of the substitution in the 2nd. I was convinced that the flag "L" would prevent this from happening (end of processing), but it seems that's not the case.
Do you have any suggestions what needs to be done (I tried to debug with rewrite log, but without success)?
I did some logging and found the following:
[rid#d0ac98/initial] (3) [per-dir C:/www/example/] add path info postfix: C:/www/example/new -> C:/www/example/new/
[rid#d0ac98/initial] (3) [per-dir C:/www/example/] strip per-dir prefix: C:/www/example/new/ -> new/
[rid#d0ac98/initial] (3) [per-dir C:/www/example/] applying pattern '^new(.*)$' to uri 'new/'
[rid#d0ac98/initial] (4) RewriteCond: input='localhost' pattern='^example\.com$' => not-matched
[rid#d0ac98/initial] (4) RewriteCond: input='localhost' pattern='^localhost$' => matched
[rid#d0ac98/initial] (2) [per-dir C:/www/example/] rewrite new/ -> old/
[rid#d0ac98/initial] (3) [per-dir C:/www/example/] add per-dir prefix: old/ -> C:/www/example/old/
[rid#d0ac98/initial] (2) [per-dir C:/www/example/] strip document_root prefix: C:/www/example/old/ -> /example/old/
[rid#d0ac98/initial] (1) [per-dir C:/www/example/] internal redirect with /example/old/ [INTERNAL REDIRECT]
[rid#d217a8/initial/redir#1] (3) [per-dir C:/www/example/] strip per-dir prefix: C:/www/example/old/ -> old/
[rid#d217a8/initial/redir#1] (3) [per-dir C:/www/example/] applying pattern '^new(.*)$' to uri 'old/'
[rid#d217a8/initial/redir#1] (3) [per-dir C:/www/example/] strip per-dir prefix: C:/www/example/old/ -> old/
[rid#d217a8/initial/redir#1] (3) [per-dir C:/www/example/] applying pattern '^old(.*)$' to uri 'old/'
[rid#d217a8/initial/redir#1] (2) forcing 'C:/www/example/old/' to be forbidden
This seems an internal redirect, which causes the "forbidden" result. Indeed, the documentation mentions it:
It is therefore important, if you are using RewriteRule directives in one of these contexts, that you take explicit steps to avoid rules looping, and not count solely on the [L] flag to terminate execution of a series of rules, as shown below. An alternative flag, [END], can be used to terminate not only the current round of rewrite processing but prevent any subsequent rewrite processing from occurring in per-directory (htaccess) context. This does not apply to new requests resulting from external redirects...
So I suppose that in my example the error was due to the fact that I used "L" flag instead the "END" flag?
I found an alternative solution (3rd line is inserted here):
RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
RewriteRule ^old(.*)$ new$1 [L]
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^new(.*)$ - [F]
The 4th line will be executed only if there's no internal redirect.

Answer 1

You can use:
RewriteEngine On
# if directly requesting /new then block it
RewriteCond %{THE_REQUEST} \s/+new(/\S*)?\s [NC]
RewriteRule ^ - [F]
# forward /old/abc to /new/abc
RewriteCond %{HTTP_HOST} ^(www\.)?example\.com$ [NC]
RewriteRule ^old(/.*)?$ new$1 [L,NC]
We used THE_REQUEST in first rule. THE_REQUEST variable represents original request received by Apache from your browser and it doesn't get overwritten after execution of some rewrite rules. REQUEST_URI on the other hand changes its value after other rewrite rules.
For the same reason your rule RewriteRule ^new(.*)$ - [F] will even block your request from /old/ since first rule changes URI to /new/.