htaccess redirect all subdomains to the same directory - apache

Question

I want to be able to redirect all subdomains to a folder:
RewriteCond %{HTTP_HOST} ^([^/.]+)\.example\.com$
RewriteRule (.+)$ "http://example.com/subdomains/%1" [L,P]
for example, if some visits sub1.example.com it will keep the URL but show example.com/subdomains/sub1 and if the sub1 directory does not exist, it will show example.com/404
Is this possible?
I tried the above code but its showing me:
Forbidden
You don't have permission to access /index.php on this server.
Wordpress says:
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress
and at the top of my htaccess file, is:
RewriteEngine On
DirectoryIndex index.php
RewriteCond %{HTTP_HOST} admin.domain.com$
RewriteRule ^(.*)$ /admin/system/$1 [L]

Answer 1

Your above .htaccess would externally redirect the calls, as you use a full URL as the target.
In your question you say you want to keep the hostname, so I will assume that is the requirement.
0) Enable rewrite engine
RewriteEngine On
1) Rewriting known subdomains to their directory in /subdomains
# Rewrite known subdomains to /subdomains/{subdomain}/
RewriteCond %{HTTP_HOST} ^([^/.]+)\.example\.com$
RewriteCond %{REQUEST_URI} !^/subdomains [NC]
RewriteCond %{REQUEST_URI} !^/404 [NC]
RewriteRule ^(.+)$ /subdomains/%1/ [L]
When we encounter a request with a subdomain,
and we have not rewritten it to /subdomains
and we have not rewritten it to /404
then rewrite it to /subdomains/{subdomain}/
So, if the request was
http://foo.example.com/hello
the URL in the browser would stay the same, but internally be mapped to
/subdomains/foo/
2) Rewriting unknown subdomains to /404
# Rewrite missing unknown subdomains to /404/
RewriteCond %{HTTP_HOST} ^([^/.]+)\.example\.com$
RewriteCond %{REQUEST_URI} ^/subdomains [NC]
RewriteCond %{REQUEST_URI} !^/404 [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule ^(.+)$ /404/ [L]
When we encounter a request with a subdomain,
and we have already rewritten it to /subdomains
and we have not rewritten it to /404
and it is not existing as a file
and it is not existing as a directory
and it is not existing as a symlink
then rewrite it to /404
So, if the request was
http://bar.example.com/hello
the URL in the browser would stay the same, but internally be mapped to
/subdomains/bar/
by the first RewriteRule from 1).
If /subdomains/bar/ does not exist, the second RewriteRule from 2) will kick in and internally map it to
/404/
3) Test-Environment
I actually tested all of this with exemplary code, available here: https://github.com/janpapenbrock/stackoverflow-36497197

Answer 2

I'd say you are experiencing a permission issue. I guess your Apache server runs as apache user. Use chmod to give apache access to this path.