I found two great tutorial about installing subversion with http access and using the authz mod.
In short do the following:
sudo apt-get install subversion libapache2-svn
sudo a2enmod dav_svn
sudo nano /etc/apache2/mods-enabled/dav_svn.conf
Enter this:
<Location /svn>
DAV svn
SVNPath /srv/svn
AuthType Basic
AuthName "Subversion Repository"
AuthUserFile /etc/apache2/dav_svn.passwd
AuthzSVNAccessFile /etc/apache2/permission.authz
Require valid-user
</Location>
Create a svn repository folder under /srv/svn
sudo mkdir /srv/svn
sudo svnadmin create /home/svn
Change the owner of the file
sudo chown -R www-data:subversion /srv/svn
sudo htpasswd -cm /etc/apache2/dav_svn.passwd SVN-USERNAME1
Enter a password
sudo htpasswd -m /etc/apache2/dav_svn.passwd SVN-USERNAME2
Enter a password
Now create and edit the file to hold the permissions and groups
sudo vim /etc/apache2/permission.authz
Enter groups
[groups] red = USER1, USER2 blue = USER3
Enter the permissions
[/] * = [red-repo] @red = rw @blue = r [blue-repo] @red = r @blue = rw
Restart apache
sudo /etc/init.d/apache2 restart
These are the two mentioned tutorials, with small changes to work on current Debian and respecting the /srv directory mentioned at :
Subversion over Apache 2 on Ubuntu
Access Control for Subversion with Apache2 and Authz
Have fun!