=encoding utf-8


=head1 Name


converting_rewrite_rules - Converting rewrite rules


=head1 A redirect to a main site



People who during their shared hosting life used to configure
I<everything> using I<only> ApacheE<rsquo>s .htaccess files,
usually translate the following rules:


    
    RewriteCond  %{HTTP_HOST}  example.org
    RewriteRule  (.*)          http://www.example.org$1



to something like this:


    
    server {
        listen       80;
        server_name  www.example.org  example.org;
        if ($http_host = example.org) {
            rewrite  (.*)  http://www.example.org$1;
        }
        ...
    }







This is a wrong, cumbersome, and ineffective way.
The right way is to define a separate server for C<example.org>:


    
    server {
        listen       80;
        server_name  example.org;
        return       301 http://www.example.org$request_uri;
    }
    
    server {
        listen       80;
        server_name  www.example.org;
        ...
    }




B<NOTE>

On versions prior to 0.9.1, redirects can be made with:

    
        rewrite      ^ http://www.example.org$request_uri?;








=head1



Another example.
Instead of the E<ldquo>upside-downE<rdquo> logic E<ldquo>all that is not
C<example.com> and is not C<www.example.com>E<rdquo>:


    
    RewriteCond  %{HTTP_HOST}  !example.com
    RewriteCond  %{HTTP_HOST}  !www.example.com
    RewriteRule  (.*)          http://www.example.com$1



one should simply define C<example.com>, C<www.example.com>,
and E<ldquo>everything elseE<rdquo>:


    
    server {
        listen       80;
        server_name  example.com www.example.com;
        ...
    }
    
    server {
        listen       80 default_server;
        server_name  _;
        return       301 http://example.com$request_uri;
    }




B<NOTE>

On versions prior to 0.9.1, redirects can be made with:

    
        rewrite      ^ http://example.com$request_uri?;








=head1 Converting Mongrel rules



Typical Mongrel rules:


    
    DocumentRoot /var/www/myapp.com/current/public
    
    RewriteCond %{DOCUMENT_ROOT}/system/maintenance.html -f
    RewriteCond %{SCRIPT_FILENAME} !maintenance.html
    RewriteRule ^.*$ %{DOCUMENT_ROOT}/system/maintenance.html [L]
    
    RewriteCond %{REQUEST_FILENAME} -f
    RewriteRule ^(.*)$ $1 [QSA,L]
    
    RewriteCond %{REQUEST_FILENAME}/index.html -f
    RewriteRule ^(.*)$ $1/index.html [QSA,L]
    
    RewriteCond %{REQUEST_FILENAME}.html -f
    RewriteRule ^(.*)$ $1.html [QSA,L]
    
    RewriteRule ^/(.*)$ balancer://mongrel_cluster%{REQUEST_URI} [P,QSA,L]



should be converted to


    
    location / {
        root       /var/www/myapp.com/current/public;
    
        try_files  /system/maintenance.html
                   $uri  $uri/index.html $uri.html
                   @mongrel;
    }
    
    location @mongrel {
        proxy_pass  http://mongrel;
    }