=head1 Setting up the web interface

As of RT 3.9, RT's web interface speaks PSGI
(L<http://plackperl.org>) which lets you use RT with any PSGI-supported web
server (which includes Apache, nginx, lighttpd, etc).

=head2 Standalone

The standalone RT web server is backed by a pure-Perl server engine
(L<HTTP::Server::PSGI>). This standalone server is appropriate for development
and testing, but is not appropriate for production use.

You should not run this server against port 80 (which is the default port)
because that requires root-level privileges and may conflict with any existing
listeners. So choose a high port (for example 8080) and start the standalone
server with:

    /opt/rt4/sbin/rt-server --port 8080

You can also run C<rt-server> with any other PSGI server, for example,
to use L<Starman>, a high performance preforking server:

    /opt/rt4/sbin/rt-server --server Starman --port 8080

=head2 Apache

B<WARNING>: Both C<mod_speling> and C<mod_cache> are known to break RT.
C<mod_speling> will cause RT's CSS and JS to not be loaded, making RT
appear unstyled. C<mod_cache> will cache cookies, making users be
spontaneously logged in as other users in the system.

See also L<authentication/Apache configuration>, in case you intend to
use Apache to provide authentication.

=head3 prefork MPM

Apache can run with several different
L<Multi-Processing Modules (MPMs)|https://httpd.apache.org/docs/2.4/mpm.html>.
RT is designed to run only with the L<prefork MPM|https://httpd.apache.org/docs/2.4/mod/prefork.html>.
RT will run with the event MPM, but it will run very poorly
and you are likely to see issues like intermittent errors when loading
pages, slowness, and possible excessive memory usage.

In the past, Apache defaulted to the prefork MPM, but the packaged Apache
on many newer Linux systems defaults to event, so it is important to
make sure Apache is configured to use prefork on your RT server.

=head3 mod_fastcgi

    # Tell FastCGI to put its temporary files somewhere sane; this may
    # be necessary if your distribution doesn't already set it
    #FastCgiIpcDir /tmp

    FastCgiServer /opt/rt4/sbin/rt-server.fcgi -processes 5 -idle-timeout 300

    <VirtualHost rt.example.com>
        ### Optional apache logs for RT
        # Ensure that your log rotation scripts know about these files
        # ErrorLog /opt/rt4/var/log/apache2.error
        # TransferLog /opt/rt4/var/log/apache2.access
        # LogLevel debug

        AddDefaultCharset UTF-8

        ScriptAlias / /opt/rt4/sbin/rt-server.fcgi/

        DocumentRoot "/opt/rt4/share/html"
        <Location />
            <IfVersion >= 2.4> # For Apache 2.4
                Require all granted
            </IfVersion>
            <IfVersion < 2.4>  # For Apache 2.2
                Order allow,deny
                Allow from all
            </IfVersion>

            Options +ExecCGI
            AddHandler fastcgi-script fcgi
        </Location>
    </VirtualHost>

=head3 mod_fcgid

B<WARNING>: Before mod_fcgid 2.3.6, the maximum request size was 1GB.
Starting in 2.3.6, this is now 128Kb.  This is unlikely to be large
enough for any RT install that handles attachments.  You can read more
about FcgidMaxRequestLen at
L<http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidmaxrequestlen>

Most distributions will have a mod_fcgid.conf or similar file with
mod_fcgid configurations and you should add:

    FcgidMaxRequestLen 1073741824

to return to the old default.

    <VirtualHost rt.example.com>
        ### Optional apache logs for RT
        # Ensure that your log rotation scripts know about these files
        # ErrorLog /opt/rt4/var/log/apache2.error
        # TransferLog /opt/rt4/var/log/apache2.access
        # LogLevel debug

        AddDefaultCharset UTF-8

        ScriptAlias / /opt/rt4/sbin/rt-server.fcgi/

        DocumentRoot "/opt/rt4/share/html"
        <Location />
            <IfVersion >= 2.4> # For Apache 2.4
                Require all granted
            </IfVersion>
            <IfVersion < 2.4>  # For Apache 2.2
                Order allow,deny
                Allow from all
            </IfVersion>

            Options +ExecCGI
            AddHandler fcgid-script fcgi
        </Location>
    </VirtualHost>

=head3 mod_perl 2.xx

B<WARNING: mod_perl 1.99_xx is not supported.>

B<WARNING>: Due to thread-safety limitations, all timestamps will be
presented in the webserver's default time zone when using the C<worker>
and C<event> MPMs; the C<$Timezone> setting and the user's timezone
preference are ignored.  We suggest the C<prefork> MPM or FastCGI
deployment if your privileged users are in a different timezone than the
one the server is configured for.

B<NOTE>: RT 3.8 and below suggested use of C<SetHandler perl-script>;
this is incorrect for RT 4, and (starting in RT 4.0.11) RT will refuse
to start, to prevent difficulties sending mail from RT.  Change to
C<SetHandler modperl>, as the example below uses.

    <VirtualHost rt.example.com>
        ### Optional apache logs for RT
        # ErrorLog /opt/rt4/var/log/apache2.error
        # TransferLog /opt/rt4/var/log/apache2.access
        # LogLevel debug

        AddDefaultCharset UTF-8

        DocumentRoot "/opt/rt4/share/html"
        <Location />
            <IfVersion >= 2.4> # For Apache 2.4
                Require all granted
            </IfVersion>
            <IfVersion < 2.4>  # For Apache 2.2
                Order allow,deny
                Allow from all
            </IfVersion>

            SetHandler modperl
            PerlResponseHandler Plack::Handler::Apache2
            PerlSetVar psgi_app /opt/rt4/sbin/rt-server
        </Location>
        <Perl>
            use Plack::Handler::Apache2;
            Plack::Handler::Apache2->preload("/opt/rt4/sbin/rt-server");
        </Perl>
    </VirtualHost>

=head3 mod_perl 1.xx

B<WARNING: mod_perl 1.99_xx is not supported.>

To run RT using mod_perl 1.xx please see L<Plack::Handler::Apache1> for
configuration examples.

=head3 Restricting the REST 1.0 mail-gateway

RT processes email via a REST 1.0 endpoint. If you accept email on the same
server as your running RT, you can restrict this endpoint to localhost only
with a configuration like the following:

    # Accept requests only from localhost
    <Location /REST/1.0/NoAuth/mail-gateway>
        Require local
    </Location>

If you run C<bin/rt-mailgate> on a separate server, you can update
the above to allow additional IP addresses.

    <Location /REST/1.0/NoAuth/mail-gateway>
        Require ip 127.0.0.1 ::1 192.0.2.0  # Add your actual IPs
    </Location>

See the L<Apache documentation|https://httpd.apache.org/docs/2.4/mod/mod_authz_host.html>
for additional configuration options.

After adding this configuration, test receiving email and confirm
your C<bin/rt-mailgate> utility and C</etc/aliases> configurations
can successfully submit email to RT.

=head2 nginx

C<nginx> requires that you start RT's fastcgi process externally, for
example using C<spawn-fcgi>:

    spawn-fcgi -u www-data -g www-data -a 127.0.0.1 -p 9000 \
        -- /opt/rt4/sbin/rt-server.fcgi

With the nginx configuration:

    server {
        listen 80;
        server_name rt.example.com;
        access_log  /var/log/nginx/access.log;

        location / {
            fastcgi_param  QUERY_STRING       $query_string;
            fastcgi_param  REQUEST_METHOD     $request_method;
            fastcgi_param  CONTENT_TYPE       $content_type;
            fastcgi_param  CONTENT_LENGTH     $content_length;

            fastcgi_param  SCRIPT_NAME        "";
            fastcgi_param  PATH_INFO          $uri;
            fastcgi_param  REQUEST_URI        $request_uri;
            fastcgi_param  DOCUMENT_URI       $document_uri;
            fastcgi_param  DOCUMENT_ROOT      $document_root;
            fastcgi_param  SERVER_PROTOCOL    $server_protocol;

            fastcgi_param  GATEWAY_INTERFACE  CGI/1.1;
            fastcgi_param  SERVER_SOFTWARE    nginx/$nginx_version;

            fastcgi_param  REMOTE_ADDR        $remote_addr;
            fastcgi_param  REMOTE_PORT        $remote_port;
            fastcgi_param  SERVER_ADDR        $server_addr;
            fastcgi_param  SERVER_PORT        $server_port;
            fastcgi_param  SERVER_NAME        $server_name;
            fastcgi_pass 127.0.0.1:9000;
        }
    }


=head2 lighttpd

    server.modules += ( "mod_fastcgi" )
    $HTTP["host"] =~ "^rt.example.com" {
        fastcgi.server = (
            "/" => (
                "rt" => (
                    "socket"      => "/opt/rt4/var/socket",
                    "bin-path"    => "/opt/rt4/sbin/rt-server.fcgi",
                    "check-local" => "disable",
                    "fix-root-scriptname" => "enable",
                )
            )
        )
    }


=head1 Running RT at /rt rather than /

First you need to tell RT where it's located by setting C<$WebPath> in your
F<RT_SiteConfig.pm>:

    # Important: don't include a trailing slash here.  Read `perldoc
    # etc/RT_Config.pm` for more information.
    Set($WebPath, "/rt");

Then you need to update your Apache configuration to match.  Prefix any RT
related C<ScriptAlias> and C<Location> directives with C</rt>.  You
should also make sure C<DocumentRoot> is B<not> set to
C</opt/rt4/share/html/>, otherwise RT's source will be served from C</>.

For example: if you're using the sample FastCGI config above, you might change
the relevant directives to:

    ScriptAlias /rt /opt/rt4/sbin/rt-server.fcgi/

    # Set DocumentRoot as appropriate for the other content you want to serve
    DocumentRoot /var/www

    <Location /rt>
        ...
    </Location>

If you're using the sample mod_perl configuration, you only need to change the
C<Location> directive.

If you're not using Apache, please see L<Plack::Handler::FCGI> or the web
server's own documentation for configuration examples.
