Ruby On Rails¶

LiteSpeed Web Server supports Ruby on Rails. This article covers setup for LSWS Native mode. For a shared hosting control panel environment with CloudLinux, please refer to this article to enable CloudLinux Ruby and Python selector.

Why Ruby LSAPI?¶

There are five options Rails application setup with LiteSpeed Web Server:

• Ruby LiteSpeed API (Ruby LSAPI)
• LiteSpeed RubyRunner (Run CGI in persistent interpreter like mod_perl to perl)
• FastCGI
• Mongrel
• CGI

In order to maximize the performance of a Rails application, LiteSpeed Technologies developed our own Ruby interface module using our LiteSpeed API protocol, also known as LSAPI. LSAPI is a highly optimized IPC protocol between LiteSpeed web server and a standalone process which yields the best possible performance.

LiteSpeed RubyRunner is an add-on to Ruby LiteSpeed API which allows running plain Ruby CGI in a persistent interpreter without the cost of starting a new ruby process for each CGI script. However, RubyRunner is not as fast as a plain LSAPI script because Ruby interpreter has to do extra work to shield the run-time environment for each CGI script execution. RubyRunner is for running plain ruby CGI scripts unchanged. For Rails applications, Ruby LSAPI is preferred.

For running Rails application, Ruby LSAPI should give you the best performance as well as the least configuration complexity. We will focus on LSAPI for the rest of this guide.

Requirements¶

Before you can set up Ruby on Rails with LiteSpeed Web Server you should have finished the following steps:

1. Latest version of LiteSpeed Web Server
2. Latest Ruby LSAPI
3. A working Ruby application installation

Install Ruby LiteSpeed API extension¶

You can install the Ruby LSAPI extension using RubyGem, like so:

gem install ruby-lsapi

Or, you can download, unpack, and install from source code, like so:

Download Ruby LSAPI from here.

Unpack:

tar zxvf ruby-lsapi.tar.gz
cd ruby-lsapi

Install Ruby LSAPi:

ruby setup.rb config
ruby setup.rb setup
ruby setup.rb install

LiteSpeed Server Config¶

Step 1¶

In the WebAdmin Console, navigate to Server > Rails to configure server-level Ruby on Rails settings. Set the following:

• Ruby Path: /usr/local/bin/ruby (path to the Ruby executable)
• Rails Environment: Production
• Max Connections: 10
• Run On Start Up: Yes (spawn at server-start to decrease 1^st page response time)

Step 2¶

Next, create a virtual host. In this example, our vhost is called "RubyVhost." If you want to run Rails dispatchers in SuEXEC mode, set CGI Set UID Mode to DocRoot UID. Otherwise, set it to Server UID.

Step 3¶

In RubyVhost's Contexts tab, create a new "Rails" context, and set the following values:

• URI: / (an arbitrary URL like /blog/ can be used as long as your Rails app has been configured to work that way)
• Location: /myrailapp/ (Rails application root directory)
• Rails Environment: Production (overrides server-level Rails environment default value)

Step 4¶

HT Access should be disabled in RubyVhost's General tab, if you don't need it for maximum performance. When using "Rails Context," dispatching rules within /myrailapp/public/.htaccess will be ignored.

• Allow Override: None (either check None or don't check anything at all)

Step 5¶

Optional but recommended: Add rewrite rules. The following rules must be added to the RubyVhost's Rewrite tab, to fully enable caching. Using the standard Rails directive caches_page :action will leave .html files in your public directory, but the rules below are necessary for LiteSpeed to pick those up.

RewriteRule ^(.*)/$ $1/index.html [QSA]
RewriteRule ^([^.]+)$ $1.html [QSA]

Also remember to Enable Rewrite. Save your changes and restart the web server.

By default, LSWS uses the 404 handler to forward a request to a backend Rails application. It will serve the static (cached) version of the page if available. If you want to have the page served by the backend application based on a request component other than URL, like a request header, you should use a URL rewrite at the virtual-host level. For example, to serve an AJAX call with a Rails application based on a special header, you can use a rewrite rule like this:

RewriteCond %{HTTP:X-Requested-With} !^$ 
RewriteRule ^/      /dispatch.lsapi   [QSA,L]

Using a Template¶

LiteSpeed Web Server ships with a virtual host template called "EasyRailsWithSuEXEC," which is meant to be used for simple Rails application configuration. The XML template is located in the /lswsinstall/conf/templates/ directory. If you run one Rails application per virtual host and the root URL of your Rails application is /, steps 2 through 4 above can be replaced by adding a member to the template.

For example, you can configure the server-level Rails settings as described in LiteSpeed Server Config Step 1, add a member to the EasyRailsWithSuEXEC template, and continue with Step 5.

To get the same results as above, add a member with the following settings:

• Virtual Host Name: RubyVHost
• Domain: the vhost's domain name
• Aliases: the vhost's aliases if there are any
• Virtual Host Root: /myrailapp/ (the Rails application root directory)

If you need to further customize the virtual host, just click the Instantiate link to generate a dedicated vhost configuration.