Rack::Domain

Rack::Domain is a Rack middleware that enables you to intercept a request with a specific domain or subdomain (or regexp that matches a domain, actually) and route it to a specific application.

Add this line to your application's Gemfile:

gem 'rack-domain'

And then execute:

$ bundle

Or install it yourself as:

$ gem install rack-domain

Rack::Domain supports three kinds of filters in order to match a domain.

• A string: it will match only if the string is exactly the same as the domain.
• A regexp: it will match if the domain matches the regexp.
• An array of strings and regexps: it will match if at least one of the elements of the array matches (as described above) the domain.

To decide where to dispatch the request if there's a match, you can use an existing Rack app through the :run option, or you can pass a block in which you can use the classic use|run|map... syntax. This works because the block is directly passed to a new instance of Rack::Builder.

Using a regexp:

# Match the 'lobster' subdomain.
use Rack::Domain, /^lobster\./, run: Rack::Lobster.new

Using a string:

# Match only if the current domain is github.com:
use Rack::Domain, 'github.com', run: MyGitHubClone

Using an array of strings and regexps:

use Rack::Domain, ['lobst.er', /^lobster\./], run: Rack::Lobster.new

Using an on-the-fly app build with a Rack::Builder-style block:

use Rack::Domain, /^api/ do
  use Rack::Logger
  run MyApi
end

Fork, make changes, commit, open Pull Request, be awesome! Read the GitHub guide to forking if you don't know how to.

Also, issues are more than welcome! Open one if you find a bug, you have a suggestion or simply to ask a question.