Browser

Do some browser detection with Ruby. Includes ActionController integration.

Installation

gem install browser

Usage

require "rubygems"
require "browser"

browser = Browser.new(:ua => "some string", :accept_language => "en-us")
browser.name            # readable browser name
browser.version         # major version number
browser.full_version
browser.safari?
browser.opera?
browser.chrome?
browser.chrome_os?
browser.mobile?
browser.tablet?
browser.console?
browser.firefox?
browser.ie?
browser.ie6?            # this goes up to 11
browser.edge?           # Newest MS browser
browser.modern?         # Webkit, Firefox 17+, IE 9+ and Opera 12+
browser.platform        # return :mac, :windows, :linux or :other
browser.mac?
browser.windows?
browser.windows_x64?
browser.linux?
browser.blackberry?
browser.bot?
browser.search_engine?
browser.phantom_js?
browser.quicktime?
browser.core_media?
browser.silk?
browser.known?          # has the browser been successfully detected?
browser.meta            # an array with several attributes
browser.to_s            # the meta info joined by space

See the tests and implementation for more examples.

What defines a modern browser?

The current rules that define a modern browser are pretty loose:

• Webkit
• IE9+
• Firefox 17+
• Firefox Tablet 14+
• Opera 12+

You can define your own rules. A rule must be a proc/lambda or any object that implements the method === and accepts the browser object. To redefine all rules, clear the existing rules before adding your own.

# Only Chrome Canary is considered modern.
Browser.modern_rules.clear
Browser.modern_rules << -> b { b.chrome? && b.version >= '37' }

Rails integration

Just add it to the Gemfile.

gem "browser"

This adds a helper method called browser, that inspects your current user agent.

<% if browser.ie6? %>
  <p class="disclaimer">You're running an older IE version. Please update it!</p>
<% end %>

Bots

Browser used to detect empty user agents as bots, but this behaviour has changed. If you want to bring this detection back, you can activate it through the following call:

Browser::Bots.detect_empty_ua!

Middleware

You can use the Browser::Middleware to redirect user agents.

use Browser::Middleware do
  redirect_to "/upgrade" unless browser.modern?
end

If you're using Rails, you can use the route helper methods. Just add something like the following to a initializer file (config/initializers/browser.rb).

Rails.configuration.middleware.use Browser::Middleware do
  redirect_to upgrade_path unless browser.modern?
end

Notice that you can have multiple conditionals.

Rails.configuration.middleware.use Browser::Middleware do
  next if browser.search_engine?
  redirect_to upgrade_path(browser: "oldie") if browser.ie? && !browser.modern?
  redirect_to upgrade_path(browser: "oldfx") if browser.firefox? && !browser.modern?
end

If you need acccess to the Rack::Request object (e.g. to exclude a path), you can do so with request.

Rails.configuration.middleware.use Browser::Middleware do
  redirect_to upgrade_path unless browser.modern? || request.env['PATH_INFO'] == '/exclude_me'
end

Maintainer

• Nando Vieira - http://nandovieira.com.br

Contributors

• https://github.com/fnando/browser/contributors

License

(The MIT License)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.