redirect potential API calls to API, fixes #32

Gemfile

@@ -5,6 +5,7 @@ source :rubygems
 gem 'puma'
 gem 'rack-ssl', '~> 1.3'
 gem 'rack-cache'
+gem 'sinatra'
 
 group :development, :test do
   gem 'rake', '~> 0.9.2'
@@ -23,3 +24,8 @@ group :development do
   gem 'guard'
   gem 'rb-fsevent', '~> 0.9.1'
 end
+
+group :test do
+  gem 'rspec', '~> 2.11'
+  gem 'sinatra-contrib'
+end

Gemfile.lock

@@ -50,6 +50,8 @@ GEM
     rack (1.4.1)
     rack-cache (1.2)
       rack (>= 0.4)
+    rack-protection (1.2.0)
+      rack
     rack-ssl (1.3.2)
       rack
     rake (0.9.2.2)
@@ -57,6 +59,10 @@ GEM
     rerun (0.7.1)
       listen
     sass (3.2.1)
+    sinatra (1.3.3)
+      rack (~> 1.3, >= 1.3.6)
+      rack-protection (~> 1.2)
+      tilt (~> 1.3, >= 1.3.3)
     thor (0.16.0)
     tilt (1.3.3)
     uglifier (1.3.0)
@@ -80,5 +86,6 @@ DEPENDENCIES
   rake-pipeline-web-filters!
   rb-fsevent (~> 0.9.1)
   rerun
+  sinatra
   tilt
   uglifier

config.ru

@@ -4,6 +4,11 @@ ENV['RAILS_ENV']  = ENV['RACK_ENV']
 
 $: << 'lib'
 require 'travis/web'
+
+use Travis::Web::ApiRedirect do |config|
+  config.api_endpoint = ENV['API_ENDPOINT'] if ENV['API_ENDPOINT']
+end
+
 run Travis::Web::App.new(
   environment:  ENV['RACK_ENV'] || 'development',
   api_endpoint: ENV['API_ENDPOINT'],

lib/travis/web.rb

@@ -1,5 +1,6 @@
 module Travis
   module Web
-    autoload :App, 'travis/web/app'
+    autoload :ApiRedirect, 'travis/web/api_redirect'
+    autoload :App,         'travis/web/app'
   end
 end

lib/travis/web/api_redirect.rb

@@ -0,0 +1,43 @@
+require 'sinatra'
+
+class Travis::Web::ApiRedirect < Sinatra::Base
+  disable :protection, :static
+  set api_endpoint: 'https://api.travis-ci.org'
+
+  set :api_types, %w[
+    application/vnd.travis-ci.1+json
+    application/vnd.travis-ci.1+xml
+    application/vnd.travis-ci.1+png
+    application/xml
+    application/json
+  ]
+
+  set :frontend_types, %w[
+    text/html application/xhtml+xml
+  ]
+
+  get '/:owner_name/:name.png' do
+    redirect!
+  end
+
+  after do
+    redirect! if catch_all? and api_call?
+  end
+
+  private
+
+    def catch_all?
+      headers['Content-Location'] == '/' and request.path_info != '/'
+    end
+
+    def api_call?
+      return true if request.accept.empty?
+      preferred = request.preferred_type(*settings.frontend_types, *settings.api_types)
+      settings.api_types.include? preferred
+    end
+
+    def redirect!
+      path = File.join(settings.api_endpoint, request.fullpath)
+      redirect(path, 301)
+    end
+end

spec/api_redirect_spec.rb

@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+describe Travis::Web::ApiRedirect do
+  let(:browser_accept) { 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8' }
+
+  it 'does not redirect normal requests' do
+    get('/').should_not be_redirect
+  end
+
+  it 'redirects /:owner/:repo.png' do
+    get('/foo/bar.png').should be_redirect
+  end
+
+  it 'does not redirect catch-all for browsers' do
+    get('/foo/bar', {}, 'HTTP_ACCEPT' => browser_accept).should_not be_redirect
+  end
+
+  it 'does not redirect catch-all with generic Accept header' do
+    get('/foo/bar', {}, 'HTTP_ACCEPT' => '*/*').should_not be_redirect
+  end
+
+  it 'redirects catch-all without Accept header' do
+    get('/foo/bar').should be_redirect
+  end
+
+  it 'redirects catch-all JSON requests' do
+    get('/foo/bar', {}, 'HTTP_ACCEPT' => 'application/json').should be_redirect
+  end
+
+  it 'does not redirect asset requests' do
+    get('/version').should_not be_redirect
+  end
+end

spec/spec_helper.rb

@@ -0,0 +1,13 @@
+ENV['RACK_ENV'] = 'test'
+
+require 'sinatra/contrib'
+require 'travis/web'
+
+ru_file = File.expand_path('../../config.ru', __FILE__)
+web_app = Rack::Builder.parse_file(ru_file).first
+
+RSpec.configure do |config|
+  config.expect_with :rspec, :stdlib
+  config.include Sinatra::TestHelpers
+  config.before(:each) { set_app(web_app) }
+end