Added versioner middleware.

Author: Michael Bleigh

README.rdoc

@@ -3,16 +3,28 @@
 Grape is a REST-like API micro-framework for Ruby. It is built to complement existing web application frameworks such as Rails and Sinatra by providing a simple DSL to easily provide APIs. It has built-in support for common conventions such as multiple formats, subdomain/prefix restriction, and versioning.
 
     class Twitter < Grape::Base
-      # Set this API to work only on a specified subdomain
       subdomain 'api'
+      version '1'
+      formats :xml, :json
+      authorization :oauth, User
 
-      # Use a path prefix.
-      path_prefix 'api'
-      
-      version 'v2'
-      
-      version 'v1' do
+      resource :statuses do
+        group :timelines do
+          formats :rss, :atom
+          
+          get :public_timeline do
+            optional :trim_user, Boolean
+            optional :include_entities, Boolean
+          
+            Tweet.limit(20)
+          end
 
+          get :home_timeline do
+            authorized
+          
+            user.home_timeline
+          end
+        end
       end
     end
 

lib/grape.rb

@@ -2,4 +2,5 @@
 require 'rack/builder'
 
 require 'grape/middleware/base'
-require 'grape/middleware/prefixer'
+require 'grape/middleware/prefixer'
+require 'grape/middleware/versioner'

lib/grape/middleware/base.rb

@@ -5,9 +5,11 @@ class Base
 
       def initialize(app, options = {})
         @app = app
-        @options = options
+        @options = default_options.merge(options)
       end
 
+      def default_options; {} end
+      
       def call(env)
         dup.call!(env)
       end

lib/grape/middleware/versioner.rb

@@ -0,0 +1,23 @@
+require 'grape/middleware/base'
+
+module Grape
+  module Middleware
+    class Versioner < Base
+      def default_options
+        {
+          :pattern => /.*/i
+        }
+      end
+      
+      def before
+        pieces = env['PATH_INFO'].split('/')
+        potential_version = pieces[1]
+        if potential_version =~ options[:pattern]
+          truncated_path = "/#{pieces[2..-1].join('/')}"
+          env['api.version'] = potential_version
+          env['PATH_INFO'] = truncated_path
+        end
+      end
+    end
+  end
+end

spec/grape/middleware/base_spec.rb

@@ -39,7 +39,25 @@
     subject.response.should be_kind_of(Rack::Response)
   end
 
-  it 'should persist options passed at initialization' do
-    Grape::Middleware::Base.new(blank_app, {:abc => true}).options[:abc].should be_true
+  context 'options' do
+    it 'should persist options passed at initialization' do
+      Grape::Middleware::Base.new(blank_app, {:abc => true}).options[:abc].should be_true
+    end
+    
+    context 'defaults' do
+      class ExampleWare < Grape::Middleware::Base
+        def default_options
+          {:monkey => true}
+        end
+      end
+      
+      it 'should persist the default options' do
+        ExampleWare.new(blank_app).options[:monkey].should be_true
+      end
+      
+      it 'should override default options when provided' do
+        ExampleWare.new(blank_app, :monkey => false).options[:monkey].should be_false
+      end
+    end
   end
 end

spec/grape/middleware/versioner_spec.rb

@@ -0,0 +1,29 @@
+require 'spec_helper'
+
+describe Grape::Middleware::Versioner do
+  let(:app) { lambda{|env| [200, env, env['api.version']]} }
+  subject { Grape::Middleware::Versioner.new(app, @options || {}) }
+  
+  it 'should set the API version based on the first path' do
+    subject.call('PATH_INFO' => '/v1/awesome').last.should == 'v1'
+  end
+  
+  it 'should cut the version out of the path' do
+    subject.call('PATH_INFO' => '/v1/awesome')[1]['PATH_INFO'].should == '/awesome'
+  end
+  
+  it 'should provide a nil version if no path is given' do
+    subject.call('PATH_INFO' => '/').last.should be_nil
+  end
+  
+  context 'with a pattern' do
+    before{ @options = {:pattern => /v./i} }
+    it 'should set the version if it matches' do
+      subject.call('PATH_INFO' => '/v1/awesome').last.should == 'v1'
+    end
+    
+    it 'should ignore the version if it fails to match' do
+      subject.call('PATH_INFO' => '/awesome/radical').last.should be_nil
+    end
+  end
+end