Brings in basic mounting of Rack apps.

Author: Michael Bleigh

lib/grape/api.rb

@@ -205,6 +205,17 @@ def http_digest(options = {}, &block)
         auth :http_digest, options, &block
       end
 
+      def mount(mounts)
+        mounts = {mounts => '/'} unless mounts.respond_to?(:each_pair)
+
+        mounts.each_pair do |app, path|
+          next unless app.respond_to?(:call)
+          route_set.add_route(app, 
+            path_info: compile_path(path, false)
+          )
+        end
+      end
+
       # Defines a route that will be recognized
       # by the Grape API.
       #
@@ -225,16 +236,12 @@ def route(methods, paths = ['/'], route_options = {}, &block)
 
         endpoint = build_endpoint(&block)
 
-        endpoint_options = {}
-        endpoint_options[:version] = /#{version.join('|')}/ if version
-
         route_options ||= {}
 
         methods.each do |method|
           paths.each do |path|
-
-            compiled_path = compile_path(path)
-            path = Rack::Mount::Strexp.compile(compiled_path, endpoint_options, %w( / . ? ), true)
+            prepared_path = prepare_path(path)
+            path = compile_path(path)
             regex = Rack::Mount::RegexpWithNamedGroups.new(path)
             path_params = regex.named_captures.map { |nc| nc[0] } - [ 'version', 'format' ]
             path_params |= (route_options[:params] || [])
@@ -245,7 +252,7 @@ def route(methods, paths = ['/'], route_options = {}, &block)
               :version => version ? version.join('|') : nil, 
               :namespace => namespace, 
               :method => request_method, 
-              :path => compiled_path,
+              :path => prepared_path,
               :params => path_params}))
 
             route_set.add_route(endpoint, 
@@ -386,7 +393,7 @@ def route_set
         @route_set ||= Rack::Mount::RouteSet.new
       end
 
-      def compile_path(path)
+      def prepare_path(path)
         parts = []
         parts << prefix if prefix
         parts << ':version' if version
@@ -395,6 +402,13 @@ def compile_path(path)
         parts.last << '(.:format)'
         Rack::Mount::Utils.normalize_path(parts.join('/'))
       end
+
+      def compile_path(path, anchor = true)
+        endpoint_options = {}
+        endpoint_options[:version] = /#{version.join('|')}/ if version
+
+        Rack::Mount::Strexp.compile(prepare_path(path), endpoint_options, %w( / . ? ), anchor)
+      end
     end  
 
     reset! 

spec/grape/api_spec.rb

@@ -125,7 +125,7 @@ def app; subject end
       subject.version :v1
 
       subject.namespace :awesome do
-        compile_path('hello').should == '/rad/:version/awesome/hello(.:format)'
+        prepare_path('hello').should == '/rad/:version/awesome/hello(.:format)'
       end
     end
 
@@ -163,9 +163,9 @@ def app; subject end
     it 'should be callable with nil just to push onto the stack' do
       subject.namespace do
         version 'v2'
-        compile_path('hello').should == '/:version/hello(.:format)'
+        prepare_path('hello').should == '/:version/hello(.:format)'
       end
-      subject.send(:compile_path, 'hello').should == '/hello(.:format)'
+      subject.send(:prepare_path, 'hello').should == '/hello(.:format)'
     end
 
     %w(group resource resources segment).each do |als|
@@ -818,4 +818,45 @@ class CommunicationError < RuntimeError; end
       lambda { get '/uncaught' }.should raise_error(CommunicationError)
     end
   end
+
+  describe '.mount.' do
+    let(:mounted_app){ lambda{|env| [200, {}, ["MOUNTED"]]} }
+  
+    context 'with a bare rack app' do
+      before do
+        subject.mount mounted_app => '/mounty'
+      end
+    
+      it 'should make a bare Rack app available at the endpoint' do
+        get '/mounty'
+        last_response.body.should == 'MOUNTED'
+      end
+
+      it 'should anchor the routes, passing all subroutes to it' do
+        get '/mounty/awesome'
+        last_response.body.should == 'MOUNTED'
+      end
+
+      it 'should be able to cascade' do
+        subject.mount lambda{ |env| 
+          headers = {}
+          headers['X-Cascade'] == 'pass' unless env['PATH_INFO'].include?('boo')
+          [200, headers, ["Farfegnugen"]]
+        } => '/'
+
+        get '/boo'
+        last_response.body.should == 'Farfegnugen'
+        get '/mounty'
+        last_response.body.should == 'MOUNTED'
+      end
+    end
+
+    context 'without a hash' do
+      it 'should call through setting the route to "/"' do
+        subject.mount mounted_app
+        get '/'
+        last_response.body.should == 'MOUNTED'
+      end
+    end
+  end
 end