Implements ruby-grape#97: allow overriding Content-Type.

Author: dblock

CHANGELOG.markdown

@@ -11,6 +11,7 @@ Next Release
 * [#159](https://github.com/intridea/grape/pull/159): Added `:requirements` to routes, allowing to use reserved characters in paths - [@gaiottino](https://github.com/gaiottino).
 * [#156](https://github.com/intridea/grape/pull/156): Added support for adding formatters to entities - [@bobbytables](https://github.com/bobbytables).
 * [#183](https://github.com/intridea/grape/pull/183): Added ability to include documentation in entities - [@flah00](https://github.com/flah00).
+* [#97](https://github.com/intridea/grape/issues/97): Allow overriding `Content-Type` - [@dblock](https://github.com/dblock).
 
 0.2.0 (3/28/2012)
 =================

README.markdown

@@ -88,7 +88,7 @@ end
 
 ## Mounting
 
-The above sample creates a Rack application that can be run from a rackup *config.ru* file 
+The above sample creates a Rack application that can be run from a rackup *config.ru* file
 with `rackup`:
 
 ``` ruby
@@ -128,7 +128,7 @@ There are three strategies in which clients can reach your API's endpoints: `:he
 version 'v1', :using => :header
 ```
 
-Using this versioning strategy, clients should pass the desired version in the HTTP Accept head. 
+Using this versioning strategy, clients should pass the desired version in the HTTP Accept head.
 
     curl -H Accept=application/vnd.twitter-v1+json http://localhost:9292/statuses/public_timeline
 
@@ -147,15 +147,15 @@ Using this versioning strategy, clients should pass the desired version in the U
 
     curl -H http://localhost:9292/v1/statuses/public_timeline
 
-Serialization takes place automatically. 
+Serialization takes place automatically.
 
 ### Param
 
 ```ruby
 version 'v1', :using => :param
 ```
 
-Using this versioning strategy, clients should pass the desired version as a request parameter, either in the URL query string or in the request body. 
+Using this versioning strategy, clients should pass the desired version as a request parameter, either in the URL query string or in the request body.
 
     curl -H http://localhost:9292/events?apiver=v1
 
@@ -169,7 +169,7 @@ version 'v1', :using => :param, :parameter => "v"
 
 ## Parameters
 
-Parameters are available through the `params` hash object. This includes `GET` and `POST` parameters, 
+Parameters are available through the `params` hash object. This includes `GET` and `POST` parameters,
 along with any named parameters you specify in your route strings.
 
 ```ruby
@@ -426,9 +426,20 @@ class Twitter::API < Grape::API
 end
 ```
 
+You can override the content-type by setting the `Content-Type` header.
+
+``` ruby
+class API < Grape::API
+  get '/script' do
+    content_type "application/javascript"
+    "var x = 1;"
+  end
+end
+```
+
 ## Writing Tests
 
-You can test a Grape API with RSpec by making HTTP requests and examining the response. 
+You can test a Grape API with RSpec by making HTTP requests and examining the response.
 
 ### Writing Tests with Rack
 
@@ -579,7 +590,7 @@ end
 ### Caveats
 
 Entities with duplicate exposure names and conditions will silently overwrite one another.
-In the following example, when object#check equals "foo", only afield will be exposed. 
+In the following example, when object#check equals "foo", only afield will be exposed.
 However, when object#check equals "bar" both bfield and foo will be exposed.
 
 ```ruby
@@ -611,7 +622,7 @@ end
 
 Grape lets you add a description to an API along with any other optional
 elements that can also be inspected at runtime.
-This can be useful for generating documentation. If the response 
+This can be useful for generating documentation. If the response
 requires documentation, consider using an entity.
 
 ``` ruby

lib/grape/endpoint.rb

@@ -152,7 +152,7 @@ def error!(message, status=403)
     end
 
     # Redirect to a new url.
-    # 
+    #
     # @param url [String] The url to be redirect.
     # @param options [Hash] The options used when redirect.
     #                       :permanent, default true.
@@ -163,7 +163,7 @@ def redirect(url, options = {})
       else
         if env['HTTP_VERSION'] == 'HTTP/1.1' && request.request_method.to_s.upcase != "GET"
           status 303
-        else 
+        else
           status 302
         end
       end
@@ -197,7 +197,12 @@ def header(key = nil, val = nil)
         @header
       end
     end
-
+    
+    # Set response content-type
+    def content_type(val)
+      header('Content-Type', val)
+    end
+    
     # Set or get a cookie
     #
     # @example

lib/grape/middleware/formatter.rb

@@ -73,7 +73,7 @@ def after
         bodymap = bodies.collect do |body|
           formatter.call(body)
         end
-        headers['Content-Type'] = content_types[env['api.format']]
+        headers['Content-Type'] = content_types[env['api.format']] unless headers['Content-Type']
         Rack::Response.new(bodymap, status, headers).to_a
       end
     end

spec/grape/api_spec.rb

@@ -731,12 +731,20 @@ def three
   describe ".content_type" do
     it "sets additional content-type" do
       subject.content_type :xls, "application/vnd.ms-excel"
-      subject.get(:hello) do
+      subject.get :excel do
         "some binary content"
       end
-      get '/hello.xls'
+      get '/excel.xls'
       last_response.content_type.should == "application/vnd.ms-excel"
     end
+    it "allows to override content-type" do
+      subject.get :content do
+        content_type "text/javascript"
+        "var x = 1;"
+      end
+      get '/content'
+      last_response.content_type.should == "text/javascript"
+    end
   end
 
   describe ".default_error_status" do