add Request::UrlEncoded middleware for "x-www-form-urlencoded" posts

lib/faraday/builder.rb

@@ -2,8 +2,8 @@ module Faraday
   # Possibly going to extend this a bit.
   #
   # Faraday::Connection.new(:url => 'http://sushi.com') do |builder|
-  #   builder.request  :json     # Faraday::Request::JSON
-  #   builder.adapter  :logger   # Faraday::Adapter::Logger
+  #   builder.request  :url_encoded  # Faraday::Request::UrlEncoded
+  #   builder.adapter  :logger       # Faraday::Adapter::Logger
   # end
   class Builder
     attr_accessor :handlers

lib/faraday/request.rb

@@ -13,10 +13,12 @@ module Faraday
     extend AutoloadHelper
 
     autoload_all 'faraday/request',
-      :JSON => 'json'
+      :JSON       => 'json',
+      :UrlEncoded => 'url_encoded'
 
     register_lookup_modules \
-      :json => :JSON
+      :json        => :JSON,
+      :url_encoded => :UrlEncoded
 
     def self.run(connection, request_method)
       req = create

lib/faraday/request/url_encoded.rb

@@ -0,0 +1,14 @@
+module Faraday
+  class Request::UrlEncoded < Faraday::Middleware
+    def call(env)
+      if data = env[:body]
+        env[:request_headers]['Content-Type'] = 'application/x-www-form-urlencoded'
+
+        unless data.respond_to?(:to_str)
+          env[:body] = Faraday::Utils.build_nested_query data
+        end
+      end
+      @app.call env
+    end
+  end
+end

lib/faraday/utils.rb

@@ -22,6 +22,23 @@ module Faraday
     # Make Rack::Utils build_query method public.
     public :build_query
 
+    # Override Rack's version since it doesn't handle non-String values
+    def build_nested_query(value, prefix = nil)
+      case value
+      when Array
+        value.map { |v| build_nested_query(v, "#{prefix}[]") }.join("&")
+      when Hash
+        value.map { |k, v|
+          build_nested_query(v, prefix ? "#{prefix}[#{escape(k)}]" : escape(k))
+        }.join("&")
+      when NilClass
+        prefix
+      else
+        raise ArgumentError, "value must be a Hash" if prefix.nil?
+        "#{prefix}=#{escape(value)}"
+      end
+    end
+
     # Be sure to URI escape '+' symbols to %2B. Otherwise, they get interpreted
     # as spaces.
     def escape(s)

test/request_middleware_test.rb

@@ -30,4 +30,12 @@ class RequestMiddlewareTest < Faraday::TestCase
     assert_equal 'application/json', response.headers['Content-Type']
     assert_equal '{"a":"b"}', response.body
   end
+  
+  def test_url_encoded
+    @conn.builder.swap Faraday::Request::JSON, Faraday::Request::UrlEncoded
+    
+    response = @conn.post('/echo', { :fruit => %w[apples oranges] })
+    assert_equal 'application/x-www-form-urlencoded', response.headers['Content-Type']
+    assert_equal 'fruit[]=apples&fruit[]=oranges', response.body
+  end
 end