Hash#to_json takes :only or :except options to specific or omit certain hash keys. Enumerable#to_json passes through its options to each element. Closes #9751.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7736 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/serializers/json_serializer.rb

@@ -1,6 +1,6 @@
 module ActiveRecord #:nodoc:
   module Serialization
-    def to_json(options = {}, &block)
+    def to_json(options = {})
       JsonSerializer.new(self, options).to_s
     end
 

activerecord/test/json_serialization_test.rb

@@ -68,11 +68,12 @@ class DatabaseConnectedJsonEncodingTest < Test::Unit::TestCase
 
   def setup
     @david = authors(:david)
+    @mary = authors(:mary)
   end
 
   def test_includes_uses_association_name
     json = @david.to_json(:include => :posts)
-    
+
     assert_match %r{"posts": \[}, json
 
     assert_match %r{"id": 1}, json
@@ -140,4 +141,37 @@ class DatabaseConnectedJsonEncodingTest < Test::Unit::TestCase
     assert_match %r{"favorite_quote": "Constraints are liberating"}, json
     assert_equal %r{"favorite_quote": }.match(json).size, 1
   end
+
+  def test_should_allow_only_option_for_list_of_authors
+    authors = [@david, @mary]
+
+    assert_equal %([{"name": "David"}, {"name": "Mary"}]), authors.to_json(:only => :name)
+  end
+
+  def test_should_allow_except_option_for_list_of_authors
+    authors = [@david, @mary]
+
+    assert_equal %([{"id": 1}, {"id": 2}]), authors.to_json(:except => [:name, :author_address_id])
+  end
+
+  def test_should_allow_includes_for_list_of_authors
+    authors = [@david, @mary]
+    json = authors.to_json(
+      :only => :name,
+      :include => {
+        :posts => { :only => :id }
+      }
+    )
+
+    assert_equal %([{"name": "David", "posts": [{"id": 1}, {"id": 2}, {"id": 4}, {"id": 5}, {"id": 6}]}, {"name": "Mary", "posts": [{"id": 7}]}]), json
+  end
+
+  def test_should_allow_options_for_hash_of_authors
+    authors_hash = {
+      1 => @david,
+      2 => @mary
+    }
+
+    assert_equal %({1: {"name": "David"}}), authors_hash.to_json(:only => [1, :name])
+  end
 end

activesupport/CHANGELOG

@@ -1,8 +1,10 @@
 *SVN*
 
+* Hash#to_json takes :only or :except options to specific or omit certain hash keys. Enumerable#to_json passes through its options to each element.  #9751 [Chu Yeow]
+
 * BufferedLogger#auto_flushing = N flushes the log every N messages. Buffers with an array instead of string.  [Jeremy Kemper]
 
-* Fixed Date#xmlschema for dates outside the range of what can be created with Time #9744 [gbuesing]
+* Fixed Date#xmlschema for dates outside the range of what can be created with Time #9744 [Geoff Buesing]
 
 
 *2.0.0 [Preview Release]* (September 29th, 2007)

activesupport/lib/active_support/json/encoders/date.rb

@@ -1,5 +1,5 @@
 class Date
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     %("#{strftime("%m/%d/%Y")}")
   end
 end

activesupport/lib/active_support/json/encoders/date_time.rb

@@ -1,5 +1,5 @@
 class DateTime
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     %("#{strftime("%m/%d/%Y %H:%M:%S %Z")}")
   end
 end

activesupport/lib/active_support/json/encoders/enumerable.rb

@@ -1,5 +1,5 @@
 module Enumerable
-  def to_json #:nodoc:
-    "[#{map { |value| ActiveSupport::JSON.encode(value) } * ', '}]"
+  def to_json(options = {}) #:nodoc:
+    "[#{map { |value| ActiveSupport::JSON.encode(value, options) } * ', '}]"
   end
 end

activesupport/lib/active_support/json/encoders/false_class.rb

@@ -1,5 +1,5 @@
 class FalseClass
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     'false'
   end
 end

activesupport/lib/active_support/json/encoders/hash.rb

@@ -1,8 +1,16 @@
 class Hash
-  def to_json #:nodoc:
+  def to_json(options = {}) #:nodoc:
+    hash_keys = self.keys
+
+    if options[:except]
+      hash_keys = hash_keys - Array(options[:except])
+    elsif options[:only]
+      hash_keys = hash_keys & Array(options[:only])
+    end
+
     returning result = '{' do
-      result << map do |key, value|
-        "#{ActiveSupport::JSON.encode(key)}: #{ActiveSupport::JSON.encode(value)}"
+      result << hash_keys.map do |key|
+        "#{ActiveSupport::JSON.encode(key)}: #{ActiveSupport::JSON.encode(self[key], options)}"
       end * ', '
       result << '}'
     end

activesupport/lib/active_support/json/encoders/nil_class.rb

@@ -1,5 +1,5 @@
 class NilClass
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     'null'
   end
 end

activesupport/lib/active_support/json/encoders/numeric.rb

@@ -1,5 +1,5 @@
 class Numeric
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     to_s
   end
 end

activesupport/lib/active_support/json/encoders/object.rb

@@ -1,10 +1,6 @@
 class Object
   # Dumps object in JSON (JavaScript Object Notation).  See www.json.org for more info.
-  #
-  #   Account.find(1).to_json
-  #   => "{attributes: {username: \"foo\", id: \"1\", password: \"bar\"}}"
-  #
-  def to_json
-    ActiveSupport::JSON.encode(instance_values)
+  def to_json(options = {})
+    ActiveSupport::JSON.encode(instance_values, options)
   end
 end

activesupport/lib/active_support/json/encoders/regexp.rb

@@ -1,5 +1,5 @@
 class Regexp
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     inspect
   end
 end

activesupport/lib/active_support/json/encoders/string.rb

@@ -17,7 +17,7 @@ module ActiveSupport
 end
 
 class String
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     '"' + gsub(/[\010\f\n\r\t"\\><]/) { |s|
       ActiveSupport::JSON::Encoding::ESCAPED_CHARS[s]
     }.gsub(/([\xC0-\xDF][\x80-\xBF]|

activesupport/lib/active_support/json/encoders/symbol.rb

@@ -1,5 +1,5 @@
 class Symbol
-  def to_json #:nodoc:
-    ActiveSupport::JSON.encode(to_s)
+  def to_json(options = {}) #:nodoc:
+    ActiveSupport::JSON.encode(to_s, options)
   end
 end

activesupport/lib/active_support/json/encoders/time.rb

@@ -1,5 +1,5 @@
 class Time
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     %("#{strftime("%m/%d/%Y %H:%M:%S %Z")}")
   end
 end

activesupport/lib/active_support/json/encoders/true_class.rb

@@ -1,5 +1,5 @@
 class TrueClass
-  def to_json #:nodoc:
+  def to_json(options = nil) #:nodoc:
     'true'
   end
 end

activesupport/lib/active_support/json/encoding.rb

@@ -17,9 +17,9 @@ module ActiveSupport
       REFERENCE_STACK_VARIABLE = :json_reference_stack #:nodoc:
 
       # Converts a Ruby object into a JSON string.
-      def encode(value)
+      def encode(value, options = {})
         raise_on_circular_reference(value) do
-          value.send(:to_json)
+          value.send(:to_json, options)
         end
       end
 

activesupport/test/json/encoding_test.rb

@@ -69,8 +69,29 @@ class TestJSONEncoding < Test::Unit::TestCase
     assert_equal %w( "$" "A" "A0" "A0B" "_" "a" 0 1 ), object_keys(values.to_json)
   end
 
+  def test_hash_should_allow_key_filtering_with_only
+    assert_equal %({"a": 1}), { 'a' => 1, :b => 2, :c => 3 }.to_json(:only => 'a')
+  end
+
+  def test_hash_should_allow_key_filtering_with_except
+    assert_equal %({"b": 2}), { 'foo' => 'bar', :b => 2, :c => 3 }.to_json(:except => ['foo', :c])
+  end
+
   protected
     def object_keys(json_object)
       json_object[1..-2].scan(/([^{}:,\s]+):/).flatten.sort
     end
 end
+
+uses_mocha 'JsonOptionsTests' do
+  class JsonOptionsTests < Test::Unit::TestCase
+    def test_enumerable_should_passthrough_options_to_elements
+      json_options = { :include => :posts }
+      ActiveSupport::JSON.expects(:encode).with(1, json_options)
+      ActiveSupport::JSON.expects(:encode).with(2, json_options)
+      ActiveSupport::JSON.expects(:encode).with('foo', json_options)
+
+      [1, 2, 'foo'].to_json(json_options)
+    end
+  end
+end