Adding JSON serializer to the gem. Close #194

CHANGELOG.md

@@ -1,9 +1,10 @@
 ## 2.7.1 (Unreleased)
 
+  - [#194](https://github.com/airblade/paper_trail/issues/194) - A JSON serializer is now included in the gem.
   - [#192](https://github.com/airblade/paper_trail/pull/192) - `object_changes` should store serialized representation of serialized
     attributes for `create` actions (in addition to `update` actions, which had already been patched by
     [#180](https://github.com/airblade/paper_trail/pull/180)).
-  - [#190](https://github.com/airblade/paper_trail/pull/190) - Fix compatibility with
+  - [#190](https://github.com/airblade/paper_trail/pull/190) - Fixed compatibility with
     [SerializedAttributes](https://github.com/technoweenie/serialized_attributes) gem.
   - [#189](https://github.com/airblade/paper_trail/pull/189) - Provided support for a `configure` block initializer.
   - Added `setter` method for the `serializer` config option.

README.md

@@ -749,7 +749,10 @@ By default, PaperTrail stores your changes as a YAML dump. You can override this
 >> PaperTrail.config.serializer = MyCustomSerializer
 ```
 
-The serializer needs to be a class that responds to a `load` and `dump` method.  [See the default PaperTrail serializer](https://github.com/airblade/paper_trail/blob/master/lib/paper_trail/serializers/yaml.rb) for an example.
+The serializer needs to be a class that has a `load` and `dump` class method.  These serializers are included in the gem for your convenience:
+
+* [Yaml](https://github.com/airblade/paper_trail/blob/master/lib/paper_trail/serializers/yaml.rb) - Default
+* [Json](https://github.com/airblade/paper_trail/blob/master/lib/paper_trail/serializers/json.rb)
 
 ## Deleting Old Versions
 

lib/paper_trail.rb

@@ -2,7 +2,9 @@ require 'paper_trail/config'
 require 'paper_trail/controller'
 require 'paper_trail/has_paper_trail'
 require 'paper_trail/version'
+
 require 'paper_trail/serializers/yaml'
+require 'paper_trail/serializers/json'
 
 # PaperTrail's module methods can be called in both models and controllers.
 module PaperTrail

lib/paper_trail/serializers/json.rb

@@ -0,0 +1,15 @@
+require 'active_support/json'
+
+module PaperTrail
+  module Serializers
+    class Json
+      def self.load(string)
+        ActiveSupport::JSON.decode string
+      end
+
+      def self.dump(hash)
+        ActiveSupport::JSON.encode hash
+      end
+    end
+  end
+end

paper_trail.gemspec

@@ -19,7 +19,8 @@ Gem::Specification.new do |s|
   s.add_dependency 'activerecord', '~> 3.0'
 
   s.add_development_dependency 'rake'
-  s.add_development_dependency 'shoulda',      '~> 3.3'
-  s.add_development_dependency 'sqlite3',      '~> 1.2'
-  s.add_development_dependency 'capybara',     '~> 2.0'
+  s.add_development_dependency 'shoulda', '~> 3.3'
+  s.add_development_dependency 'sqlite3', '~> 1.2'
+  s.add_development_dependency 'capybara', '~> 2.0'
+  s.add_development_dependency 'ffaker', '>= 1.15'
 end

test/test_helper.rb

@@ -11,6 +11,7 @@ require "rails/test_help"
 Rails.backtrace_cleaner.remove_silencers!
 
 require 'shoulda'
+require 'ffaker'
 
 # Configure capybara for integration testing
 require "capybara/rails"

test/unit/serializer_test.rb

@@ -1,16 +1,5 @@
 require 'test_helper'
 
-class CustomSerializer
-  require 'json'
-  def self.dump(object_hash)
-    JSON.dump object_hash
-  end
-
-  def self.load(string)
-    JSON.parse string
-  end
-end
-
 class SerializerTest < ActiveSupport::TestCase
 
   context 'YAML Serializer' do
@@ -40,7 +29,7 @@ class SerializerTest < ActiveSupport::TestCase
   context 'Custom Serializer' do
     setup do
       PaperTrail.configure do |config|
-        config.serializer = CustomSerializer
+        config.serializer = PaperTrail::Serializers::Json
       end
 
       Fluxor.instance_eval <<-END

test/unit/serializers/json_test.rb

@@ -0,0 +1,42 @@
+require 'test_helper'
+
+class JsonTest < ActiveSupport::TestCase
+
+  setup do
+    # Setup a hash with random values
+    @hash = {}
+    (1..4).each do |i|
+      @hash["key#{i}"] = Faker::Lorem.word
+    end
+    @hash_as_json = @hash.to_json
+    # Setup an array of random words
+    @array = []
+    (4..8).to_a.sample.times do
+      @array << Faker::Lorem.word
+    end
+    @array_as_json = @array.to_json
+  end
+
+  context '`load` class method' do
+    should 'exist' do
+      assert PaperTrail::Serializers::Json.respond_to?(:load)
+    end
+
+    should '`deserialize` JSON to Ruby' do
+      assert_equal @hash, PaperTrail::Serializers::Json.load(@hash_as_json)
+      assert_equal @array, PaperTrail::Serializers::Json.load(@array_as_json)
+    end
+  end
+
+  context '`dump` class method' do
+    should 'exist' do
+      assert PaperTrail::Serializers::Json.respond_to?(:dump)
+    end
+
+    should '`deserialize` JSON to Ruby' do
+      assert_equal @hash_as_json, PaperTrail::Serializers::Json.dump(@hash)
+      assert_equal @array_as_json, PaperTrail::Serializers::Json.dump(@array)
+    end
+  end
+
+end

test/unit/serializers/yaml_test.rb

@@ -0,0 +1,42 @@
+require 'test_helper'
+
+class YamlTest < ActiveSupport::TestCase
+
+  setup do
+    # Setup a hash with random values
+    @hash = {}
+    (1..4).each do |i|
+      @hash["key#{i}".to_sym] = Faker::Lorem.word
+    end
+    @hash_as_yaml = @hash.to_yaml
+    # Setup an array of random words
+    @array = []
+    (4..8).to_a.sample.times do
+      @array << Faker::Lorem.word
+    end
+    @array_as_yaml = @array.to_yaml
+  end
+
+  context '`load` class method' do
+    should 'exist' do
+      assert PaperTrail::Serializers::Yaml.respond_to?(:load)
+    end
+
+    should '`deserialize` YAML to Ruby' do
+      assert_equal @hash, PaperTrail::Serializers::Yaml.load(@hash_as_yaml)
+      assert_equal @array, PaperTrail::Serializers::Yaml.load(@array_as_yaml)
+    end
+  end
+
+  context '`dump` class method' do
+    should 'exist' do
+      assert PaperTrail::Serializers::Yaml.respond_to?(:dump)
+    end
+
+    should '`deserialize` YAML to Ruby' do
+      assert_equal @hash_as_yaml, PaperTrail::Serializers::Yaml.dump(@hash)
+      assert_equal @array_as_yaml, PaperTrail::Serializers::Yaml.dump(@array)
+    end
+  end
+
+end