Remove support for alternate JSON backends

.travis.yml

@@ -17,7 +17,7 @@ matrix:
     - rvm: "1.9"
       gemfile: "gemfiles/Gemfile.json_v1.x"
     - rvm: "2.3.1"
-      gemfile: "gemfiles/Gemfile.multi_json.x"
+      gemfile: "gemfiles/Gemfile.oj.x"
     - rvm: "2.3.1"
       gemfile: "gemfiles/Gemfile.yajl-ruby.x"
     - rvm: "2.3.1"

CHANGELOG.md

@@ -5,6 +5,10 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Changed
+- Support for `multi_json` and `yajl-ruby` have been dropped; the standard `json` library
+  (included in Ruby 1.9+) is always used.
+
 ## [2.7.0] - 2016-09-29
 
 ### Fixed

README.md

@@ -407,25 +407,6 @@ The `JSON::Schema::Reader` interface requires only an object which responds to
 documentation](http://www.rubydoc.info/github/ruby-json-schema/json-schema/master/JSON/Schema/Reader)
 for more information.
 
-JSON Backends
--------------
-
-The JSON Schema library currently supports the `json` and `yajl-ruby` backend
-JSON parsers. If either of these libraries are installed, they will be
-automatically loaded and used to parse any JSON strings supplied by the user.
-
-If more than one of the supported JSON backends are installed, the `yajl-ruby`
-parser is used by default. This can be changed by issuing the following before
-validation:
-
-```ruby
-JSON::Validator.json_backend = :json
-```
-
-Optionally, the JSON Schema library supports using the MultiJSON library for
-selecting JSON backends. If the MultiJSON library is installed, it will be
-autoloaded.
-
 Notes
 -----
 

gemfiles/Gemfile.multi_json.x → gemfiles/Gemfile.oj.x

@@ -2,4 +2,5 @@ source "https://rubygems.org"
 
 gemspec :path => "../"
 
-gem "multi_json"
+gem "oj"
+gem "oj_mimic_json"

gemfiles/Gemfile.yajl-ruby.x

@@ -2,4 +2,4 @@ source "https://rubygems.org"
 
 gemspec :path => "../"
 
-gem "yajl-ruby"
+gem "yajl-ruby", :require => "yajl/json_gem"

lib/json-schema.rb

@@ -1,14 +1,8 @@
 require 'rubygems'
 
-if Gem::Specification::find_all_by_name('multi_json').any?
-  require 'multi_json'
-
-  # Force MultiJson to load an engine before we define the JSON constant here; otherwise,
-  # it looks for things that are under the JSON namespace that aren't there (since we have defined it here)
-  MultiJson.respond_to?(:adapter) ? MultiJson.adapter : MultiJson.engine
-end
-
+require 'json'
 require 'json-schema/util/array_set'
+require 'json-schema/util/parser'
 require 'json-schema/util/uri'
 require 'json-schema/schema'
 require 'json-schema/schema/reader'

lib/json-schema/schema/reader.rb

@@ -91,7 +91,7 @@ def read(location)
                  read_uri(uri)
                end
 
-        JSON::Schema.new(JSON::Validator.parse(body), uri)
+        JSON::Schema.new(JSON::Util::Parser.parse(body), uri)
       end
 
       # @param uri [Addressable::URI]

lib/json-schema/util/parser.rb

@@ -0,0 +1,17 @@
+module JSON
+  module Util
+    module Parser
+      def self.parse(string)
+        begin
+          JSON.parse(string, :quirks_mode => true)
+        rescue JSON::ParserError => e
+          raise JSON::Schema::JsonParseError.new(e.message)
+        end
+      end
+
+      def self.serialize(hash)
+        JSON.dump(hash)
+      end
+    end
+  end
+end

lib/json-schema/validator.rb

@@ -32,9 +32,6 @@ class Validator
     }
     @@validators = {}
     @@default_validator = nil
-    @@available_json_backends = []
-    @@json_backend = nil
-    @@serializer = nil
     @@mutex = Mutex.new
 
     def initialize(schema_data, data, opts={})
@@ -388,54 +385,17 @@ def restore_default_formats(versions = ["draft1", "draft2", "draft3", "draft4",
       end
 
       def json_backend
-        if defined?(MultiJson)
-          MultiJson.respond_to?(:adapter) ? MultiJson.adapter : MultiJson.engine
-        else
-          @@json_backend
-        end
+        warn "[DEPRECATION NOTICE] Alternate JSON backends for json-schema are no longer used. If you would like to use a non-standard JSON backend, please use it in compatibility mode."
+        nil
       end
 
       def json_backend=(backend)
-        if defined?(MultiJson)
-          backend = backend == 'json' ? 'json_gem' : backend
-          MultiJson.respond_to?(:use) ? MultiJson.use(backend) : MultiJson.engine = backend
-        else
-          backend = backend.to_s
-          if @@available_json_backends.include?(backend)
-            @@json_backend = backend
-          else
-            raise JSON::Schema::JsonParseError.new("The JSON backend '#{backend}' could not be found.")
-          end
-        end
+        warn "[DEPRECATION NOTICE] Alternate JSON backends for json-schema are no longer used. If you would like to use a non-standard JSON backend, please use it in compatibility mode."
       end
 
-      def parse(s)
-        if defined?(MultiJson)
-          begin
-            MultiJson.respond_to?(:adapter) ? MultiJson.load(s) : MultiJson.decode(s)
-          rescue MultiJson::ParseError => e
-            raise JSON::Schema::JsonParseError.new(e.message)
-          end
-        else
-          case @@json_backend.to_s
-          when 'json'
-            begin
-              JSON.parse(s, :quirks_mode => true)
-            rescue JSON::ParserError => e
-              raise JSON::Schema::JsonParseError.new(e.message)
-            end
-          when 'yajl'
-            begin
-              json = StringIO.new(s)
-              parser = Yajl::Parser.new
-              parser.parse(json) or raise JSON::Schema::JsonParseError.new("The JSON could not be parsed by yajl")
-            rescue Yajl::ParseError => e
-              raise JSON::Schema::JsonParseError.new(e.message)
-            end
-          else
-            raise JSON::Schema::JsonParseError.new("No supported JSON parsers found. The following parsers are suported:\n * yajl-ruby\n * json")
-          end
-        end
+      def parse(string)
+        warn "[DEPRECATION NOTICE] JSON::Validator#parse has been moved to JSON::Util::Parser."
+        JSON::Util::Parser.parse(string)
       end
 
       def merge_missing_values(source, destination)
@@ -457,37 +417,6 @@ def merge_missing_values(source, destination)
         end
       end
 
-      if !defined?(MultiJson)
-        if Gem::Specification::find_all_by_name('json').any?
-          require 'json'
-          @@available_json_backends << 'json'
-          @@json_backend = 'json'
-        else
-          # Try force-loading json for rubies > 1.9.2
-          begin
-            require 'json'
-            @@available_json_backends << 'json'
-            @@json_backend = 'json'
-          rescue LoadError
-          end
-        end
-
-
-        if Gem::Specification::find_all_by_name('yajl-ruby').any?
-          require 'yajl'
-          @@available_json_backends << 'yajl'
-          @@json_backend = 'yajl'
-        end
-
-        if @@json_backend == 'yajl'
-          @@serializer = lambda{|o| Yajl::Encoder.encode(o) }
-        elsif @@json_backend == 'json'
-          @@serializer = lambda{|o| JSON.dump(o) }
-        else
-          @@serializer = lambda{|o| YAML.dump(o) }
-        end
-      end
-
       private
 
       def validators_for_names(names)
@@ -515,12 +444,9 @@ def validators_for_names(names)
       @@fake_uuid_generator = lambda{|s| JSON::Util::UUID.create_v5(s,JSON::Util::UUID::Nil).to_s }
     end
 
-    def serialize schema
-      if defined?(MultiJson)
-        MultiJson.respond_to?(:dump) ? MultiJson.dump(schema) : MultiJson.encode(schema)
-      else
-        @@serializer.call(schema)
-      end
+    def serialize(schema)
+      warn "[DEPRECATION NOTICE] JSON::Validator#serialize has been moved to JSON::Util::Parser."
+      JSON::Util::Parser.serialize(schema)
     end
 
     def fake_uuid schema
@@ -532,7 +458,7 @@ def initialize_schema(schema)
         begin
           # Build a fake URI for this
           schema_uri = JSON::Util::URI.parse(fake_uuid(schema))
-          schema = JSON::Schema.new(JSON::Validator.parse(schema), schema_uri, @options[:version])
+          schema = JSON::Schema.new(JSON::Util::Parser.parse(schema), schema_uri, @options[:version])
           if @options[:list] && @options[:fragment].nil?
             schema = schema.to_array_schema
           end
@@ -553,14 +479,14 @@ def initialize_schema(schema)
             schema = self.class.schema_for_uri(schema_uri)
             if @options[:list] && @options[:fragment].nil?
               schema = schema.to_array_schema
-              schema.uri = JSON::Util::URI.parse(fake_uuid(serialize(schema.schema)))
+              schema.uri = JSON::Util::URI.parse(fake_uuid(JSON::Util::Parser.serialize(schema.schema)))
               Validator.add_schema(schema)
             end
             schema
           end
         end
       elsif schema.is_a?(Hash)
-        schema_uri = JSON::Util::URI.parse(fake_uuid(serialize(schema)))
+        schema_uri = JSON::Util::URI.parse(fake_uuid(JSON::Util::Parser.serialize(schema)))
         schema = JSON::Schema.stringify(schema)
         schema = JSON::Schema.new(schema, schema_uri, @options[:version])
         if @options[:list] && @options[:fragment].nil?
@@ -577,17 +503,17 @@ def initialize_schema(schema)
     def initialize_data(data)
       if @options[:parse_data]
         if @options[:json]
-          data = JSON::Validator.parse(data)
+          data = JSON::Util::Parser.parse(data)
         elsif @options[:uri]
           json_uri = Util::URI.normalized_uri(data)
-          data = JSON::Validator.parse(custom_open(json_uri))
+          data = JSON::Util::Parser.parse(custom_open(json_uri))
         elsif data.is_a?(String)
           begin
-            data = JSON::Validator.parse(data)
+            data = JSON::Util::Parser.parse(data)
           rescue JSON::Schema::JsonParseError
             begin
               json_uri = Util::URI.normalized_uri(data)
-              data = JSON::Validator.parse(custom_open(json_uri))
+              data = JSON::Util::Parser.parse(custom_open(json_uri))
             rescue JSON::Schema::JsonLoadError
               # Silently discard the error - use the data as-is
             end

test/files_test.rb

@@ -2,10 +2,6 @@
 
 class FilesTest < Minitest::Test
 
-  #
-  # These tests are ONLY run if there is an appropriate JSON backend parser available
-  #
-
   def test_schema_from_file
     assert_valid schema_fixture_path('good_schema_1.json'), { "a" => 5 }
     refute_valid schema_fixture_path('good_schema_1.json'), { "a" => "bad" }