refactor: replace multi_json with stdlib json

Author: eglitobias

hutch.gemspec

@@ -9,7 +9,6 @@ Gem::Specification.new do |gem|
     gem.add_runtime_dependency 'bunny', '>= 3.1', '< 4.0'
   end
   gem.add_runtime_dependency 'carrot-top', '~> 0.0.7'
-  gem.add_runtime_dependency 'multi_json', '~> 1.15'
   gem.add_runtime_dependency 'activesupport', '>= 4.2'
 
   gem.name = 'hutch'

lib/hutch/serializers/json.rb

@@ -1,16 +1,16 @@
-require 'multi_json'
+ require 'json'
 require 'active_support/core_ext/hash/indifferent_access'
 
 module Hutch
   module Serializers
     class JSON
 
       def self.encode(payload)
-        ::MultiJson.dump(payload)
+        ::JSON.generate(payload)
       end
 
       def self.decode(payload)
-        ::MultiJson.load(payload).with_indifferent_access
+        ::JSON.parse(payload).with_indifferent_access
       end
 
       def self.binary? ; false ; end

spec/hutch/message_spec.rb

@@ -4,7 +4,7 @@
   let(:delivery_info) { double('Delivery Info') }
   let(:props) { double('Properties', content_type: "application/json") }
   let(:body) {{ foo: 'bar' }.with_indifferent_access}
-  let(:json_body) { MultiJson.dump(body) }
+  let(:json_body) { JSON.generate(body) }
   subject(:message) { Hutch::Message.new(delivery_info, props, json_body, Hutch::Config[:serializer]) }
 
   describe '#body' do

spec/hutch/worker_spec.rb

@@ -191,7 +191,7 @@ def handle(_properties, _payload, _consumer, _ex)
 
     context "when the payload is not valid json" do
       let(:payload) { "Not Valid JSON" }
-      let(:expected_log) { /ERROR .+ error in consumer .+ MultiJson::ParseError .+ backtrace:/m }
+      let(:expected_log) { /ERROR .+ error in consumer .+ JSON::ParserError .+ backtrace:/m }
 
       it 'logs the error' do
         expect { subject }.to change { log.tap(&:rewind).read }.from("").to(expected_log)