move symbolize_keys to Propono namespace

* behaviour is quirky and conflicts with e.g. ActiveSupport implementation
* retained Propono implementation rather than depend on yet another library, but don't mixin with Hash
* change impact: anyone inheriting Hash#symbolise_keys from Propono and using elsewhere in their projects would need to decide to use another library for symbolize_keys, or use Propono::Utils.symbolize_keys explicitly

Rakefile

@@ -11,7 +11,7 @@ end
 
 namespace :test do
   Rake::TestTask.new(:local) do |t|
-    t.pattern = "test/{components/,services/,helpers/,}*_test.rb"
+    t.pattern = "test/{components/,services/,utils/,}*_test.rb"
   end
 end
 

lib/propono.rb

@@ -5,8 +5,7 @@
 require 'propono/propono_error'
 require 'propono/logger'
 require 'propono/configuration'
-
-require "propono/helpers/hash"
+require "propono/utils"
 
 require 'propono/components/aws_config'
 require 'propono/components/sns'

lib/propono/components/sqs_message.rb

@@ -9,7 +9,7 @@ def initialize(raw_message)
       body = JSON.parse(@raw_body_json["Message"])
 
       @raw_message    = raw_message
-      @context        = body.symbolize_keys
+      @context        = Propono::Utils.symbolize_keys body
       @failure_count  = context[:num_failures] || 0
       @message        = context.delete(:message)
       @receipt_handle = raw_message["receipt_handle"]

lib/propono/services/publisher.rb

@@ -17,7 +17,7 @@ def initialize(topic_id, message, options = {})
       raise PublisherError.new("Topic is nil") if topic_id.nil?
       raise PublisherError.new("Message is nil") if message.nil?
 
-      options = options.symbolize_keys
+      options = Propono::Utils.symbolize_keys options
 
       @topic_id = topic_id
       @message = message

lib/propono/services/tcp_listener.rb

@@ -29,7 +29,7 @@ def receive_and_process
     end
 
     def process_tcp_data(tcp_data)
-      json = JSON.parse(tcp_data).symbolize_keys
+      json = Propono::Utils.symbolize_keys JSON.parse(tcp_data)
 
       # Legacy syntax is covered in the else statement
       # This conditional and the else block will be removed in v1.

lib/propono/services/udp_listener.rb

@@ -27,7 +27,7 @@ def receive_and_process
     end
 
     def process_udp_data(udp_data)
-      json = JSON.parse(udp_data).symbolize_keys
+      json = Propono::Utils.symbolize_keys JSON.parse(udp_data)
 
       # Legacy syntax is covered in the else statement
       # This conditional and the else block will be removed in v1.

lib/propono/utils.rb

@@ -0,0 +1,17 @@
+module Propono
+  module Utils
+
+    # Returns +hash+ with all primary and nested keys to string values symbolised
+    # To avoid conflicts with ActiveSupport and other libraries that provide Hash symbolisation,
+    # this method is kept within the Propono namespace and not mixed into Hash
+    def self.symbolize_keys(hash)
+      hash.inject({}) do |result, (key, value)|
+        new_key = key.is_a?(String) ? key.to_sym : key
+        new_value = value.is_a?(Hash) ? symbolize_keys(value) : value
+        result[new_key] = new_value
+        result
+      end
+    end
+
+  end
+end

test/helpers/hash_test.rb → test/utils/hash_test.rb

@@ -22,7 +22,7 @@ def test_symbolize_keys_works
         }
       }
 
-      assert_equal expected, input.symbolize_keys
+      assert_equal expected, Propono::Utils.symbolize_keys(input)
     end
   end
 end