Use thread-safe raw objects for field hashes and arrays

lib/rackstash/fields/abstract_collection.rb

@@ -7,6 +7,8 @@ require 'bigdecimal'
 require 'pathname'
 require 'uri'
 
+require 'concurrent'
+
 module Rackstash
   module Fields
     class AbstractCollection
@@ -101,7 +103,7 @@ module Rackstash
         when Rackstash::Fields::AbstractCollection
           return wrap ? value : value.raw
         when ::Hash
-          hash = value.each_with_object({}) do |(k, v), memo|
+          hash = value.each_with_object(Concurrent::Hash.new) do |(k, v), memo|
             memo[utf8_encode(k)] = normalize(v, scope: scope)
           end
           hash = Rackstash::Fields::Hash.new.tap do |hash_field|
@@ -109,7 +111,9 @@ module Rackstash
           end if wrap
           return hash
         when ::Array, ::Set, ::Enumerator
-          array = value.map { |e| normalize(e, scope: scope) }
+          array = value.each_with_object(Concurrent::Array.new) do |e, memo|
+            memo << normalize(e, scope: scope)
+          end
           array = Rackstash::Fields::Array.new.tap do |array_field|
             array_field.raw = array
           end if wrap

lib/rackstash/fields/array.rb

@@ -9,7 +9,7 @@ module Rackstash
   module Fields
     class Array < AbstractCollection
       def initialize
-        @raw = []
+        @raw = Concurrent::Array.new
       end
 
       # Retrieve a stored value from a given `index`

lib/rackstash/fields/hash.rb

@@ -11,7 +11,7 @@ module Rackstash
       # @param forbidden_keys [Set<String>,Array<String>] a list of strings
       #   which are not allowed to be used as keys in this hash
       def initialize(forbidden_keys: EMPTY_SET)
-        @raw = {}
+        @raw = Concurrent::Hash.new
 
         if forbidden_keys.is_a?(Set)
           forbidden_keys = forbidden_keys.dup.freeze unless forbidden_keys.frozen?

spec/rackstash/fields/array_spec.rb

@@ -56,7 +56,7 @@ describe Rackstash::Fields::Array do
     end
 
     it 'returns a simple array' do
-      expect(array.as_json).to be_a ::Array
+      expect(array.as_json).to be_instance_of ::Array
       expect(array.as_json.length).to eql 3
     end
 
@@ -70,7 +70,7 @@ describe Rackstash::Fields::Array do
     it 'returns a nested array' do
       expect(array[2]).to be_a Rackstash::Fields::Array
 
-      expect(array.as_json[2]).to be_an ::Array
+      expect(array.as_json[2]).to be_instance_of ::Array
       expect(array.as_json[2]).to eql %w[v1 v2]
     end
 

spec/rackstash/fields/hash_spec.rb

@@ -100,21 +100,21 @@ describe Rackstash::Fields::Hash do
     end
 
     it 'returns a simple hash' do
-      expect(hash.as_json).to be_a ::Hash
+      expect(hash.as_json).to be_instance_of ::Hash
       expect(hash.as_json.keys).to eql %w[simple hash array]
     end
 
     it 'returns a nested hash' do
-      expect(hash['hash']).to be_a Rackstash::Fields::Hash
+      expect(hash['hash']).to be_instance_of Rackstash::Fields::Hash
 
-      expect(hash.as_json['hash']).to be_a Hash
+      expect(hash.as_json['hash']).to be_instance_of Hash
       expect(hash.as_json['hash']).to eql 'key' => 'nested value', 'number' => 42
     end
 
     it 'returns a nested array' do
-      expect(hash['array']).to be_a Rackstash::Fields::Array
+      expect(hash['array']).to be_instance_of Rackstash::Fields::Array
 
-      expect(hash.as_json['array']).to be_an ::Array
+      expect(hash.as_json['array']).to be_instance_of ::Array
       expect(hash.as_json['array']).to eql %w[v1 v2]
     end
 
@@ -291,7 +291,7 @@ describe Rackstash::Fields::Hash do
     it 'returns a new object' do
       new_hash = hash.merge(foo: :bar)
 
-      expect(new_hash).to be_a Rackstash::Fields::Hash
+      expect(new_hash).to be_instance_of Rackstash::Fields::Hash
       expect(new_hash).not_to equal hash
 
       # The origiginal hash is not changed
@@ -370,7 +370,7 @@ describe Rackstash::Fields::Hash do
       raw = { :time => Time.now, 'string' => 'foo' }
       hash = Rackstash::Fields::Hash(raw)
 
-      expect(hash).to be_a Rackstash::Fields::Hash
+      expect(hash).to be_instance_of Rackstash::Fields::Hash
       expect(hash['time']).to be_a String
       expect(hash['string']).to eql 'foo'
     end