Add support for Postgres Range Types

CHANGELOG.md

@@ -77,7 +77,7 @@ recommendations of [keepachangelog.com](http://keepachangelog.com/).
 
 ### Fixed
 
-- None
+- Fixed errors when deserializing Range types from Ruby style strings to Postgres
 
 ## 15.1.0 (2023-10-22)
 

lib/paper_trail/attribute_serializers/attribute_serializer_factory.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "paper_trail/type_serializers/postgres_array_serializer"
+require "paper_trail/type_serializers/postgres_range_serializer"
 
 module PaperTrail
   module AttributeSerializers
@@ -13,13 +14,18 @@ module AttributeSerializers
     module AttributeSerializerFactory
       class << self
         # @api private
-        def for(klass, attr)
-          active_record_serializer = klass.type_for_attribute(attr)
+        def for(model_class, attr)
+          active_record_serializer = model_class.type_for_attribute(attr)
+
           if ar_pg_array?(active_record_serializer)
             TypeSerializers::PostgresArraySerializer.new(
               active_record_serializer.subtype,
               active_record_serializer.delimiter
             )
+          elsif ar_pg_range?(active_record_serializer)
+            TypeSerializers::PostgresRangeSerializer.new(
+              active_record_serializer
+            )
           else
             active_record_serializer
           end
@@ -35,6 +41,15 @@ def ar_pg_array?(obj)
             false
           end
         end
+
+        # @api private
+        def ar_pg_range?(obj)
+          if defined?(::ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Range)
+            obj.instance_of?(::ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Range)
+          else
+            false
+          end
+        end
       end
     end
   end

lib/paper_trail/attribute_serializers/cast_attribute_serializer.rb

@@ -9,8 +9,8 @@ module AttributeSerializers
     # example, the string "1.99" serializes into the integer `1` when assigned
     # to an attribute of type `ActiveRecord::Type::Integer`.
     class CastAttributeSerializer
-      def initialize(klass)
-        @klass = klass
+      def initialize(model_class)
+        @model_class = model_class
       end
 
       private
@@ -25,7 +25,8 @@ def initialize(klass)
       # ActiveRecord::Enum was added in AR 4.1
       # http://edgeguides.rubyonrails.org/4_1_release_notes.html#active-record-enums
       def defined_enums
-        @defined_enums ||= (@klass.respond_to?(:defined_enums) ? @klass.defined_enums : {})
+        @defined_enums ||=
+          @model_class.respond_to?(:defined_enums) ? @model_class.defined_enums : {}
       end
 
       def deserialize(attr, val)
@@ -39,12 +40,12 @@ def deserialize(attr, val)
           # https://github.com/rails/rails/issues/43966
           val.instance_variable_get(:@time)
         else
-          AttributeSerializerFactory.for(@klass, attr).deserialize(val)
+          AttributeSerializerFactory.for(@model_class, attr).deserialize(val)
         end
       end
 
       def serialize(attr, val)
-        AttributeSerializerFactory.for(@klass, attr).serialize(val)
+        AttributeSerializerFactory.for(@model_class, attr).serialize(val)
       end
     end
   end

lib/paper_trail/attribute_serializers/object_attribute.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require "paper_trail/attribute_serializers/cast_attribute_serializer"
+require "paper_trail/type_serializers/postgres_range_serializer"
 
 module PaperTrail
   module AttributeSerializers
@@ -26,10 +27,7 @@ def deserialize(attributes)
       # Modifies `attributes` in place.
       # TODO: Return a new hash instead.
       def alter(attributes, serialization_method)
-        # Don't serialize non-encrypted before values before inserting into columns of type
-        # `JSON` on `PostgreSQL` databases.
-        attributes_to_serialize =
-          object_col_is_json? ? attributes.slice(*@encrypted_attributes) : attributes
+        attributes_to_serialize = attributes_to_serialize(attributes)
         return attributes if attributes_to_serialize.blank?
 
         serializer = CastAttributeSerializer.new(@model_class)
@@ -40,6 +38,24 @@ def alter(attributes, serialization_method)
         attributes
       end
 
+      # Don't de/serialize non-encrypted before values before inserting into columns of type
+      # `JSON` on `PostgreSQL` databases; Unless it's a special type like a range.
+      def attributes_to_serialize(attributes)
+        encrypted_to_serialize = if object_col_is_json?
+                                   attributes.slice(*@encrypted_attributes)
+                                 else
+                                   attributes
+                                 end
+
+        columns_to_serialize = attributes.select { |column, _|
+          TypeSerializers::PostgresRangeSerializer.range_type?(
+            @model_class.columns_hash[column]&.type
+          )
+        }
+
+        encrypted_to_serialize.merge(columns_to_serialize)
+      end
+
       def object_col_is_json?
         @model_class.paper_trail.version_class.object_col_is_json?
       end

lib/paper_trail/attribute_serializers/object_changes_attribute.rb

@@ -1,16 +1,17 @@
 # frozen_string_literal: true
 
 require "paper_trail/attribute_serializers/cast_attribute_serializer"
+require "paper_trail/type_serializers/postgres_range_serializer"
 
 module PaperTrail
   module AttributeSerializers
     # Serialize or deserialize the `version.object_changes` column.
     class ObjectChangesAttribute
-      def initialize(item_class)
-        @item_class = item_class
+      def initialize(model_class)
+        @model_class = model_class
 
         # ActiveRecord since 7.0 has a built-in encryption mechanism
-        @encrypted_attributes = @item_class.encrypted_attributes&.map(&:to_s)
+        @encrypted_attributes = @model_class.encrypted_attributes&.map(&:to_s)
       end
 
       def serialize(changes)
@@ -26,13 +27,10 @@ def deserialize(changes)
       # Modifies `changes` in place.
       # TODO: Return a new hash instead.
       def alter(changes, serialization_method)
-        # Don't serialize non-encrypted before values before inserting into columns of type
-        # `JSON` on `PostgreSQL` databases.
-        changes_to_serialize =
-          object_changes_col_is_json? ? changes.slice(*@encrypted_attributes) : changes.clone
+        changes_to_serialize = changes_to_serialize(changes)
         return changes if changes_to_serialize.blank?
 
-        serializer = CastAttributeSerializer.new(@item_class)
+        serializer = CastAttributeSerializer.new(@model_class)
         changes_to_serialize.each do |key, change|
           # `change` is an Array with two elements, representing before and after.
           changes[key] = Array(change).map do |value|
@@ -43,8 +41,26 @@ def alter(changes, serialization_method)
         changes
       end
 
+      # Don't de/serialize non-encrypted before values before inserting into columns of type
+      # `JSON` on `PostgreSQL` databases; Unless it's a special type like a range.
+      def changes_to_serialize(changes)
+        encrypted_to_serialize = if object_changes_col_is_json?
+                                   changes.slice(*@encrypted_attributes)
+                                 else
+                                   changes.clone
+                                 end
+
+        columns_to_serialize = changes.select { |column, _|
+          TypeSerializers::PostgresRangeSerializer.range_type?(
+            @model_class.columns_hash[column]&.type
+          )
+        }
+
+        encrypted_to_serialize.merge(columns_to_serialize)
+      end
+
       def object_changes_col_is_json?
-        @item_class.paper_trail.version_class.object_changes_col_is_json?
+        @model_class.paper_trail.version_class.object_changes_col_is_json?
       end
     end
   end

lib/paper_trail/type_serializers/postgres_range_serializer.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+module PaperTrail
+  module TypeSerializers
+    # Provides an alternative method of serialization
+    # and deserialization of PostgreSQL range columns.
+    class PostgresRangeSerializer
+      # @see https://github.com/rails/rails/blob/main/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb#L147-L152
+      RANGE_TYPES = %i[
+        daterange
+        numrange
+        tsrange
+        tstzrange
+        int4range
+        int8range
+      ].freeze
+
+      def self.range_type?(type)
+        RANGE_TYPES.include?(type)
+      end
+
+      def initialize(active_record_serializer)
+        @active_record_serializer = active_record_serializer
+      end
+
+      def serialize(range)
+        range
+      end
+
+      def deserialize(range)
+        range.is_a?(String) ? deserialize_with_ar(range) : range
+      end
+
+      private
+
+      def deserialize_with_ar(string)
+        return nil if string.blank?
+
+        delimiter = string[/\.{2,3}/]
+        range_start, range_end = string.split(delimiter)
+
+        range_start = @active_record_serializer.subtype.cast(range_start)
+        range_end   = @active_record_serializer.subtype.cast(range_end)
+
+        Range.new(range_start, range_end, exclude_end: delimiter == "...")
+      end
+    end
+  end
+end

spec/paper_trail/attribute_serializers/object_attribute_spec.rb

@@ -8,15 +8,21 @@ module AttributeSerializers
       if ENV["DB"] == "postgres"
         describe "postgres-specific column types" do
           describe "#serialize" do
-            it "serializes a postgres array into a plain array" do
+            it "serializes a postgres array into a ruby array" do
               attrs = { "post_ids" => [1, 2, 3] }
               described_class.new(PostgresUser).serialize(attrs)
               expect(attrs["post_ids"]).to eq [1, 2, 3]
             end
+
+            it "serializes a postgres range into a ruby array" do
+              attrs = { "range" => 1..5 }
+              described_class.new(PostgresUser).serialize(attrs)
+              expect(attrs["range"]).to eq 1..5
+            end
           end
 
           describe "#deserialize" do
-            it "deserializes a plain array correctly" do
+            it "deserializes a ruby array correctly" do
               attrs = { "post_ids" => [1, 2, 3] }
               described_class.new(PostgresUser).deserialize(attrs)
               expect(attrs["post_ids"]).to eq [1, 2, 3]
@@ -37,6 +43,12 @@ module AttributeSerializers
               described_class.new(PostgresUser).deserialize(attrs)
               expect(attrs["post_ids"]).to eq [date1, date2, date3]
             end
+
+            it "deserializes a ruby range correctly" do
+              attrs = { "range" => 1..5 }
+              described_class.new(PostgresUser).deserialize(attrs)
+              expect(attrs["range"]).to eq 1..5
+            end
           end
         end
       end

spec/paper_trail/type_serializers/postgres_range_serializer_spec.rb

@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+
+module PaperTrail
+  module TypeSerializers
+    ::RSpec.describe PostgresRangeSerializer do
+      if ENV["DB"] == "postgres"
+        let(:active_record_serializer) {
+          ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Range.new(subtype)
+        }
+        let(:serializer) { described_class.new(active_record_serializer) }
+
+        describe ".deserialize" do
+          let(:range_string) { range_ruby.to_s }
+
+          context "with daterange" do
+            let(:subtype) { ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Date.new }
+            let(:range_ruby) { Date.new(2024, 1, 1)..Date.new(2024, 1, 31) }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+
+            context "with exclude_end" do
+              let(:range_ruby) { Date.new(2024, 1, 1)...Date.new(2024, 1, 31) }
+
+              it "deserializes to Ruby" do
+                expect(serializer.deserialize(range_string)).to eq(range_ruby)
+              end
+            end
+          end
+
+          context "with numrange" do
+            let(:subtype) { ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Decimal.new }
+            let(:range_ruby) { 1.5..3.5 }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+          end
+
+          context "with tsrange" do
+            let(:subtype) { ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Timestamp.new }
+            let(:range_ruby) { 1.day.ago..1.day.from_now }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+          end
+
+          context "with tstzrange" do
+            let(:subtype) {
+              ActiveRecord::ConnectionAdapters::PostgreSQL::OID::TimestampWithTimeZone.new
+            }
+            let(:range_ruby) { Date.new(2021, 1, 1)..Date.new(2021, 1, 31) }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+          end
+
+          context "with int4range" do
+            let(:subtype) { ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Integer.new }
+            let(:range_ruby) { 1..10 }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+          end
+
+          context "with int8range" do
+            let(:subtype) { ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Integer.new }
+            let(:range_ruby) { 2_200_000_000..2_500_000_000 }
+
+            it "deserializes to Ruby" do
+              expect(serializer.deserialize(range_string)).to eq(range_ruby)
+            end
+          end
+        end
+      end
+    end
+  end
+end