Typecasting data when inserting into Redis (#22)

* use ActiveModel::Types to cast the values in Redis to their type

* cast values to type before storing in redis to ensure that they are valid and have been formatted correctly.

* Remove extra CR

* Remove extra CR

* add floats to the types for the attributes api

* cast floats as floats and not decimals

* require inclusiion before using presence_in

* only cast the valuees of the hash type

* add a test for the float type. Update decimal test to reflect that it is being cast to a decimal instead of a float.

Co-authored-by: David Heinemeier Hansson <[email protected]>

Author: lsylvester

lib/kredis/attributes.rb

@@ -30,6 +30,10 @@ def kredis_flag(name, key: nil, config: :shared, after_change: nil)
       end
     end
 
+    def kredis_float(name, key: nil, config: :shared, after_change: nil)
+      kredis_connection_with __method__, name, key, config: config, after_change: after_change
+    end
+
     def kredis_enum(name, key: nil, values:, default:, config: :shared, after_change: nil)
       kredis_connection_with __method__, name, key, values: values, default: default, config: config, after_change: after_change
     end

lib/kredis/type/datetime.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Kredis
+  module Type
+    class DateTime < ActiveModel::Type::DateTime
+      def serialize(value)
+        super&.iso8601(9)
+      end
+
+      def cast_value(value)
+        super&.to_datetime
+      end
+    end
+  end
+end

lib/kredis/type/json.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+module Kredis
+  module Type
+    class Json < ActiveModel::Type::Value
+      def type
+        :json
+      end
+
+      def cast_value(value)
+        JSON.load(value)
+      end
+
+      def serialize(value)
+        JSON.dump(value)
+      end
+    end
+  end
+end

lib/kredis/type_casting.rb

@@ -1,47 +1,35 @@
 require "json"
+require "active_model/type"
+require "kredis/type/json"
+require "kredis/type/datetime"
 
 module Kredis::TypeCasting
   class InvalidType < StandardError; end
 
-  VALID_TYPES = %i[ string integer decimal float boolean datetime json ]
-
-  def type_to_string(value)
-    case value
-    when nil
-      ""
-    when Integer
-      value.to_s
-    when BigDecimal
-      value.to_d
-    when Float
-      value.to_s
-    when TrueClass, FalseClass
-      value ? "t" : "f"
-    when Time, DateTime, ActiveSupport::TimeWithZone
-      value.iso8601(9)
-    when Hash
-      JSON.dump(value)
-    else
-      value
-    end
+  TYPES = {
+    string: ActiveModel::Type::String.new,
+    integer: ActiveModel::Type::Integer.new,
+    decimal: ActiveModel::Type::Decimal.new,
+    float: ActiveModel::Type::Float.new,
+    boolean: ActiveModel::Type::Boolean.new,
+    datetime: Kredis::Type::DateTime.new,
+    json: Kredis::Type::Json.new
+  }
+
+  def type_to_string(value, type)
+    raise InvalidType if type && !TYPES.key?(type)
+
+    TYPES[type || :string].serialize(value)
   end
 
   def string_to_type(value, type)
-    raise InvalidType if type && !VALID_TYPES.include?(type)
-
-    case type
-    when nil, :string then value
-    when :integer     then value.to_i
-    when :decimal     then value.to_d
-    when :float       then value.to_f
-    when :boolean     then value == "t" ? true : false
-    when :datetime    then Time.iso8601(value)
-    when :json        then JSON.load(value)
-    end if value.present?
+    raise InvalidType if type && !TYPES.key?(type)
+
+    TYPES[type || :string].cast(value)
   end
 
-  def types_to_strings(values)
-    Array(values).flatten.map { |value| type_to_string(value) }
+  def types_to_strings(values, type)
+    Array(values).flatten.map { |value| type_to_string(value, type) }
   end
 
   def strings_to_types(values, type)

lib/kredis/types/enum.rb

@@ -1,3 +1,5 @@
+require "active_support/core_ext/object/inclusion"
+
 class Kredis::Types::Enum < Kredis::Types::Proxying
   proxying :set, :get, :del
 

lib/kredis/types/hash.rb

@@ -13,21 +13,20 @@ def []=(key, value)
     update key => value
   end
 
-
   def update(**entries)
-    hset types_to_strings(entries) if entries.flatten.any?
+    hset entries.transform_values{ |val| type_to_string(val, typed) } if entries.flatten.any?
   end
 
   def values_at(*keys)
     strings_to_types(hmget(keys) || [], typed)
   end
 
   def delete(*keys)
-    hdel types_to_strings(keys) if keys.flatten.any?
+    hdel keys if keys.flatten.any?
   end
 
   def remove
-    del 
+    del
   end
 
   def entries

lib/kredis/types/list.rb

@@ -9,15 +9,15 @@ def elements
   alias to_a elements
 
   def remove(*elements)
-    types_to_strings(elements).each { |element| lrem 0, element }
+    types_to_strings(elements, typed).each { |element| lrem 0, element }
   end
 
   def prepend(*elements)
-    lpush types_to_strings(elements) if elements.flatten.any?
+    lpush types_to_strings(elements, typed) if elements.flatten.any?
   end
 
   def append(*elements)
-    rpush types_to_strings(elements) if elements.flatten.any?
+    rpush types_to_strings(elements, typed) if elements.flatten.any?
   end
   alias << append
 end

lib/kredis/types/scalar.rb

@@ -4,12 +4,12 @@ class Kredis::Types::Scalar < Kredis::Types::Proxying
   attr_accessor :typed, :default, :expires_in
 
   def value=(value)
-    set type_to_string(value), ex: expires_in
+    set type_to_string(value, typed), ex: expires_in
   end
 
   def value
     value_after_casting = string_to_type(get, typed)
-    
+
     if value_after_casting.nil?
       default
     else

lib/kredis/types/set.rb

@@ -9,12 +9,12 @@ def members
   alias to_a members
 
   def add(*members)
-    sadd types_to_strings(members) if members.flatten.any?
+    sadd types_to_strings(members, typed) if members.flatten.any?
   end
   alias << add
 
   def remove(*members)
-    srem types_to_strings(members) if members.flatten.any?
+    srem types_to_strings(members, typed) if members.flatten.any?
   end
 
   def replace(*members)
@@ -25,7 +25,7 @@ def replace(*members)
   end
 
   def include?(member)
-    sismember type_to_string(member)
+    sismember type_to_string(member, typed)
   end
 
   def size

test/attributes_test.rb

@@ -14,6 +14,7 @@ class Person
   kredis_integer :age
   kredis_decimal :salary
   kredis_datetime :last_seen_at
+  kredis_float :height
   kredis_enum :morning, values: %w[ bright blue black ], default: "bright"
   kredis_slot :attention
   kredis_slots :meetings, available: 3
@@ -103,7 +104,13 @@ class AttributesTest < ActiveSupport::TestCase
   test "decimal" do
     @person.salary.value = 10000.07
     assert_equal 10000.07, @person.salary.value
-    assert_equal "10000.07", @person.salary.to_s
+    assert_equal "0.1000007e5", @person.salary.to_s
+  end
+
+  test "float" do
+    @person.height.value = 1.85
+    assert_equal 1.85, @person.height.value
+    assert_equal "1.85", @person.height.to_s
   end
 
   test "datetime" do