Improve documentation on custom serializers

1 files changed, 21 insertions, 22 deletions

diff --git a/guides/source/active_job_basics.md b/guides/source/active_job_basics.md
index eea64f9367..0ee522e23d 100644
--- a/guides/source/active_job_basics.md
+++ b/guides/source/active_job_basics.md
@@ -345,6 +345,12 @@ Supported types for arguments
 ActiveJob supports the following types of arguments by default:
 
   - Basic types (`NilClass`, `String`, `Integer`, `Fixnum`, `Bignum`, `Float`, `BigDecimal`, `TrueClass`, `FalseClass`)
+  - `Symbol
+  - `ActiveSupport::Duration`
+  - `Date`
+  - `Time`
+  - `DateTime`
+  - `ActiveSupport::TimeWithZone`
   - `Hash`. Keys should be of `String` or `Symbol` type
   - `ActiveSupport::HashWithIndifferentAccess`
   - `Array`
@@ -382,38 +388,31 @@ by default has been mixed into Active Record classes.
 You can extend list of supported types for arguments. You just need to define your own serializer.
 
 ```ruby
-class MySpecialSerializer
-  class << self
-    # Check if this object should be serialized using this serializer
+class MoneySerializer < ActiveJob::Serializers::ObjectSerializer
+    # Check if this object should be serialized using this serializer.
     def serialize?(argument)
-      argument.is_a? MySpecialValueObject
+      argument.is_a? Money
     end
 
     # Convert an object to a simpler representative using supported object types.
-    # The recommended representative is a Hash with a specific key. Keys can be of basic types only
+    # The recommended representative is a Hash with a specific key. Keys can be of basic types only.
+    # You should call `super` to add the custom serializer type to the hash
     def serialize(object)
-      {
-        key => ActiveJob::Serializers.serialize(object.value)
-        'another_attribute' => ActiveJob::Serializers.serialize(object.another_attribute)
-      }
+      super(
+        "cents" => object.cents,
+        "currency" => object.currency
+      )
     end
 
-    # Check if this serialized value be deserialized using this serializer
+    # Check if this serialized value be deserialized using this serializer.
+    # ActiveJob::Serializers::ObjectSerializer#deserialize? already take care of this.
     def deserialize?(argument)
-      argument.is_a?(Hash) && argument.keys == [key, 'another_attribute']
+      super
     end
 
     # Convert serialized value into a proper object
-    def deserialize(object)
-      value = ActiveJob::Serializers.deserialize(object[key])
-      another_attribute = ActiveJob::Serializers.deserialize(object['another_attribute'])
-      MySpecialValueObject.new value, another_attribute
-    end
-
-    # Define this method if you are using a hash as a representative.
-    # This key will be added to a list of restricted keys for hashes. Use basic types only
-    def key
-      "_aj_custom_dummy_value_object"
+    def deserialize(hash)
+      Money.new hash["cents"], hash["currency"]
     end
   end
 end
@@ -422,7 +421,7 @@ end
 And now you just need to add this serializer to a list:
 
 ```ruby
-ActiveJob::Base.add_serializers(MySpecialSerializer)
+Rails.application.config.active_job.custom_serializers << MySpecialSerializer
 ```