Allow for default values

app/models/account.rb

@@ -2,5 +2,5 @@ class Account < ApplicationRecord
   include Joinable
 
   has_one_attached :logo
-  has_settings restrict_room_creation_to_administrators: :boolean, max_invites: 10, name: "hero"
+  has_settings restrict_room_creation_to_administrators: false
 end

lib/rails_ext/active_record_has_json.rb

@@ -1,23 +1,24 @@
 module ActiveRecord
-  class TypedJson
+  class SchematizedJson
     def initialize(schema, data:)
       @schema, @data = schema, data
+      update_data_with_schema_defaults
     end
 
     def assign_data_with_type_casting(new_data)
-      new_data.each { |key, value| send("#{key}=", value) }
+      new_data.each { |key, value| send "#{key}=", value }
     end
 
     private
       def method_missing(method_name, *args, **kwargs)
         key = method_name.to_s.remove(/(\?|=)/)
 
-        if key_type = @schema[key.to_sym]
+        if @schema.key? key.to_sym
           if method_name.ends_with?("?")
             @data[key].present?
           elsif method_name.ends_with?("=")
             value = args.first
-            @data[key] = ActiveModel::Type.lookup(key_type).cast(value)
+            @data[key] = lookup_schema_type_for(key).cast(value)
           else
             @data[key]
           end
@@ -29,13 +30,34 @@ module ActiveRecord
       def respond_to_missing?(method_name, include_private = false)
         @schema.key?(method_name.to_s.remove(/[?=]/).to_sym) || super
       end
+
+      def lookup_schema_type_for(key)
+        type_or_default_value = @schema[key.to_sym]
+
+        case type_or_default_value
+        when :boolean, :integer, :string
+          ActiveModel::Type.lookup(type_or_default_value)
+        when TrueClass, FalseClass
+          ActiveModel::Type.lookup(:boolean)
+        when Integer
+          ActiveModel::Type.lookup(:integer)
+        when String
+          ActiveModel::Type.lookup(:string)
+        else
+          raise "Only boolean, integer, or strings are allowed as JSON schema types"
+        end
+      end
+
+      def update_data_with_schema_defaults
+        @data.reverse_merge!(@schema.to_h { |k, v| [ k.to_s, v.is_a?(Symbol) ? nil : v ] })
+      end
   end
 
   class Base
     class << self
       def has_json(delegate: false, **schemas)
         schemas.each do |name, schema|
-          define_method(name)       { ActiveRecord::TypedJson.new(schema, data: self[name]) }
+          define_method(name)       { ActiveRecord::SchematizedJson.new(schema, data: self[name]) }
           define_method("#{name}=") { |data| send(name).assign_data_with_type_casting(data) }
 
           schema.keys.each do |schema_key|
@@ -43,6 +65,9 @@ module ActiveRecord
             define_method("#{schema_key}?") { send(name).send("#{schema_key}?") }
             define_method("#{schema_key}=") { |value| send(name).send("#{schema_key}=", value) }
           end if delegate
+
+          # Ensures default values are set before saving
+          before_save -> { send(name) }
         end
       end
 

test/models/account_test.rb

@@ -15,4 +15,9 @@ class AccountTest < ActiveSupport::TestCase
     accounts(:signal).update!(settings: { "restrict_room_creation_to_administrators" => "false" })
     assert_not accounts(:signal).reload.restrict_room_creation_to_administrators?
   end
+
+  test "default settings" do
+    a = Account.create! name: "New account"
+    assert_equal({ "restrict_room_creation_to_administrators" => false }, a[:settings])
+  end
 end