Adds metadata to outboxes

lib/outboxable.rb

@@ -27,7 +27,12 @@ module Outboxable
       outboxes.new(
         routing_key:,
         exchange: Outboxable.configuration.rabbitmq_exchange_name,
-        payload: as_json
+        payload: as_json,
+        metadata: if respond_to?(:metadata_for_outbox)
+                metadata_for_outbox
+              else
+                {}
+              end
       )
     end
 

lib/templates/create_outboxable_outboxes.rb

@@ -15,6 +15,7 @@ class CreateOutboxableOutboxes < ActiveRecord::Migration[7.0]
 
       t.jsonb :payload, default: {}
       t.jsonb :headers, default: {}
+      t.jsonb :metadata, default: {}, null: true
 
       t.integer :size, null: false, default: 0
 

lib/templates/mongoid_outbox.rb

@@ -22,6 +22,7 @@ class Outbox
 
   field :payload, type: Hash, default: {}
   field :headers, type: Hash, default: {}
+  field :metadata, type: Hash, default: {}
 
   index({ idempotency_key: 1 }, { unique: true, name: 'idempotency_key_unique_index' })