DEV: Move array type custom fields to JSON type in automation (#26939)

The automation plugin has 4 custom field types that are array typed. However, array typed custom fields are deprecated and should be migrated to JSON type.

This commit does a couple of things:

1. Migrate all four custom fields to JSON
2. Fix a couple of small bugs that have been discovered while migrating the custom fields to JSON (see the comments on this commit's PR for details https://github.com/discourse/discourse/pull/26939)

plugins/automation/lib/discourse_automation/event_handlers.rb

@@ -75,7 +75,9 @@ module DiscourseAutomation
         .find_each do |automation|
           once_per_user = automation.trigger_field("once_per_user")["value"]
           if once_per_user &&
-               UserCustomField.exists?(name: DiscourseAutomation::CUSTOM_FIELD, user_id: user.id)
+               user.custom_fields[
+                 DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD
+               ].presence&.include?(automation.id)
             next
           end
 
@@ -135,7 +137,8 @@ module DiscourseAutomation
             user.save_custom_fields
           end
 
-          automation.attach_custom_field(user)
+          automation.add_id_to_custom_field(user, DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD)
+
           automation.trigger!("kind" => name, "user" => user, "user_data" => user_data)
         end
     end

plugins/automation/lib/discourse_automation/post_extension.rb

@@ -10,9 +10,9 @@ module DiscourseAutomation
       return if !SiteSetting.discourse_automation_enabled
       return if self.post_type == Post.types[:small_action]
       return if !topic
-      return if topic.custom_fields[DiscourseAutomation::CUSTOM_FIELD].blank?
+      return if topic.custom_fields[DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD].blank?
 
-      topic.custom_fields[DiscourseAutomation::CUSTOM_FIELD].each do |automation_id|
+      topic.custom_fields[DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD].each do |automation_id|
         automation = DiscourseAutomation::Automation.find_by(id: automation_id)
         next if automation&.script != DiscourseAutomation::Scripts::TOPIC_REQUIRED_WORDS
 

plugins/automation/lib/discourse_automation/scripts/auto_responder.rb

@@ -70,9 +70,7 @@ DiscourseAutomation::Scriptable.add(DiscourseAutomation::Scripts::AUTO_RESPONDER
         end
         .join("\n\n")
 
-    value = (Array(post.topic.custom_fields[key]) << automation.id).compact.uniq
-    post.topic.custom_fields[key] = value
-    post.topic.save_custom_fields
+    automation.add_id_to_custom_field(post.topic, key)
 
     PostCreator.create!(
       answering_user,

plugins/automation/lib/discourse_automation/triggers/topic.rb

@@ -12,17 +12,19 @@ DiscourseAutomation::Triggerable.add(DiscourseAutomation::Triggers::TOPIC) do
         previous_topic = Topic.find_by(id: previous_topic_id)
 
         if previous_topic
-          TopicCustomField.where(
-            topic_id: previous_topic_id,
-            name: DiscourseAutomation::CUSTOM_FIELD,
-            value: automation.id,
-          ).delete_all
+          automation.remove_id_from_custom_field(
+            previous_topic,
+            DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD,
+          )
         end
       end
 
       if topic_id
         topic = Topic.find_by(id: topic_id)
-        topic&.upsert_custom_fields(DiscourseAutomation::CUSTOM_FIELD => automation.id)
+
+        next if !topic
+
+        automation.add_id_to_custom_field(topic, DiscourseAutomation::AUTOMATION_IDS_CUSTOM_FIELD)
       end
     end
   end