FEATURE: add reviewable score updated webhook (#12846)

Adds a webhook to notify when a reviewable score is updated.

This is different from created or status changed as additional flags can
roll in and update the score without updating status. Useful for applications
looking to integrate in with Discourse's scores

app/models/reviewable.rb

@@ -213,6 +213,8 @@ class Reviewable < ActiveRecord::Base
     update(score: self.score + rs.score, latest_score: rs.created_at, force_review: force_review)
     topic.update(reviewable_score: topic.reviewable_score + rs.score) if topic
 
+    DiscourseEvent.trigger(:reviewable_score_updated, self)
+
     rs
   end
 
@@ -625,6 +627,10 @@ protected
     )
 
     self.score = result[0].score
+
+    DiscourseEvent.trigger(:reviewable_score_updated, self)
+
+    self.score
   end
 
   def increment_version!(version = nil)

config/initializers/012-web_hook_events.rb

@@ -85,8 +85,13 @@ end
   end
 end
 
-DiscourseEvent.on(:reviewable_created) do |reviewable|
-  WebHook.enqueue_object_hooks(:reviewable, reviewable, :reviewable_created, reviewable.serializer)
+%i(
+  reviewable_created
+  reviewable_score_updated
+).each do |event|
+  DiscourseEvent.on(event) do |reviewable|
+    WebHook.enqueue_object_hooks(:reviewable, reviewable, event, reviewable.serializer)
+  end
 end
 
 DiscourseEvent.on(:reviewable_transitioned_to) do |status, reviewable|

spec/models/web_hook_spec.rb

@@ -494,6 +494,17 @@ describe WebHook do
       payload = JSON.parse(job_args["payload"])
       expect(payload["id"]).to eq(reviewable.id)
 
+      reviewable.add_score(
+        Discourse.system_user,
+        ReviewableScore.types[:off_topic],
+        reason: "test"
+      )
+      job_args = Jobs::EmitWebHookEvent.jobs.last["args"].first
+
+      expect(job_args["event_name"]).to eq("reviewable_score_updated")
+      payload = JSON.parse(job_args["payload"])
+      expect(payload["id"]).to eq(reviewable.id)
+
       reviewable.perform(Discourse.system_user, :reject_user_delete)
       job_args = Jobs::EmitWebHookEvent.jobs.last["args"].first