FIX: Division by zero error on WebHookEventsDailyAggregate (#27667)

* FIX: Division by zero error on WebHookEventsDailyAggregate

* DEV: Update implementation of WebHookEventsDailyAggregate to handle division by zero error

app/models/web_hook_events_daily_aggregate.rb

@@ -25,8 +25,14 @@ class WebHookEventsDailyAggregate < ActiveRecord::Base
         self.web_hook_id,
       )
 
-    self.mean_duration = events.sum(:duration) / events.count
+    if events.empty?
+      self.mean_duration = 0
+      self.successful_event_count = 0
+      self.failed_event_count = 0
+      return
+    end
 
+    self.mean_duration = events.sum(:duration) / events.count
     self.successful_event_count = events.where("status >= 200 AND status <= 299").count
     self.failed_event_count = events.where("status < 200 OR status > 299").count
   end

spec/models/web_hook_events_daily_aggregate_spec.rb

@@ -110,5 +110,11 @@ RSpec.describe WebHookEventsDailyAggregate do
         WebHookEventsDailyAggregate.count
       }
     end
+
+    it "should not fail if there are no events" do
+      expect { Jobs::AggregateWebHooksEvents.new.execute(date: 99.days.ago) }.not_to raise_error
+
+      expect(WebHookEventsDailyAggregate.count).to eq(1)
+    end
   end
 end