Send notification on 3 push failures

app/models/notification/push_subscription_error.rb

@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class Notification::PushSubscriptionError < Notification
+end

app/views/notifications/type/_webpushsubscription.html.haml

@@ -0,0 +1,10 @@
+.media.notification
+  .notification__icon
+    %span.fa-stack
+      %i.fa.fa-2x.fa-fw.fa-bell
+      %i.fa.fa-stack-1x.fa-fw.fa-exclamation-triangle.text-danger.pl-2
+  .media-body
+    %h6.media-heading.notification__user
+      = t(".heading")
+    .notification__text
+      = t(".text_html", settings_push: link_to(t(".settings_push"), settings_push_notifications_path))

config/initializers/rpush.rb

@@ -63,6 +63,14 @@ Rpush.reflect do |on|
       subscription = WebPushSubscription::where("subscription ->> 'endpoint' = ?", notification.registration_ids.first[:endpoint])
       subscription.increment :failures
       subscription.save
+
+      if subscription.failures > 3
+        Notification::PushSubscriptionError.create(
+          target:      subscription,
+          recipient:   subscription.user,
+          new:         true
+        )
+      end
     end
   end
 

config/locales/views.en.yml

@@ -354,6 +354,10 @@ en:
           link_text: "your comment"
       follow:
         heading_html: "followed you %{time} ago"
+      webpushsubscription:
+        heading: "Push notifications are failing to send to one of your devices."
+        text_html: "Please check the %{settings_push} if you still want to be notified."
+        settings_push: "push notification settings"
       expiredtwitterserviceconnection:
         heading: "Twitter connection expired"
         text_html: "If you would like to continue automatically sharing your answers to Twitter, head to %{settings_sharing} and re-connect your account."