feat: new background work process

This removes all previous dependencies on RabbitMQ and the need to run separate cron and requeueing processes.

app/models/webhook_request.rb

@@ -5,21 +5,28 @@
 # Table name: webhook_requests
 #
 #  id          :integer          not null, primary key
+#  attempts    :integer          default(0)
+#  error       :text(65535)
+#  event       :string(255)
+#  locked_at   :datetime
+#  locked_by   :string(255)
+#  payload     :text(65535)
+#  retry_after :datetime
+#  url         :string(255)
+#  uuid        :string(255)
+#  created_at  :datetime
 #  server_id   :integer
 #  webhook_id  :integer
-#  url         :string(255)
-#  event       :string(255)
-#  uuid        :string(255)
-#  payload     :text(65535)
-#  attempts    :integer          default(0)
-#  retry_after :datetime
-#  error       :text(65535)
-#  created_at  :datetime
+#
+# Indexes
+#
+#  index_webhook_requests_on_locked_by  (locked_by)
 #
 
 class WebhookRequest < ApplicationRecord
 
   include HasUUID
+  include HasLocking
 
   RETRIES = { 1 => 2.minutes, 2 => 3.minutes, 3 => 6.minutes, 4 => 10.minutes, 5 => 15.minutes }.freeze
 
@@ -31,30 +38,9 @@ class WebhookRequest < ApplicationRecord
 
   serialize :payload, Hash
 
-  after_commit :queue, on: :create
-
-  def self.trigger(server, event, payload = {})
-    unless server.is_a?(Server)
-      server = Server.find(server.to_i)
-    end
-
-    webhooks = server.webhooks.enabled.includes(:webhook_events).references(:webhook_events).where("webhooks.all_events = ? OR webhook_events.event = ?", true, event)
-    webhooks.each do |webhook|
-      server.webhook_requests.create!(event: event, payload: payload, webhook: webhook, url: webhook.url)
-    end
-  end
-
-  def self.requeue_all
-    where("retry_after < ?", Time.now).find_each(&:queue)
-  end
-
-  def queue
-    WebhookDeliveryJob.queue(:main, id: id)
-  end
-
   def deliver
     payload = { event: event, timestamp: created_at.to_f, payload: self.payload, uuid: uuid }.to_json
-    Postal.logger.tagged(event: event, url: url, component: "webhooks") do
+    Postal.logger.tagged(event: event, url: url) do
       Postal.logger.info "Sending webhook request"
       result = Postal::HTTP.post(url, sign: true, json: payload, timeout: 5)
       self.attempts += 1
@@ -74,7 +60,7 @@ class WebhookRequest < ApplicationRecord
 
       if result[:code] >= 200 && result[:code] < 300
         Postal.logger.info "Received #{result[:code]} status code. That's OK."
-        destroy
+        destroy!
         webhook&.update_column(:last_used_at, Time.now)
         true
       else
@@ -82,14 +68,31 @@ class WebhookRequest < ApplicationRecord
         self.error = "Couldn't send to URL. Code received was #{result[:code]}"
         if retry_after
           Postal.logger.info "Will retry #{retry_after} (this was attempt #{self.attempts})"
-          save
+          self.locked_by = nil
+          self.locked_at = nil
+          save!
         else
           Postal.logger.info "Have tried #{self.attempts} times. Giving up."
-          destroy
+          destroy!
         end
         false
       end
     end
   end
 
+  class << self
+
+    def trigger(server, event, payload = {})
+      unless server.is_a?(Server)
+        server = Server.find(server.to_i)
+      end
+
+      webhooks = server.webhooks.enabled.includes(:webhook_events).references(:webhook_events).where("webhooks.all_events = ? OR webhook_events.event = ?", true, event)
+      webhooks.each do |webhook|
+        server.webhook_requests.create!(event: event, payload: payload, webhook: webhook, url: webhook.url)
+      end
+    end
+
+  end
+
 end