Introduce base NotifyMailer to to abstract away shared Notify mail functionality

app/jobs/email_csv_job.rb

@@ -3,6 +3,8 @@ class EmailCsvJob < ApplicationJob
 
   BYTE_ORDER_MARK = "\uFEFF".freeze # Required to ensure Excel always reads CSV as UTF-8
 
+  EXPIRATION_TIME = 3.hours.to_i
+
   def perform(user, search_term = nil, filters = {}, all_orgs = false, organisation = nil) # rubocop:disable Style/OptionalBooleanParameter
     unfiltered_logs = organisation.present? && user.support? ? LettingsLog.all.where(owning_organisation_id: organisation.id) : user.lettings_logs
     filtered_logs = FilterService.filter_lettings_logs(unfiltered_logs, search_term, filters, all_orgs, user)
@@ -12,8 +14,7 @@ class EmailCsvJob < ApplicationJob
     storage_service = Storage::S3Service.new(Configuration::PaasConfigurationService.new, ENV["CSV_DOWNLOAD_PAAS_INSTANCE"])
     storage_service.write_file(filename, BYTE_ORDER_MARK + filtered_logs.to_csv(user))
 
-    duration = 3.hours.to_i
-    url = storage_service.get_presigned_url(filename, duration)
+    url = storage_service.get_presigned_url(filename, EXPIRATION_TIME)
 
     CsvDownloadMailer.new.send_email(user, url, duration)
   end

app/mailers/csv_download_mailer.rb

@@ -1,30 +1,11 @@
-class CsvDownloadMailer
-  require "notifications/client"
-
+class CsvDownloadMailer < NotifyMailer
   CSV_DOWNLOAD_TEMPLATE_ID = "7890e3b9-8c0d-4d08-bafe-427fd7cd95bf".freeze
 
-  def notify_client
-    @notify_client ||= ::Notifications::Client.new(ENV["GOVUK_NOTIFY_API_KEY"])
-  end
-
-  def send_email(user, link, duration)
-    return true if intercept_send?(user.email)
-
-    notify_client.send_email(
+  def send_csv_download_mail(user, link, duration)
+    send_email(
       email_address: user.email,
       template_id: CSV_DOWNLOAD_TEMPLATE_ID,
-      personalisation: { name: user.name || user.email, link:, duration: ActiveSupport::Duration.build(duration).inspect },
+      personalisation: { name: user.name, link:, duration: ActiveSupport::Duration.build(duration).inspect },
     )
   end
-
-  def intercept_send?(email)
-    return false unless email_allowlist
-
-    email_domain = email.split("@").last.downcase
-    !(Rails.env.production? || Rails.env.test?) && email_allowlist.exclude?(email_domain)
-  end
-
-  def email_allowlist
-    Rails.application.credentials[:email_allowlist]
-  end
 end

app/mailers/notify_mailer.rb

@@ -0,0 +1,37 @@
+class NotifyMailer
+  require "notifications/client"
+
+  def notify_client
+    @notify_client ||= ::Notifications::Client.new(ENV["GOVUK_NOTIFY_API_KEY"])
+  end
+
+  def send_email(email, template_id, personalisation)
+    return true if intercept_send?(email)
+
+    notify_client.send_email(
+      email_address: email,
+      template_id:,
+      personalisation:,
+    )
+  end
+
+  def personalisation(record, token, url, username: false)
+    {
+      name: record.name || record.email,
+      email: username || record.email,
+      organisation: record.respond_to?(:organisation) ? record.organisation.name : "",
+      link: "#{url}#{token}",
+    }
+  end
+
+  def intercept_send?(email)
+    return false unless email_allowlist
+
+    email_domain = email.split("@").last.downcase
+    !(Rails.env.production? || Rails.env.test?) && email_allowlist.exclude?(email_domain)
+  end
+
+  def email_allowlist
+    Rails.application.credentials[:email_allowlist]
+  end
+end