1 files changed, 58 insertions, 26 deletions

diff --git a/lib/gitlab/email/receiver.rb b/lib/gitlab/email/receiver.rb
index f5e47b43a9a..71db8ab6067 100644
--- a/lib/gitlab/email/receiver.rb
+++ b/lib/gitlab/email/receiver.rb
@@ -6,6 +6,8 @@ require_dependency 'gitlab/email/handler'
 module Gitlab
   module Email
     class Receiver
+      include Gitlab::Utils::StrongMemoize
+
       def initialize(raw)
         @raw = raw
       end
@@ -13,11 +15,7 @@ module Gitlab
       def execute
         raise EmptyEmailError if @raw.blank?
 
-        mail = build_mail
-
-        ignore_auto_reply!(mail)
-
-        handler = find_handler(mail)
+        ignore_auto_reply!
 
         raise UnknownIncomingEmail unless handler
 
@@ -26,13 +24,33 @@ module Gitlab
         end
       end
 
+      def mail_metadata
+        {
+          mail_uid: mail.message_id,
+          from_address: mail.from,
+          to_address: mail.to,
+          mail_key: mail_key,
+          references: Array(mail.references),
+          delivered_to: delivered_to.map(&:value),
+          envelope_to: envelope_to.map(&:value),
+          x_envelope_to: x_envelope_to.map(&:value)
+        }
+      end
+
       private
 
-      def find_handler(mail)
-        mail_key = extract_mail_key(mail)
+      def handler
+        strong_memoize(:handler) { find_handler }
+      end
+
+      def find_handler
         Handler.for(mail, mail_key)
       end
 
+      def mail
+        strong_memoize(:mail) { build_mail }
+      end
+
       def build_mail
         Mail::Message.new(@raw)
       rescue Encoding::UndefinedConversionError,
@@ -40,22 +58,24 @@ module Gitlab
         raise EmailUnparsableError, e
       end
 
-      def extract_mail_key(mail)
-        key_from_to_header(mail) || key_from_additional_headers(mail)
+      def mail_key
+        strong_memoize(:mail_key) do
+          key_from_to_header || key_from_additional_headers
+        end
       end
 
-      def key_from_to_header(mail)
+      def key_from_to_header
         mail.to.find do |address|
           key = Gitlab::IncomingEmail.key_from_address(address)
           break key if key
         end
       end
 
-      def key_from_additional_headers(mail)
-        find_key_from_references(mail) ||
-          find_key_from_delivered_to_header(mail) ||
-          find_key_from_envelope_to_header(mail) ||
-          find_key_from_x_envelope_to_header(mail)
+      def key_from_additional_headers
+        find_key_from_references ||
+          find_key_from_delivered_to_header ||
+          find_key_from_envelope_to_header ||
+          find_key_from_x_envelope_to_header
       end
 
       def ensure_references_array(references)
@@ -71,41 +91,53 @@ module Gitlab
         end
       end
 
-      def find_key_from_references(mail)
+      def find_key_from_references
         ensure_references_array(mail.references).find do |mail_id|
           key = Gitlab::IncomingEmail.key_from_fallback_message_id(mail_id)
           break key if key
         end
       end
 
-      def find_key_from_delivered_to_header(mail)
-        Array(mail[:delivered_to]).find do |header|
+      def delivered_to
+        Array(mail[:delivered_to])
+      end
+
+      def envelope_to
+        Array(mail[:envelope_to])
+      end
+
+      def x_envelope_to
+        Array(mail[:x_envelope_to])
+      end
+
+      def find_key_from_delivered_to_header
+        delivered_to.find do |header|
           key = Gitlab::IncomingEmail.key_from_address(header.value)
           break key if key
         end
       end
 
-      def find_key_from_envelope_to_header(mail)
-        Array(mail[:envelope_to]).find do |header|
+      def find_key_from_envelope_to_header
+        envelope_to.find do |header|
           key = Gitlab::IncomingEmail.key_from_address(header.value)
           break key if key
         end
       end
 
-      def find_key_from_x_envelope_to_header(mail)
-        Array(mail[:x_envelope_to]).find do |header|
+      def find_key_from_x_envelope_to_header
+        x_envelope_to.find do |header|
           key = Gitlab::IncomingEmail.key_from_address(header.value)
           break key if key
         end
       end
 
-      def ignore_auto_reply!(mail)
-        if auto_submitted?(mail) || auto_replied?(mail)
+      def ignore_auto_reply!
+        if auto_submitted? || auto_replied?
           raise AutoGeneratedEmailError
         end
       end
 
-      def auto_submitted?(mail)
+      def auto_submitted?
         # Mail::Header#[] is case-insensitive
         auto_submitted = mail.header['Auto-Submitted']&.value
 
@@ -114,7 +146,7 @@ module Gitlab
         auto_submitted && auto_submitted != 'no'
       end
 
-      def auto_replied?(mail)
+      def auto_replied?
         autoreply = mail.header['X-Autoreply']&.value
 
         autoreply && autoreply == 'yes'