Handles unsubscribe from notifications via email

- allows unsubscription processing of email in format "reply+%{key}+unsubscribe@acme.com" (example)
- if config.address includes %{key} and replies are enabled every unsubscriable message will include mailto: link in its List-Unsubscribe header

1 files changed, 54 insertions, 0 deletions

diff --git a/lib/gitlab/email/handler/reply_processing.rb b/lib/gitlab/email/handler/reply_processing.rb
new file mode 100644
index 00000000000..32c5caf93e8
--- /dev/null
+++ b/lib/gitlab/email/handler/reply_processing.rb
@@ -0,0 +1,54 @@
+module Gitlab
+  module Email
+    module Handler
+      module ReplyProcessing
+        private
+
+        def author
+          raise NotImplementedError
+        end
+
+        def project
+          raise NotImplementedError
+        end
+
+        def message
+          @message ||= process_message
+        end
+
+        def process_message
+          message = ReplyParser.new(mail).execute.strip
+          add_attachments(message)
+        end
+
+        def add_attachments(reply)
+          attachments = Email::AttachmentUploader.new(mail).execute(project)
+
+          reply + attachments.map do |link|
+            "\n\n#{link[:markdown]}"
+          end.join
+        end
+
+        def validate_permission!(permission)
+          raise UserNotFoundError unless author
+          raise UserBlockedError if author.blocked?
+          raise ProjectNotFound unless author.can?(:read_project, project)
+          raise UserNotAuthorizedError unless author.can?(permission, project)
+        end
+
+        def verify_record!(record:, invalid_exception:, record_name:)
+          return if record.persisted?
+          return if record.errors.key?(:commands_only)
+
+          error_title = "The #{record_name} could not be created for the following reasons:"
+
+          msg = error_title + record.errors.full_messages.map do |error|
+            "\n\n- #{error}"
+          end.join
+
+          raise invalid_exception, msg
+        end
+      end
+    end
+  end
+end