Fixes #3145 - EmailParser (process_unprocessable_mail) ignores group routings.

app/models/channel/email_parser.rb

@@ -226,6 +226,11 @@ returns
         group = nil
         if channel[:group_id]
           group = Group.lookup(id: channel[:group_id])
+        else
+          mail_to_group = self.class.mail_to_group(mail[:to])
+          if mail_to_group.present?
+            group = mail_to_group
+          end
         end
         if group.blank? || group.active == false
           group = Group.where(active: true).order(id: :asc).first
@@ -322,6 +327,20 @@ returns
     [ticket, article, session_user, mail]
   end
 
+  def self.mail_to_group(to)
+    begin
+      to = Mail::AddressList.new(to)&.addresses&.first&.address
+    rescue
+      Rails.logger.error 'Can not parse :to field for group destination!'
+    end
+    return if to.blank?
+
+    email = EmailAddress.find_by(email: to)
+    return if email&.channel.blank?
+
+    email.channel&.group
+  end
+
   def self.check_attributes_by_x_headers(header_name, value)
     class_name = nil
     attribute = nil

spec/models/channel/email_parser_spec.rb

@@ -124,6 +124,21 @@ RSpec.describe Channel::EmailParser, type: :model do
           expect(Ticket.last.state.name).to eq('new')
         end
 
+        context 'when no channel is given but a group with the :to address exists' do
+          let!(:email_address) { create(:email_address, email: 'baz@qux.net', channel: nil) }
+          let!(:group) { create(:group, name: 'baz headquarter', email_address: email_address) }
+          let!(:channel) do
+            channel = create(:email_channel, group: group)
+            email_address.update(channel: channel)
+            channel
+          end
+
+          it 'sets the group based on the :to field' do
+            described_class.new.process({}, raw_mail)
+            expect(Ticket.last.group.id).to eq(group.id)
+          end
+        end
+
         context 'when from address matches an existing agent' do
           let!(:agent) { create(:agent, email: 'foo@bar.com') }