Cleanup and validate emails on push recipients

app/models/project_services/emails_on_push_service.rb

@@ -3,10 +3,19 @@
 class EmailsOnPushService < Service
   include NotificationBranchSelection
 
+  RECIPIENTS_LIMIT = 750
+
   boolean_accessor :send_from_committer_email
   boolean_accessor :disable_diffs
   prop_accessor :recipients, :branches_to_be_notified
-  validates :recipients, presence: true, if: :valid_recipients?
+  validates :recipients, presence: true, if: :validate_recipients?
+  validate :number_of_recipients_within_limit, if: :validate_recipients?
+
+  def self.valid_recipients(recipients)
+    recipients.split.select do |recipient|
+      recipient.include?('@')
+    end.uniq(&:downcase)
+  end
 
   def title
     s_('EmailsOnPushService|Emails on push')
@@ -67,7 +76,22 @@ class EmailsOnPushService < Service
       { type: 'checkbox', name: 'disable_diffs', title: s_("EmailsOnPushService|Disable code diffs"),
         help: s_("EmailsOnPushService|Don't include possibly sensitive code diffs in notification body.") },
       { type: 'select', name: 'branches_to_be_notified', choices: branch_choices },
-      { type: 'textarea', name: 'recipients', placeholder: s_('EmailsOnPushService|Emails separated by whitespace') }
+      {
+        type: 'textarea',
+        name: 'recipients',
+        placeholder: s_('EmailsOnPushService|tanuki@example.com gitlab@example.com'),
+        help: s_('EmailsOnPushService|Emails separated by whitespace.')
+      }
     ]
   end
+
+  private
+
+  def number_of_recipients_within_limit
+    return if recipients.blank?
+
+    if self.class.valid_recipients(recipients).size > RECIPIENTS_LIMIT
+      errors.add(:recipients, s_("EmailsOnPushService|can't exceed %{recipients_limit}") % { recipients_limit: RECIPIENTS_LIMIT })
+    end
+  end
 end

app/models/project_services/irker_service.rb

@@ -6,7 +6,7 @@ class IrkerService < Service
   prop_accessor :server_host, :server_port, :default_irc_uri
   prop_accessor :recipients, :channels
   boolean_accessor :colorize_messages
-  validates :recipients, presence: true, if: :valid_recipients?
+  validates :recipients, presence: true, if: :validate_recipients?
 
   before_validation :get_channels
 

app/models/project_services/pipelines_email_service.rb

@@ -5,7 +5,7 @@ class PipelinesEmailService < Service
 
   prop_accessor :recipients, :branches_to_be_notified
   boolean_accessor :notify_only_broken_pipelines, :notify_only_default_branch
-  validates :recipients, presence: true, if: :valid_recipients?
+  validates :recipients, presence: true, if: :validate_recipients?
 
   def initialize_properties
     if properties.nil?

app/models/service.rb

@@ -460,7 +460,7 @@ class Service < ApplicationRecord
     errors.add(:project_id, 'The service cannot belong to both a project and a group') if project_id && group_id
   end
 
-  def valid_recipients?
+  def validate_recipients?
     activated? && !importing?
   end
 end

app/workers/emails_on_push_worker.rb

@@ -56,7 +56,7 @@ class EmailsOnPushWorker # rubocop:disable Scalability/IdempotentWorker
       end
     end
 
-    valid_recipients(recipients).each do |recipient|
+    EmailsOnPushService.valid_recipients(recipients).each do |recipient|
       send_email(
         recipient,
         project_id,
@@ -92,10 +92,4 @@ class EmailsOnPushWorker # rubocop:disable Scalability/IdempotentWorker
     email.header[:skip_premailer] = true if skip_premailer
     email.deliver_now
   end
-
-  def valid_recipients(recipients)
-    recipients.split.select do |recipient|
-      recipient.include?('@')
-    end.uniq(&:downcase)
-  end
 end

changelogs/unreleased/268207_validate_number_of_recipients_for_email_on_push_service.yml

+---
+title: Add validation for emails on push recipients
+merge_request: 55550
+author:
+type: changed

locale/gitlab.pot

@@ -11487,7 +11487,7 @@ msgstr ""
 msgid "EmailsOnPushService|Emails on push"
 msgstr ""
 
-msgid "EmailsOnPushService|Emails separated by whitespace"
+msgid "EmailsOnPushService|Emails separated by whitespace."
 msgstr ""
 
 msgid "EmailsOnPushService|Send from committer"
@@ -11496,6 +11496,12 @@ msgstr ""
 msgid "EmailsOnPushService|Send notifications from the committer's email address if the domain is part of the domain GitLab is running on (e.g. %{domains})."
 msgstr ""
 
+msgid "EmailsOnPushService|can't exceed %{recipients_limit}"
+msgstr ""
+
+msgid "EmailsOnPushService|tanuki@example.com gitlab@example.com"
+msgstr ""
+
 msgid "Embed"
 msgstr ""
 

spec/models/project_services/emails_on_push_service_spec.rb

@@ -3,6 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe EmailsOnPushService do
+  let_it_be(:project) { create_default(:project).freeze }
+
   describe 'Validations' do
     context 'when service is active' do
       before do
@@ -19,6 +21,42 @@ RSpec.describe EmailsOnPushService do
 
       it { is_expected.not_to validate_presence_of(:recipients) }
     end
+
+    describe 'validates number of recipients' do
+      before do
+        stub_const("#{described_class}::RECIPIENTS_LIMIT", 2)
+      end
+
+      subject(:service) { described_class.new(project: project, recipients: recipients, active: true) }
+
+      context 'valid number of recipients' do
+        let(:recipients) { 'foo@bar.com duplicate@example.com Duplicate@example.com invalid-email' }
+
+        it 'does not count duplicates and invalid emails' do
+          is_expected.to be_valid
+        end
+      end
+
+      context 'invalid number of recipients' do
+        let(:recipients) { 'foo@bar.com bar@foo.com bob@gitlab.com' }
+
+        it { is_expected.not_to be_valid }
+
+        it 'adds an error message' do
+          service.valid?
+
+          expect(service.errors).to contain_exactly('Recipients can\'t exceed 2')
+        end
+
+        context 'when service is not active' do
+          before do
+            service.active = false
+          end
+
+          it { is_expected.to be_valid }
+        end
+      end
+    end
   end
 
   describe '.new' do
@@ -39,6 +77,14 @@ RSpec.describe EmailsOnPushService do
     end
   end
 
+  describe '.valid_recipients' do
+    let(:recipients) { '<invalid> foobar Valid@recipient.com Dup@lica.te dup@lica.te Dup@Lica.te' }
+
+    it 'removes invalid email addresses and removes duplicates by keeping the original capitalization' do
+      expect(described_class.valid_recipients(recipients)).to contain_exactly('Valid@recipient.com', 'Dup@lica.te')
+    end
+  end
+
   describe '#execute' do
     let(:push_data) { { object_kind: 'push' } }
     let(:project)   { create(:project, :repository) }

spec/support/shared_contexts/services_shared_context.rb

@@ -28,6 +28,8 @@ Service.available_services_names.each do |service|
           hash.merge!(k => 1234)
         elsif service == 'jira' && k == :jira_issue_transition_id
           hash.merge!(k => '1,2,3')
+        elsif service == 'emails_on_push' && k == :recipients
+          hash.merge!(k => 'foo@bar.com')
         else
           hash.merge!(k => "someword")
         end