amelioration(mail): ajoute d'un simili rate limiter pour envoyer les mails sur des fenetres de temps ayant une limite

app/jobs/cron/expired_dossiers_brouillon_deletion_job.rb

@@ -2,6 +2,6 @@ class Cron::ExpiredDossiersBrouillonDeletionJob < Cron::CronJob
   self.schedule_expression = "every day at 10 pm"
 
   def perform(*args)
-    ExpiredDossiersDeletionService.process_expired_dossiers_brouillon
+    ExpiredDossiersDeletionService.new.process_expired_dossiers_brouillon
   end
 end

app/jobs/cron/expired_dossiers_en_construction_deletion_job.rb

@@ -2,6 +2,6 @@ class Cron::ExpiredDossiersEnConstructionDeletionJob < Cron::CronJob
   self.schedule_expression = "every day at 3 pm"
 
   def perform(*args)
-    ExpiredDossiersDeletionService.process_expired_dossiers_en_construction
+    ExpiredDossiersDeletionService.new.process_expired_dossiers_en_construction
   end
 end

app/jobs/cron/expired_dossiers_termine_deletion_job.rb

@@ -2,6 +2,6 @@ class Cron::ExpiredDossiersTermineDeletionJob < Cron::CronJob
   self.schedule_expression = "every day at 7 am"
 
   def perform(*args)
-    ExpiredDossiersDeletionService.process_expired_dossiers_termine
+    ExpiredDossiersDeletionService.new.process_expired_dossiers_termine
   end
 end

app/services/expired_dossiers_deletion_service.rb

@@ -1,20 +1,28 @@
 class ExpiredDossiersDeletionService
-  def self.process_expired_dossiers_brouillon
+  def initialize(rate_limiter: MailRateLimiter.new(limit: 200, window: 10.minutes))
+    @rate_limiter = rate_limiter
+  end
+
+  def process_expired_dossiers_brouillon
     send_brouillon_expiration_notices
     delete_expired_brouillons_and_notify
   end
 
-  def self.process_expired_dossiers_en_construction
+  def process_expired_dossiers_en_construction
     send_en_construction_expiration_notices
     delete_expired_en_construction_and_notify
   end
 
-  def self.process_expired_dossiers_termine
+  def process_expired_dossiers_termine
     send_termine_expiration_notices
     delete_expired_termine_and_notify
   end
 
-  def self.send_brouillon_expiration_notices
+  def safe_send_email(mail)
+    @rate_limiter.send_with_delay(mail)
+  end
+
+  def send_brouillon_expiration_notices
     dossiers_close_to_expiration = Dossier
       .brouillon_close_to_expiration
       .without_brouillon_expiration_notice_sent
@@ -24,66 +32,70 @@ class ExpiredDossiersDeletionService
     dossiers_close_to_expiration.in_batches.update_all(brouillon_close_to_expiration_notice_sent_at: Time.zone.now)
 
     user_notifications.each do |(email, dossiers)|
-      DossierMailer.notify_brouillon_near_deletion(
+      mail = DossierMailer.notify_brouillon_near_deletion(
         dossiers,
         email
-      ).deliver_later
+      )
+      safe_send_email(mail)
     end
   end
 
-  def self.send_en_construction_expiration_notices
+  def send_en_construction_expiration_notices
     send_expiration_notices(
       Dossier.en_construction_close_to_expiration.without_en_construction_expiration_notice_sent,
       :en_construction_close_to_expiration_notice_sent_at
     )
   end
 
-  def self.send_termine_expiration_notices
+  def send_termine_expiration_notices
     send_expiration_notices(
       Dossier.termine_close_to_expiration.without_termine_expiration_notice_sent,
       :termine_close_to_expiration_notice_sent_at
     )
   end
 
-  def self.delete_expired_brouillons_and_notify
+  def delete_expired_brouillons_and_notify
     user_notifications = group_by_user_email(Dossier.brouillon_expired)
       .map { |(email, dossiers)| [email, dossiers.map(&:hash_for_deletion_mail)] }
 
     Dossier.brouillon_expired.in_batches.destroy_all
 
     user_notifications.each do |(email, dossiers_hash)|
-      DossierMailer.notify_brouillon_deletion(
+      mail = DossierMailer.notify_brouillon_deletion(
         dossiers_hash,
         email
-      ).deliver_later
+      )
+      safe_send_email(mail)
     end
   end
 
-  def self.delete_expired_en_construction_and_notify
+  def delete_expired_en_construction_and_notify
     delete_expired_and_notify(Dossier.en_construction_expired)
   end
 
-  def self.delete_expired_termine_and_notify
+  def delete_expired_termine_and_notify
     delete_expired_and_notify(Dossier.termine_expired, notify_on_closed_procedures_to_user: true)
   end
 
   private
 
-  def self.send_expiration_notices(dossiers_close_to_expiration, close_to_expiration_flag)
+  def send_expiration_notices(dossiers_close_to_expiration, close_to_expiration_flag)
     user_notifications = group_by_user_email(dossiers_close_to_expiration)
     administration_notifications = group_by_fonctionnaire_email(dossiers_close_to_expiration)
 
     dossiers_close_to_expiration.in_batches.update_all(close_to_expiration_flag => Time.zone.now)
 
     user_notifications.each do |(email, dossiers)|
-      DossierMailer.notify_near_deletion_to_user(dossiers, email).deliver_later
+      mail = DossierMailer.notify_near_deletion_to_user(dossiers, email)
+      safe_send_email(mail)
     end
     administration_notifications.each do |(email, dossiers)|
-      DossierMailer.notify_near_deletion_to_administration(dossiers, email).deliver_later
+      mail = DossierMailer.notify_near_deletion_to_administration(dossiers, email)
+      safe_send_email(mail)
     end
   end
 
-  def self.delete_expired_and_notify(dossiers_to_remove, notify_on_closed_procedures_to_user: false)
+  def delete_expired_and_notify(dossiers_to_remove, notify_on_closed_procedures_to_user: false)
     user_notifications = group_by_user_email(dossiers_to_remove, notify_on_closed_procedures_to_user: notify_on_closed_procedures_to_user)
       .map { |(email, dossiers)| [email, dossiers.map(&:id)] }
     administration_notifications = group_by_fonctionnaire_email(dossiers_to_remove)
@@ -98,24 +110,26 @@ class ExpiredDossiersDeletionService
     user_notifications.each do |(email, dossier_ids)|
       dossier_ids = dossier_ids.intersection(deleted_dossier_ids)
       if dossier_ids.present?
-        DossierMailer.notify_automatic_deletion_to_user(
+        mail = DossierMailer.notify_automatic_deletion_to_user(
           DeletedDossier.where(dossier_id: dossier_ids).to_a,
           email
-        ).deliver_later
+        )
+        safe_send_email(mail)
       end
     end
     administration_notifications.each do |(email, dossier_ids)|
       dossier_ids = dossier_ids.intersection(deleted_dossier_ids)
       if dossier_ids.present?
-        DossierMailer.notify_automatic_deletion_to_administration(
+        mail = DossierMailer.notify_automatic_deletion_to_administration(
           DeletedDossier.where(dossier_id: dossier_ids).to_a,
           email
-        ).deliver_later
+        )
+        safe_send_email(mail)
       end
     end
   end
 
-  def self.group_by_user_email(dossiers, notify_on_closed_procedures_to_user: false)
+  def group_by_user_email(dossiers, notify_on_closed_procedures_to_user: false)
     dossiers
       .visible_by_user
       .with_notifiable_procedure(notify_on_closed: notify_on_closed_procedures_to_user)
@@ -124,7 +138,7 @@ class ExpiredDossiersDeletionService
       .map { |(user, dossiers)| [user.email, dossiers] }
   end
 
-  def self.group_by_fonctionnaire_email(dossiers)
+  def group_by_fonctionnaire_email(dossiers)
     dossiers
       .visible_by_administration
       .with_notifiable_procedure(notify_on_closed: true)

app/services/mail_rate_limiter.rb

@@ -0,0 +1,32 @@
+class MailRateLimiter
+  attr_reader :delay, :current_window
+
+  def send_with_delay(mail)
+    if current_window_full?
+      @delay += @window
+    end
+    if current_window_full? || current_window_expired?
+      @current_window = { started_at: Time.current, sent: 0 }
+    end
+    @current_window[:sent] += 1
+
+    mail.deliver_later(wait: delay)
+  end
+
+  private
+
+  def initialize(limit:, window:)
+    @limit = limit
+    @window = window
+    @current_window = { started_at: Time.current, sent: 0 }
+    @delay = 0
+  end
+
+  def current_window_expired?
+    @current_window[:started_at] + @window <= Time.zone.now.utc
+  end
+
+  def current_window_full?
+    @current_window[:sent] == @limit
+  end
+end

spec/lib/mail_rate_limiter_spec.rb

@@ -0,0 +1,26 @@
+describe MailRateLimiter do
+  describe 'hits limits' do
+    let(:limit) { 10 }
+    let(:window) { 2.seconds }
+    let(:rate_limiter) { MailRateLimiter.new(limit:, window:) }
+    let(:mail) { DossierMailer.notify_automatic_deletion_to_user([], 'tartampion@france.fr') }
+
+    it 'decreases current_window[:limit]' do
+      expect { rate_limiter.send_with_delay(mail) }.to change { rate_limiter.current_window[:sent] }.by(1)
+    end
+
+    it 'increases the delay by window when it reaches the max number of call' do
+      expect do
+        (limit + 1).times { rate_limiter.send_with_delay(mail) }
+      end.to change { rate_limiter.delay }.by(window)
+    end
+
+    it 'renews current_window when it expires' do
+      rate_limiter.send_with_delay(mail)
+      Timecop.travel(window + 1.second) do
+        rate_limiter.send_with_delay(mail)
+        expect(rate_limiter.current_window[:sent]).to eq(1)
+      end
+    end
+  end
+end

spec/services/expired_dossiers_deletion_service_spec.rb

@@ -6,7 +6,7 @@ describe ExpiredDossiersDeletionService do
   let(:procedure) { create(:procedure, :published, procedure_opts) }
   let(:procedure_2) { create(:procedure, :published, procedure_opts) }
   let(:reference_date) { Date.parse("March 8") }
-
+  let(:service) { ExpiredDossiersDeletionService.new }
   describe '#process_expired_dossiers_brouillon' do
     before { Timecop.freeze(reference_date) }
     after  { Timecop.return }
@@ -26,7 +26,7 @@ describe ExpiredDossiersDeletionService do
         allow(DossierMailer).to receive(:notify_brouillon_near_deletion).and_call_original
         allow(DossierMailer).to receive(:notify_brouillon_deletion).and_call_original
 
-        ExpiredDossiersDeletionService.process_expired_dossiers_brouillon
+        service.process_expired_dossiers_brouillon
       end
 
       it 'emails should be sent' do
@@ -58,7 +58,7 @@ describe ExpiredDossiersDeletionService do
     context 'with a single dossier' do
       let!(:dossier) { create(:dossier, procedure: procedure, created_at: created_at) }
 
-      before { ExpiredDossiersDeletionService.send_brouillon_expiration_notices }
+      before { service.send_brouillon_expiration_notices }
 
       context 'when the dossier is not close to expiration' do
         let(:created_at) { (conservation_par_defaut - 2.weeks - 1.day).ago }
@@ -80,7 +80,7 @@ describe ExpiredDossiersDeletionService do
       let!(:dossier_1) { create(:dossier, procedure: procedure, user: user, created_at: (conservation_par_defaut - 2.weeks + 1.day).ago) }
       let!(:dossier_2) { create(:dossier, procedure: procedure_2, user: user, created_at: (conservation_par_defaut - 2.weeks + 1.day).ago) }
 
-      before { ExpiredDossiersDeletionService.send_brouillon_expiration_notices }
+      before { service.send_brouillon_expiration_notices }
 
       it { expect(DossierMailer).to have_received(:notify_brouillon_near_deletion).once }
       it { expect(DossierMailer).to have_received(:notify_brouillon_near_deletion).with(match_array([dossier_1, dossier_2]), user.email) }
@@ -98,7 +98,7 @@ describe ExpiredDossiersDeletionService do
     context 'with a single dossier' do
       let!(:dossier) { create(:dossier, procedure: procedure, brouillon_close_to_expiration_notice_sent_at: notice_sent_at) }
 
-      before { ExpiredDossiersDeletionService.delete_expired_brouillons_and_notify }
+      before { service.delete_expired_brouillons_and_notify }
 
       context 'when no notice has been sent' do
         let(:notice_sent_at) { nil }
@@ -128,7 +128,7 @@ describe ExpiredDossiersDeletionService do
       let!(:dossier_1) { create(:dossier, procedure: procedure, user: user, brouillon_close_to_expiration_notice_sent_at: (warning_period + 1.day).ago) }
       let!(:dossier_2) { create(:dossier, procedure: procedure_2, user: user, brouillon_close_to_expiration_notice_sent_at: (warning_period + 1.day).ago) }
 
-      before { ExpiredDossiersDeletionService.delete_expired_brouillons_and_notify }
+      before { service.delete_expired_brouillons_and_notify }
 
       it { expect(DossierMailer).to have_received(:notify_brouillon_deletion).once }
       it { expect(DossierMailer).to have_received(:notify_brouillon_deletion).with(match_array([dossier_1.hash_for_deletion_mail, dossier_2.hash_for_deletion_mail]), user.email) }
@@ -147,7 +147,7 @@ describe ExpiredDossiersDeletionService do
     context 'with a single dossier' do
       let!(:dossier) { create(:dossier, :en_construction, :followed, procedure: procedure, en_construction_at: en_construction_at) }
 
-      before { ExpiredDossiersDeletionService.send_en_construction_expiration_notices }
+      before { service.send_en_construction_expiration_notices }
 
       context 'when the dossier is not near deletion' do
         let(:en_construction_at) { (conservation_par_defaut - 2.weeks - 1.day).ago }
@@ -178,7 +178,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         instructeur.followed_dossiers << dossier_1 << dossier_2
-        ExpiredDossiersDeletionService.send_en_construction_expiration_notices
+        service.send_en_construction_expiration_notices
       end
 
       it { expect(DossierMailer).to have_received(:notify_near_deletion_to_user).once }
@@ -195,7 +195,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         administrateur.instructeur.followed_dossiers << dossier
-        ExpiredDossiersDeletionService.send_en_construction_expiration_notices
+        service.send_en_construction_expiration_notices
       end
 
       it { expect(DossierMailer).to have_received(:notify_near_deletion_to_user).once }
@@ -219,7 +219,7 @@ describe ExpiredDossiersDeletionService do
       let!(:dossier) { create(:dossier, :en_construction, :followed, procedure: procedure, en_construction_close_to_expiration_notice_sent_at: notice_sent_at) }
       let(:deleted_dossier) { DeletedDossier.find_by(dossier_id: dossier.id) }
 
-      before { ExpiredDossiersDeletionService.delete_expired_en_construction_and_notify }
+      before { service.delete_expired_en_construction_and_notify }
 
       context 'when no notice has been sent' do
         let(:notice_sent_at) { nil }
@@ -261,7 +261,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         instructeur.followed_dossiers << dossier_1 << dossier_2
-        ExpiredDossiersDeletionService.delete_expired_en_construction_and_notify
+        service.delete_expired_en_construction_and_notify
       end
 
       it { expect(DossierMailer).to have_received(:notify_automatic_deletion_to_user).once }
@@ -290,7 +290,7 @@ describe ExpiredDossiersDeletionService do
     context 'with a single dossier' do
       let!(:dossier) { create(:dossier, :followed, state: :accepte, procedure: procedure, processed_at: processed_at) }
 
-      before { ExpiredDossiersDeletionService.send_termine_expiration_notices }
+      before { service.send_termine_expiration_notices }
 
       context 'when the dossier is not near deletion' do
         let(:processed_at) { (conservation_par_defaut - 2.weeks - 1.day).ago }
@@ -321,7 +321,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         instructeur.followed_dossiers << dossier_1 << dossier_2
-        ExpiredDossiersDeletionService.send_termine_expiration_notices
+        service.send_termine_expiration_notices
       end
 
       it { expect(DossierMailer).to have_received(:notify_near_deletion_to_user).once }
@@ -338,7 +338,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         administrateur.instructeur.followed_dossiers << dossier
-        ExpiredDossiersDeletionService.send_termine_expiration_notices
+        service.send_termine_expiration_notices
       end
 
       it { expect(DossierMailer).to have_received(:notify_near_deletion_to_user).once }
@@ -366,7 +366,7 @@ describe ExpiredDossiersDeletionService do
       let!(:dossier) { create(:dossier, :followed, :accepte, procedure: procedure, termine_close_to_expiration_notice_sent_at: notice_sent_at) }
       let(:deleted_dossier) { DeletedDossier.find_by(dossier_id: dossier.id) }
 
-      before { ExpiredDossiersDeletionService.delete_expired_termine_and_notify }
+      before { service.delete_expired_termine_and_notify }
 
       context 'when no notice has been sent' do
         let(:notice_sent_at) { nil }
@@ -408,7 +408,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         instructeur.followed_dossiers << dossier_1 << dossier_2
-        ExpiredDossiersDeletionService.delete_expired_termine_and_notify
+        service.delete_expired_termine_and_notify
       end
 
       it { expect(DossierMailer).to have_received(:notify_automatic_deletion_to_user).once }
@@ -430,7 +430,7 @@ describe ExpiredDossiersDeletionService do
 
       before do
         instructeur.followed_dossiers << dossier_1 << dossier_2
-        ExpiredDossiersDeletionService.delete_expired_termine_and_notify
+        service.delete_expired_termine_and_notify
       end
 
       it { expect(DossierMailer).to have_received(:notify_automatic_deletion_to_user).once }