active_storage: refactor concerns

Follow-up of #5953.

Refactor the concerns with two goals:

- Getting closer from the way ActiveStorage adds its own hooks.
  Usually ActiveStorage does this using an `Attachment#after_create`
  hook, which then delegates to the blob to enqueue the job.
- Enqueuing each job only once. By hooking on `Attachment#after_create`,
  we guarantee each job will be added only once.

We then let the jobs themselves check if they are relevant or not, and
retry or discard themselves if necessary.

We also need to update the tests a bit, because Rails'
`perform_enqueued_jobs(&block)` test helper doesn't honor the `retry_on`
clause of jobs. Instead it forwards the exception to the caller – which
makes the test fail.

Instead we use the inline version of `perform_enqueued_jobs()`, without
a block, which properly ignores errors catched by retry_on.

spec/controllers/instructeurs/avis_controller_spec.rb

@@ -98,14 +98,10 @@ describe Instructeurs::AvisController, type: :controller do
       end
 
       context 'with attachment' do
-        include ActiveJob::TestHelper
         let(:file) { fixture_file_upload('spec/fixtures/files/piece_justificative_0.pdf', 'application/pdf') }
 
         before do
-          expect(ClamavService).to receive(:safe_file?).and_return(true)
-          perform_enqueued_jobs do
-            post :update, params: { id: avis_without_answer.id, procedure_id: procedure.id, avis: { answer: 'answer', piece_justificative_file: file } }
-          end
+          post :update, params: { id: avis_without_answer.id, procedure_id: procedure.id, avis: { answer: 'answer', piece_justificative_file: file } }
           avis_without_answer.reload
         end
 
@@ -126,7 +122,6 @@ describe Instructeurs::AvisController, type: :controller do
       subject { post :create_commentaire, params: { id: avis_without_answer.id, procedure_id: procedure.id, commentaire: { body: 'commentaire body', piece_jointe: file } } }
 
       before do
-        allow(ClamavService).to receive(:safe_file?).and_return(scan_result)
         Timecop.freeze(now)
       end
 

spec/features/instructeurs/expert_spec.rb

@@ -25,9 +25,8 @@ feature 'Inviting an expert:' do
       check 'avis_invite_linked_dossiers'
       page.select 'confidentiel', from: 'avis_confidentiel'
 
-      perform_enqueued_jobs do
-        click_on 'Demander un avis'
-      end
+      click_on 'Demander un avis'
+      perform_enqueued_jobs
 
       expect(page).to have_content('Une demande d\'avis a été envoyée')
       expect(page).to have_content('Avis des invités')
@@ -38,7 +37,8 @@ feature 'Inviting an expert:' do
       end
 
       expect(Avis.count).to eq(4)
-      expect(all_emails.size).to eq(2)
+      expect(emails_sent_to('expert1@exemple.fr').size).to eq(1)
+      expect(emails_sent_to('expert2@exemple.fr').size).to eq(1)
 
       invitation_email = open_email('expert2@exemple.fr')
       avis = Avis.find_by(email: 'expert2@exemple.fr', dossier: dossier)

spec/jobs/virus_scanner_job_spec.rb

@@ -1,48 +1,49 @@
-RSpec.describe VirusScannerJob, type: :job do
-  include ActiveJob::TestHelper
-
-  let(:champ) do
-    champ = create(:champ_piece_justificative)
-    champ.piece_justificative_file.attach(io: StringIO.new("toto"), filename: "toto.txt", content_type: "text/plain")
-    champ.save
-    champ
+describe VirusScannerJob, type: :job do
+  let(:blob) do
+    ActiveStorage::Blob.create_and_upload!(io: StringIO.new("toto"), filename: "toto.txt", content_type: "text/plain")
   end
 
   subject do
-    perform_enqueued_jobs do
-      VirusScannerJob.perform_later(champ.piece_justificative_file.blob)
+    VirusScannerJob.perform_now(blob)
+  end
+
+  context "when the blob is not analyzed yet" do
+    it "retries the job later" do
+      expect { subject }.to have_enqueued_job(VirusScannerJob)
     end
   end
 
-  context "when no virus is found" do
-    let(:virus_found?) { true }
-
+  context "when the blob has been analyzed" do
     before do
-      allow(ClamavService).to receive(:safe_file?).and_return(virus_found?)
-      subject
+      blob.analyze
     end
 
-    it { expect(champ.reload.piece_justificative_file.virus_scanner.safe?).to be_truthy }
-  end
+    context "when no virus is found" do
+      before do
+        allow(ClamavService).to receive(:safe_file?).and_return(true)
+        subject
+      end
 
-  context "when a virus is found" do
-    let(:virus_found?) { false }
-
-    before do
-      allow(ClamavService).to receive(:safe_file?).and_return(virus_found?)
-      subject
+      it { expect(blob.virus_scanner.safe?).to be_truthy }
     end
 
-    it { expect(champ.reload.piece_justificative_file.virus_scanner.infected?).to be_truthy }
-  end
+    context "when a virus is found" do
+      before do
+        allow(ClamavService).to receive(:safe_file?).and_return(false)
+        subject
+      end
 
-  context "when the blob has been deleted" do
-    before do
-      Champ.find(champ.id).piece_justificative_file.purge
+      it { expect(blob.virus_scanner.infected?).to be_truthy }
     end
 
-    it "ignores the error" do
-      expect { subject }.not_to raise_error
+    context "when the blob has been deleted" do
+      before do
+        ActiveStorage::Blob.find(blob.id).purge
+      end
+
+      it "ignores the error" do
+        expect { subject }.not_to raise_error
+      end
     end
   end
 end

spec/models/champ_spec.rb

@@ -458,7 +458,8 @@ describe Champ do
         end
 
         it 'marks the file as safe once the scan completes' do
-          perform_enqueued_jobs { subject }
+          subject
+          perform_enqueued_jobs
           expect(champ.reload.piece_justificative_file.virus_scanner.safe?).to be_truthy
         end
       end
@@ -480,13 +481,15 @@ describe Champ do
         champ
       end
 
-      it 'enqueues a watermark job on file attachment' do
+      it 'marks the file as needing watermarking' do
         expect(subject.piece_justificative_file.watermark_pending?).to be_truthy
       end
 
       it 'watermarks the file' do
-        perform_enqueued_jobs { subject }
-        expect(champ.reload.piece_justificative_file.blob.metadata[:watermark]).to be_truthy
+        subject
+        perform_enqueued_jobs
+        expect(champ.reload.piece_justificative_file.watermark_pending?).to be_falsy
+        expect(champ.reload.piece_justificative_file.blob.watermark_done?).to be_truthy
       end
     end
   end

spec/models/dossier_spec.rb

@@ -1386,27 +1386,21 @@ describe Dossier do
     it "clean up titres identite on accepter" do
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_truthy
       expect(champ_titre_identite_vide.piece_justificative_file.attached?).to be_falsey
-      perform_enqueued_jobs do
-        dossier.accepter!(dossier.followers_instructeurs.first, "yolo!")
-      end
+      dossier.accepter!(dossier.followers_instructeurs.first, "yolo!")
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_falsey
     end
 
     it "clean up titres identite on refuser" do
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_truthy
       expect(champ_titre_identite_vide.piece_justificative_file.attached?).to be_falsey
-      perform_enqueued_jobs do
-        dossier.refuser!(dossier.followers_instructeurs.first, "yolo!")
-      end
+      dossier.refuser!(dossier.followers_instructeurs.first, "yolo!")
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_falsey
     end
 
     it "clean up titres identite on classer_sans_suite" do
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_truthy
       expect(champ_titre_identite_vide.piece_justificative_file.attached?).to be_falsey
-      perform_enqueued_jobs do
-        dossier.classer_sans_suite!(dossier.followers_instructeurs.first, "yolo!")
-      end
+      dossier.classer_sans_suite!(dossier.followers_instructeurs.first, "yolo!")
       expect(champ_titre_identite.piece_justificative_file.attached?).to be_falsey
     end
 
@@ -1416,9 +1410,7 @@ describe Dossier do
       it "clean up titres identite on accepter_automatiquement" do
         expect(champ_titre_identite.piece_justificative_file.attached?).to be_truthy
         expect(champ_titre_identite_vide.piece_justificative_file.attached?).to be_falsey
-        perform_enqueued_jobs do
-          dossier.accepter_automatiquement!
-        end
+        dossier.accepter_automatiquement!
         expect(champ_titre_identite.piece_justificative_file.attached?).to be_falsey
       end
     end

spec/services/commentaire_service_spec.rb

@@ -29,15 +29,8 @@ describe CommentaireService do
     context 'when it has a file' do
       let(:file) { fixture_file_upload('spec/fixtures/files/piece_justificative_0.pdf', 'application/pdf') }
 
-      before do
-        expect(ClamavService).to receive(:safe_file?).and_return(true)
-      end
-
-      it 'saves the attached file' do
-        perform_enqueued_jobs do
-          commentaire.save
-          expect(commentaire.piece_jointe.attached?).to be_truthy
-        end
+      it 'attaches the file' do
+        expect(commentaire.piece_jointe.attached?).to be_truthy
       end
     end
   end