Add delivery failure handling to FASP jobs (#35723)

spec/support/examples/workers/fasp/delivery_failure.rb

@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+RSpec.shared_examples 'worker handling fasp delivery failures' do
+  context 'when provider is not available' do
+    before do
+      provider.update(delivery_last_failed_at: 1.minute.ago)
+      domain = Addressable::URI.parse(provider.base_url).normalized_host
+      UnavailableDomain.create!(domain:)
+    end
+
+    it 'does not attempt connecting and does not fail the job' do
+      expect { subject }.to_not raise_error
+      expect(stubbed_request).to_not have_been_made
+    end
+  end
+
+  context 'when connection to provider fails' do
+    before do
+      base_stubbed_request
+        .to_raise(HTTP::ConnectionError)
+    end
+
+    context 'when provider becomes unavailable' do
+      before do
+        travel_to 5.minutes.ago
+        4.times do
+          provider.delivery_failure_tracker.track_failure!
+          travel_to 1.minute.since
+        end
+      end
+
+      it 'updates the provider and does not fail the job, so it will not be retried' do
+        expect { subject }.to_not raise_error
+        expect(provider.reload.delivery_last_failed_at).to eq Time.current
+      end
+    end
+
+    context 'when provider is still marked as available' do
+      it 'fails the job so it can be retried' do
+        expect { subject }.to raise_error(HTTP::ConnectionError)
+      end
+    end
+  end
+
+  context 'when connection to a previously unavailable provider succeeds' do
+    before do
+      provider.update(delivery_last_failed_at: 2.hours.ago)
+      domain = Addressable::URI.parse(provider.base_url).normalized_host
+      UnavailableDomain.create!(domain:)
+    end
+
+    it 'marks the provider as being available again' do
+      expect { subject }.to_not raise_error
+      expect(provider).to be_available
+    end
+  end
+end