Use delivery's batch_begin_at in SendSubmissionBatchJob

Rather than get the date off a submission, use the batch_begin_at from
the delivery. This makes it easier to re-use the job for sending
weekly batches.

Author: stephencdaly

app/jobs/send_submission_batch_job.rb

@@ -17,7 +17,8 @@ def perform(delivery:)
     latest_submission = submissions.order(created_at: :desc).first
     form = latest_submission.form
     mode = latest_submission.mode_object
-    date = latest_submission.submission_time.to_date
+
+    batch_begin_date = delivery.batch_begin_at.in_time_zone(TimeZoneUtils.submission_time_zone).to_date
 
     set_submission_batch_logging_attributes(form:, mode:, delivery:)
 
@@ -30,7 +31,7 @@ def perform(delivery:)
       end
     end
 
-    message_id = AwsSesSubmissionBatchService.new(submissions_query: submissions, form:, date:, mode:).send_batch
+    message_id = AwsSesSubmissionBatchService.new(submissions_query: submissions, form:, date: batch_begin_date, mode:).send_batch
 
     delivery.new_attempt!
     delivery.update!(
@@ -40,14 +41,14 @@ def perform(delivery:)
     CurrentJobLoggingAttributes.delivery_reference = delivery.delivery_reference
     EventLogger.log_form_event("daily_batch_email_sent", {
       mode: mode.to_s,
-      batch_date: date,
+      batch_date: batch_begin_date,
       number_of_submissions: submissions.count,
     })
 
     submissions.each do |submission|
       EventLogger.log_form_event("included_in_daily_batch_email", {
         submission_reference: submission.reference,
-        batch_date: date,
+        batch_date: batch_begin_date,
       })
     end
   end

spec/jobs/send_submission_batch_job_spec.rb

@@ -5,8 +5,9 @@
   include ActiveJob::TestHelper
 
   let(:mode_string) { "form" }
-  let(:date) { Date.new(2022, 12, 14) }
-  let(:delivery) { create(:delivery, delivery_schedule: "daily", submissions:) }
+  let(:date) { Date.new(2025, 4, 10) }
+  let(:batch_begin_at) { Time.utc(2025, 4, 9, 23, 0, 0) }
+  let(:delivery) { create(:delivery, delivery_schedule: "daily", submissions:, batch_begin_at:) }
 
   let(:form_document) { create(:v2_form_document, :with_steps, name: "My Form", submission_email:) }
   let(:submission_email) { "to@example.com" }
@@ -73,13 +74,25 @@
         expect(mail.to).to include(form_document.submission_email)
       end
 
+      it "includes the date in London time in the subject" do
+        expect(mail.subject).to include("10 April 2025")
+      end
+
       it "updates the delivery" do
         expect(delivery.reload.delivery_reference).to eq(mail.message_id)
         expect(delivery.reload.last_attempt_at).to be_within(1.second).of(@job_ran_at)
       end
 
       context "when the delivery has already been attempted" do
-        let(:delivery) { create(:delivery, delivery_schedule: "daily", submissions:, delivered_at: Time.zone.now - 2.hours, failed_at: Time.zone.now - 1.hour, failure_reason: "bounced") }
+        let(:delivery) do
+          create(:delivery,
+                 delivery_schedule: "daily",
+                 submissions:,
+                 batch_begin_at:,
+                 delivered_at: Time.zone.now - 2.hours,
+                 failed_at: Time.zone.now - 1.hour,
+                 failure_reason: "bounced")
+        end
 
         it "updates the resets the delivery details" do
           expect(delivery.reload.delivered_at).to be_nil
@@ -92,7 +105,7 @@
         expect(mail.attachments).not_to be_empty
 
         filenames = mail.attachments.map(&:filename)
-        expect(filenames).to contain_exactly("govuk_forms_my_form_2022-12-14.csv")
+        expect(filenames).to contain_exactly("govuk_forms_my_form_2025-04-10.csv")
       end
 
       it "attaches a csv containing header plus one line per submission" do