Prevent double-vaccination by navigating back (#2737)

When using the vaccinate flow it's possible to inadvertently record two
vaccinations for the same patient by navigating back to the confirmation
after submitting it and then submitting it again. Instead, once
recorded, we associate the draft vaccination record with the saved one
so this changes to the edit vaccination record flow.

app/controllers/draft_vaccination_records_controller.rb

@@ -97,6 +97,10 @@ def handle_confirm
 
     send_vaccination_confirmation(@vaccination_record) if should_notify_parents
 
+    # In case the user navigates back to try and edit the newly created
+    # vaccination record.
+    @draft_vaccination_record.update!(editing_id: @vaccination_record.id)
+
     heading =
       if @vaccination_record.administered?
         t("vaccinations.flash.given")
@@ -122,10 +126,10 @@ def handle_confirm
   end
 
   def finish_wizard_path
-    if @draft_vaccination_record.editing?
-      programme_vaccination_record_path(@programme, @vaccination_record)
-    else
+    if @session.today?
       session_vaccinations_path(@session)
+    else
+      programme_vaccination_record_path(@programme, @vaccination_record)
     end
   end
 

spec/features/edit_vaccination_record_spec.rb

@@ -260,6 +260,7 @@ def and_an_hpv_programme_is_underway
     @session =
       create(
         :session,
+        :completed,
         organisation: @organisation,
         programme: @programme,
         location:

spec/features/hpv_vaccination_administered_spec.rb

@@ -46,6 +46,9 @@
     then_i_see_the_record_vaccinations_page
     and_a_success_message
 
+    when_i_go_back
+    and_i_save_changes
+
     when_i_go_to_the_patient
     then_i_see_that_the_status_is_vaccinated
     and_i_see_the_vaccination_details
@@ -180,6 +183,14 @@ def and_a_success_message
     )
   end
 
+  def when_i_go_back
+    visit draft_vaccination_record_path("confirm")
+  end
+
+  def and_i_save_changes
+    click_button "Save changes"
+  end
+
   def when_i_go_to_the_patient
     click_link @patient.full_name
   end
@@ -189,7 +200,7 @@ def then_i_see_that_the_status_is_vaccinated
   end
 
   def and_i_see_the_vaccination_details
-    expect(page).to have_content("Vaccination details")
+    expect(page).to have_content("Vaccination details").once
   end
 
   def when_vaccination_confirmations_are_sent