M54: harden operations and demo resilience

backend/app/api/routers/bookings.py

@@ -30,6 +30,7 @@ from app.schemas import (
     ReturnPreviewResult,
 )
 from app.services.audit import record_audit_event
+from app.services.data_quality import open_odometer_regression_issue
 from app.services.returns import preview_vehicle_return, register_vehicle_return
 
 router = APIRouter(prefix="/api/v1/bookings", tags=["bookings"])
@@ -146,8 +147,14 @@ def create_booking(
 ) -> BookingOut:
     if body.ends_at <= body.starts_at:
         raise HTTPException(status_code=422, detail="Booking end must be after its start")
-    customer = db.scalar(select(Customer).where(Customer.public_ref == body.customer_ref))
-    if customer is None or customer.merged_into_customer_id is not None:
+    customer = db.scalar(
+        select(Customer).where(Customer.public_ref == body.customer_ref).with_for_update()
+    )
+    if (
+        customer is None
+        or customer.merged_into_customer_id is not None
+        or customer.anonymized_at is not None
+    ):
         raise HTTPException(status_code=422, detail="Customer is unavailable for booking")
     # Serialise booking creation per vehicle. The overlap check must run after
     # acquiring this lock, otherwise two concurrent requests can both pass it.
@@ -179,7 +186,9 @@ def create_booking(
         status="reserved",
         start_odometer_km=None,
         end_odometer_km=None,
-        requirements_complete=body.requirements_complete,
+        # Requirements are intentionally confirmed in a separate, audited action.
+        # Never allow booking creation to bypass that operational checkpoint.
+        requirements_complete=False,
     )
     db.add(booking)
     db.flush()
@@ -225,6 +234,15 @@ def checkout_booking(
     if active_conflict is not None:
         raise HTTPException(status_code=409, detail="Vehicle already has an active booking")
 
+    correlation_id = uuid.uuid4()
+    before_booking = {
+        "status": booking.status,
+        "start_odometer_km": booking.start_odometer_km,
+    }
+    before_vehicle = {
+        "operational_status": vehicle.operational_status,
+        "odometer_km": vehicle.odometer_km,
+    }
     attention_reasons: list[str] = []
     if body.start_odometer_km < vehicle.odometer_km:
         attention_reasons.append("odometer_regression")
@@ -250,6 +268,18 @@ def checkout_booking(
         completed_by=user.display_name,
     )
     db.add(inspection)
+    if "odometer_regression" in attention_reasons:
+        open_odometer_regression_issue(
+            db,
+            vehicle=vehicle,
+            reading_ref=inspection.public_ref,
+            reading_km=body.start_odometer_km,
+            canonical_km=vehicle.odometer_km,
+            source_type="checkout",
+            related_refs=[booking.public_ref, inspection.public_ref],
+            actor_label=user.display_name,
+            correlation_id=correlation_id,
+        )
     if attention_reasons:
         booking.status = "blocked"
         vehicle.operational_status = (
@@ -269,13 +299,31 @@ def checkout_booking(
         action="booking_checkout_recorded",
         entity_type="booking",
         entity_id=booking.id,
+        correlation_id=correlation_id,
+        before=before_booking,
         after={
             "inspection_ref": inspection.public_ref,
             "booking_status": booking.status,
+            "start_odometer_km": booking.start_odometer_km,
             "vehicle_status": vehicle.operational_status,
             "attention_reasons": attention_reasons,
         },
     )
+    record_audit_event(
+        db,
+        actor_type="user",
+        actor_label=user.display_name,
+        action="vehicle_status_changed",
+        entity_type="vehicle",
+        entity_id=vehicle.id,
+        correlation_id=correlation_id,
+        before=before_vehicle,
+        after={
+            "operational_status": vehicle.operational_status,
+            "odometer_km": vehicle.odometer_km,
+        },
+        metadata={"booking_ref": booking.public_ref, "inspection_ref": inspection.public_ref},
+    )
     db.commit()
     return CheckoutBookingResult(
         booking_ref=booking.public_ref,