mercadodevida/work/artifacts/F-193/implementer.md

F-193 — Implementer Evidence

Feature

Show product expiry and shipping weight on storefront + authoritative variant weight in shipping.

Changes

1. project/migrations/057_product_variant_weight_and_expiry.js (new)

Adds weight_grams column to catalog_product_variants:

• integer, nullable, no default
• CHECK: weight_grams IS NULL OR weight_grams > 0
• After ean column

2. project/src/modules/catalog/domain/variant.ts

Added weightGrams to ProductVariant, NewProductVariant, and ProductVariantPatch.

3. project/src/modules/catalog/infrastructure/pg-variant-repository.ts

• Added weight_grams to VariantRow interface
• Added ['weightGrams', 'weight_grams'] to UPDATABLE array
• Updated create() to INSERT weight_grams
• Updated toVariant() to map weight_grams → weightGrams

4. project/src/modules/catalog/api/catalog.routes.ts

• Added weightGrams to newVariantSchema (zod, optional, integer >= 1)
• Added weightGrams to serializeVariant() output

5. project/src/modules/checkout/application/checkout-service.ts

• Extended getCartWeightKg parameter type to include variantId
• Updated call site to pass full cart.items (no mapping needed)

6. project/src/modules/checkout/api/checkout.routes.ts

• Rewrote getCartWeightKg to:
  • Fetch variant-level weight_grams from catalog_product_variants
  • Fetch product-level unit_weight_kg as fallback
  • Prefer variant weight (g → kg) when available
  • Fall back to product weight (kg) when variant weight is null

7. project/frontend/src/lib/api.ts

• Added weightGrams: number | null to ProductVariant interface

8. project/frontend/src/types/api.ts

• Added expirationDate?: string to Product interface

9. project/frontend/src/app/products/[slug]/page.tsx

Added expiry date and weight display in the price box:

• Caduca: {date} — when product.expirationDate is set
• Peso: {X.Y kg} or Peso: {X g} — from primaryVariant.weightGrams

Existing (no changes needed)

• catalog_products.expiration_date — already exists from migration 038
• catalog_products.unit_weight_kg — already exists as fallback
• ShippingService — already takes cartWeightKg and filters by maxWeightKg
• serializeProduct() — already serializes expirationDate

Verification

Check	Result
npx tsc --noEmit (backend)	0 errors
npx tsc --noEmit (frontend)	0 errors
npm test (backend)	269 passed, 96 skipped
./scripts/verify.sh	OK