Validation: Making Product name unique ignoring the fraction_units.

Making the sku_version.units unique for a product across stock_keeping_units.

Both respecting the validity

barker/alembic/versions/0e326930b8a4_temporal_products_fixed.py

@@ -34,7 +34,7 @@ def upgrade():
     )
 
     op.create_exclude_constraint(
-        "uq_product_versions_product_id",
+        op.f("uq_product_versions_product_id"),
         "product_versions",
         (prod.c.product_id, "="),
         (func.daterange(prod.c.valid_from, prod.c.valid_till, text("'[]'")), "&&"),

barker/alembic/versions/8260414066d6_index.py

@@ -0,0 +1,156 @@
+"""index
+
+Revision ID: 8260414066d6
+Revises: 5cb65066be86
+Create Date: 2026-02-13 06:22:39.926120
+
+"""
+
+import sqlalchemy as sa
+
+from alembic import op
+
+
+# revision identifiers, used by Alembic.
+revision = "8260414066d6"
+down_revision = "5cb65066be86"
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # 1) Add the column (nullable for backfill)
+    op.add_column("sku_versions", sa.Column("product_id", sa.UUID(), nullable=True))
+
+    # 2) Define lightweight table objects (no autoload; explicit columns only)
+    sku_versions = sa.Table(
+        "sku_versions",
+        sa.MetaData(),
+        sa.Column("id", sa.UUID(), primary_key=True),
+        sa.Column("sku_id", sa.UUID(), nullable=False),
+        sa.Column("product_id", sa.UUID(), nullable=True),
+        sa.Column("valid_from", sa.Date(), nullable=True),
+        sa.Column("valid_till", sa.Date(), nullable=True),
+        sa.Column("units", sa.Unicode(), nullable=False),
+    )
+
+    stock_keeping_units = sa.Table(
+        "stock_keeping_units",
+        sa.MetaData(),
+        sa.Column("id", sa.UUID(), primary_key=True),
+        sa.Column("product_id", sa.UUID(), nullable=False),
+    )
+
+    # 3) Backfill via SQLAlchemy Core UPDATE..SET..(SELECT ...)
+    product_id_subq = (
+        sa.select(stock_keeping_units.c.product_id)
+        .where(stock_keeping_units.c.id == sku_versions.c.sku_id)
+        .scalar_subquery()
+    )
+
+    backfill_stmt = (
+        sa.update(sku_versions).values(product_id=product_id_subq).where(sku_versions.c.product_id.is_(None))
+    )
+    op.execute(backfill_stmt)
+
+    # 5) Enforce NOT NULL at schema level
+    op.alter_column("sku_versions", "product_id", nullable=False)
+
+    # 6) Trigger keeps product_id in sync when sku_id changes
+    op.execute(
+        sa.text(
+            """
+            CREATE OR REPLACE FUNCTION sku_versions_set_product_id()
+            RETURNS trigger LANGUAGE plpgsql AS $$
+            BEGIN
+              SELECT s.product_id INTO NEW.product_id
+              FROM stock_keeping_units s
+              WHERE s.id = NEW.sku_id;
+
+              IF NEW.product_id IS NULL THEN
+                RAISE EXCEPTION 'Invalid sku_id %, no product found', NEW.sku_id;
+              END IF;
+
+              RETURN NEW;
+            END;
+            $$;
+            """
+        )
+    )
+
+    op.execute(sa.text("DROP TRIGGER IF EXISTS trg_sku_versions_set_product_id ON sku_versions;"))
+    op.execute(
+        sa.text(
+            """
+            CREATE TRIGGER trg_sku_versions_set_product_id
+            BEFORE INSERT OR UPDATE OF sku_id
+            ON sku_versions
+            FOR EACH ROW
+            EXECUTE FUNCTION sku_versions_set_product_id();
+            """
+        )
+    )
+
+    # 7) Exclusion constraint: product_id + units must not overlap in time
+    # daterange(valid_from, valid_till, '[]') overlap operator &&.
+    sv = sa.table(
+        "sku_versions",
+        sa.column("product_id", sa.UUID()),
+        sa.column("units", sa.UUID()),
+        sa.column("valid_from", sa.Date()),
+        sa.column("valid_till", sa.Date()),
+    )
+
+    op.create_exclude_constraint(
+        op.f("uq_sku_versions_product_id_units"),
+        "sku_versions",
+        (sv.c.product_id, "="),
+        (sv.c.units, "="),
+        (sa.func.daterange(sv.c.valid_from, sv.c.valid_till, sa.text("'[]'")), "&&"),
+    )
+
+    prod = sa.table(
+        "product_versions",
+        sa.column("id", sa.UUID()),
+        sa.column("name", sa.Unicode(length=255)),
+        sa.column("fraction_units", sa.Unicode(length=255)),
+        sa.column("valid_from", sa.Date()),
+        sa.column("valid_till", sa.Date()),
+    )
+    # Update the exclude constraint on product_versions to only be on the name and drop fraction_units from it
+    op.drop_constraint("uq_product_versions_name", "product_versions", type_="unique")
+    op.create_exclude_constraint(
+        op.f("uq_product_versions_name"),
+        "product_versions",
+        (prod.c.name, "="),
+        (sa.func.daterange(prod.c.valid_from, prod.c.valid_till, sa.text("'[]'")), "&&"),
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    op.drop_constraint("uq_sku_versions_product_id_units", "sku_versions", type_="exclude")
+
+    # Drop trigger + function
+    op.execute(sa.text("DROP TRIGGER IF EXISTS trg_sku_versions_set_product_id ON sku_versions;"))
+    op.execute(sa.text("DROP FUNCTION IF EXISTS sku_versions_set_product_id();"))
+
+    # Drop column
+    op.drop_column("sku_versions", "product_id")
+
+    prod = sa.table(
+        "product_versions",
+        sa.column("id", sa.UUID()),
+        sa.column("name", sa.Unicode(length=255)),
+        sa.column("fraction_units", sa.Unicode(length=255)),
+        sa.column("valid_from", sa.Date()),
+        sa.column("valid_till", sa.Date()),
+    )
+    op.drop_constraint("uq_product_versions_name", "product_versions", type_="unique")
+    op.create_exclude_constraint(
+        "uq_product_versions_name",
+        "product_versions",
+        (prod.c.name, "="),
+        (prod.c.units, "="),
+        (sa.func.daterange(prod.c.valid_from, prod.c.valid_till, sa.text("'[]'")), "&&"),
+    )

barker/barker/models/sku_version.py

@@ -8,7 +8,7 @@ from typing import TYPE_CHECKING
 
 from sqlalchemy import Boolean, Date, ForeignKey, Numeric, Unicode, Uuid, func, text
 from sqlalchemy.dialects import postgresql
-from sqlalchemy.orm import Mapped, mapped_column, relationship
+from sqlalchemy.orm import Mapped, mapped_column, relationship, validates
 
 from ..db.base_class import reg
 
@@ -26,6 +26,14 @@ class SkuVersion:
         Uuid, primary_key=True, insert_default=uuid.uuid4, server_default=text("gen_random_uuid()")
     )
     sku_id: Mapped[uuid.UUID] = mapped_column(Uuid, ForeignKey("stock_keeping_units.id"), nullable=False)
+    # DB column is "product_id", but ORM attribute is private: "_product_id"
+    _product_id: Mapped[uuid.UUID] = mapped_column(
+        "product_id",
+        Uuid,
+        nullable=False,
+        repr=False,  # hides in dataclass repr
+        init=False,  # not part of __init__ signature (dataclass)
+    )
     units: Mapped[str] = mapped_column(
         Unicode, nullable=False
     )  # Need to have logic in the application to handle unit uniqueness since we don't have product_id here
@@ -56,8 +64,24 @@ class SkuVersion:
             (sku_id, "="),
             (func.daterange(valid_from, valid_till, text("'[]'")), "&&"),
         ),
+        # product-level uniqueness per time range
+        postgresql.ExcludeConstraint(
+            (_product_id, "="),
+            (units, "="),
+            (func.daterange(valid_from, valid_till, text("'[]'")), "&&"),
+            name="uq_sku_versions_product_units_time",
+            using="gist",
+        ),
     )
 
+    @validates("_product_id")
+    def _prevent_writes_to_product_id(self, key, value):
+        """
+        This column is integrity-only. We never accept app-side writes.
+        DB trigger sets it.
+        """
+        raise ValueError("product_id is managed by the database and must not be set in application code.")
+
     def __init__(
         self,
         units: str = "",

barker/barker/routers/reports/sale_report.py

@@ -60,7 +60,7 @@ def get_sale_report(
 
 def get_sale(start_date: date, finish_date: date, id_: uuid.UUID | None, db: Session) -> list[SaleReportItem]:
     day = func.cast(
-        Voucher.date + timedelta(minutes=settings.TIMEZONE_OFFSET_MINUTES - settings.NEW_DAY_OFFSET_MINUTES), Date
+        Kot.date + timedelta(minutes=settings.TIMEZONE_OFFSET_MINUTES - settings.NEW_DAY_OFFSET_MINUTES), Date
     ).label("day")
     product_version_onclause = _pv_onclause(day)
     query = (