Introduce product details table

alembic/versions/3b61a6fbc6b2_introduce_product_details.py

@@ -0,0 +1,112 @@
+"""introduce product details
+
+Revision ID: 3b61a6fbc6b2
+Revises: 958d7aee2b21
+Create Date: 2026-04-22 11:56:31.223186
+
+"""
+
+import datetime
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = "3b61a6fbc6b2"
+down_revision: Union[str, Sequence[str], None] = "958d7aee2b21"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table(
+        "aps_product_detail",
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
+        sa.Column("name", sa.String(), nullable=False),
+        sa.Column("product_id", sa.Integer(), nullable=False),
+        sa.Column("description", sa.String(), nullable=True),
+        sa.Column("price", sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column(
+            "unit_of_measure",
+            sa.Enum("g", "kg", "l", "piece", native_enum=False),
+            nullable=False,
+        ),
+        sa.Column("allow_fractional", sa.Boolean(), nullable=False),
+        sa.Column("temporarily_unavailable", sa.Boolean(), nullable=False),
+        sa.Column("vat_rate", sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column("valid_from", sa.DateTime(), nullable=False),
+        sa.ForeignKeyConstraint(
+            ["product_id"],
+            ["aps_product.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("name"),
+    )
+
+    # Step 2: Copy data from aps_product to aps_product_detail
+    # Bind the current connection to a temporary session
+    conn = op.get_bind()
+
+    # Fetch all products
+    products = conn.execute(
+        sa.text(
+            "SELECT id, name, price, unit_of_measure, allow_fractional, vat_rate FROM aps_product"
+        )
+    ).fetchall()
+
+    # Insert data into aps_product_detail
+    for product in products:
+        conn.execute(
+            sa.text(
+                """
+                INSERT INTO aps_product_detail
+                (name, product_id, description, price, unit_of_measure, allow_fractional, temporarily_unavailable, vat_rate, valid_from)
+                VALUES (:name, :product_id, :description, :price, :unit_of_measure, :allow_fractional, :temporarily_unavailable, :vat_rate, :valid_from)
+                """
+            ),
+            {
+                "name": product.name,
+                "product_id": product.id,
+                "description": "",
+                "price": product.price,
+                "unit_of_measure": product.unit_of_measure,
+                "allow_fractional": product.allow_fractional,
+                "temporarily_unavailable": False,
+                "vat_rate": product.vat_rate,
+                "valid_from": datetime.datetime(1970, 1, 1, 0, 0, 0),
+            },
+        )
+    with op.batch_alter_table("aps_product") as batch_op:
+        batch_op.drop_column("vat_rate")
+        batch_op.drop_column("name")
+
+        batch_op.drop_column("allow_fractional")
+        batch_op.drop_column("unit_of_measure")
+        batch_op.drop_column("price")
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column(
+        "aps_product",
+        sa.Column("price", sa.NUMERIC(precision=10, scale=2), nullable=False),
+    )
+    op.add_column(
+        "aps_product",
+        sa.Column("unit_of_measure", sa.VARCHAR(length=5), nullable=False),
+    )
+    op.add_column(
+        "aps_product", sa.Column("allow_fractional", sa.BOOLEAN(), nullable=False)
+    )
+    op.add_column(
+        "aps_product",
+        sa.Column("vat_rate", sa.NUMERIC(precision=10, scale=2), nullable=False),
+    )
+    op.add_column("aps_product", sa.Column("name", sa.VARCHAR(), nullable=False))
+    op.drop_table("aps_product_detail")
+    # ### end Alembic commands ###

alembic/versions/958d7aee2b21_initial_model.py

@@ -1,10 +1,11 @@
 """Initial model
 
 Revision ID: 958d7aee2b21
-Revises: 
+Revises:
 Create Date: 2026-01-23 10:10:36.825333
 
 """
+
 from typing import Sequence, Union
 
 from alembic import op
@@ -12,7 +13,7 @@ import sqlalchemy as sa
 
 
 # revision identifiers, used by Alembic.
-revision: str = '958d7aee2b21'
+revision: str = "958d7aee2b21"
 down_revision: Union[str, Sequence[str], None] = None
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None
@@ -21,96 +22,148 @@ depends_on: Union[str, Sequence[str], None] = None
 def upgrade() -> None:
     """Upgrade schema."""
     # ### commands auto generated by Alembic - please adjust! ###
-    op.create_table('aps_account',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_account",
-    sa.Column('name', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.PrimaryKeyConstraint('id'),
+        sa.Column("name", sa.String(), nullable=False),
-    sa.UniqueConstraint('name')
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("name"),
     )
-    op.create_table('aps_area',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_area",
-    sa.Column('name', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('description', sa.String(), nullable=True),
+        sa.Column("name", sa.String(), nullable=False),
-    sa.Column('image_path', sa.String(), nullable=True),
+        sa.Column("description", sa.String(), nullable=True),
-    sa.PrimaryKeyConstraint('id'),
+        sa.Column("image_path", sa.String(), nullable=True),
-    sa.UniqueConstraint('name')
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("name"),
     )
-    op.create_table('aps_user',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_user",
-    sa.Column('username', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('display_name', sa.String(), nullable=False),
+        sa.Column("username", sa.String(), nullable=False),
-    sa.PrimaryKeyConstraint('id'),
+        sa.Column("display_name", sa.String(), nullable=False),
-    sa.UniqueConstraint('username')
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("username"),
     )
-    op.create_table('aps_user_group',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_user_group",
-    sa.Column('name', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('description', sa.String(), nullable=True),
+        sa.Column("name", sa.String(), nullable=False),
-    sa.PrimaryKeyConstraint('id'),
+        sa.Column("description", sa.String(), nullable=True),
-    sa.UniqueConstraint('name')
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("name"),
     )
-    op.create_table('aps_order',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_order",
-    sa.Column('user_id', sa.Integer(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.ForeignKeyConstraint(['user_id'], ['aps_user.id'], ),
+        sa.Column("user_id", sa.Integer(), nullable=False),
-    sa.PrimaryKeyConstraint('id')
+        sa.ForeignKeyConstraint(
+            ["user_id"],
+            ["aps_user.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
     )
-    op.create_table('aps_permission',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_permission",
-    sa.Column('scope', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('action', sa.String(), nullable=False),
+        sa.Column("scope", sa.String(), nullable=False),
-    sa.Column('user_group_id', sa.Integer(), nullable=False),
+        sa.Column("action", sa.String(), nullable=False),
-    sa.ForeignKeyConstraint(['user_group_id'], ['aps_user_group.id'], ),
+        sa.Column("user_group_id", sa.Integer(), nullable=False),
-    sa.PrimaryKeyConstraint('id')
+        sa.ForeignKeyConstraint(
+            ["user_group_id"],
+            ["aps_user_group.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
     )
-    op.create_table('aps_product',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_product",
-    sa.Column('name', sa.String(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('price', sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column("name", sa.String(), nullable=False),
-    sa.Column('unit_of_measure', sa.Enum('g', 'kg', 'l', 'piece', native_enum=False), nullable=False),
+        sa.Column("price", sa.Numeric(precision=10, scale=2), nullable=False),
-    sa.Column('allow_fractional', sa.Boolean(), nullable=False),
+        sa.Column(
-    sa.Column('vat_rate', sa.Numeric(precision=10, scale=2), nullable=False),
+            "unit_of_measure",
-    sa.Column('area_id', sa.Integer(), nullable=False),
+            sa.Enum("g", "kg", "l", "piece", native_enum=False),
-    sa.Column('image_path', sa.String(), nullable=True),
+            nullable=False,
-    sa.ForeignKeyConstraint(['area_id'], ['aps_area.id'], ),
+        ),
-    sa.PrimaryKeyConstraint('id'),
+        sa.Column("allow_fractional", sa.Boolean(), nullable=False),
-    sa.UniqueConstraint('name')
+        sa.Column("vat_rate", sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column("area_id", sa.Integer(), nullable=False),
+        sa.Column("image_path", sa.String(), nullable=True),
+        sa.ForeignKeyConstraint(
+            ["area_id"],
+            ["aps_area.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("name"),
     )
-    op.create_table('aps_user_account_association',
+    op.create_table(
-    sa.Column('user_id', sa.Integer(), nullable=False),
+        "aps_user_account_association",
-    sa.Column('account_id', sa.Integer(), nullable=False),
+        sa.Column("user_id", sa.Integer(), nullable=False),
-    sa.ForeignKeyConstraint(['account_id'], ['aps_account.id'], ),
+        sa.Column("account_id", sa.Integer(), nullable=False),
-    sa.ForeignKeyConstraint(['user_id'], ['aps_user.id'], ),
+        sa.ForeignKeyConstraint(
-    sa.PrimaryKeyConstraint('user_id', 'account_id')
+            ["account_id"],
+            ["aps_account.id"],
+        ),
+        sa.ForeignKeyConstraint(
+            ["user_id"],
+            ["aps_user.id"],
+        ),
+        sa.PrimaryKeyConstraint("user_id", "account_id"),
     )
-    op.create_table('aps_user_user_group_association',
+    op.create_table(
-    sa.Column('user_id', sa.Integer(), nullable=False),
+        "aps_user_user_group_association",
-    sa.Column('user_group_id', sa.Integer(), nullable=False),
+        sa.Column("user_id", sa.Integer(), nullable=False),
-    sa.ForeignKeyConstraint(['user_group_id'], ['aps_user_group.id'], ),
+        sa.Column("user_group_id", sa.Integer(), nullable=False),
-    sa.ForeignKeyConstraint(['user_id'], ['aps_user.id'], ),
+        sa.ForeignKeyConstraint(
-    sa.PrimaryKeyConstraint('user_id', 'user_group_id')
+            ["user_group_id"],
+            ["aps_user_group.id"],
+        ),
+        sa.ForeignKeyConstraint(
+            ["user_id"],
+            ["aps_user.id"],
+        ),
+        sa.PrimaryKeyConstraint("user_id", "user_group_id"),
     )
-    op.create_table('aps_order_item',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_order_item",
-    sa.Column('order_id', sa.Integer(), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('product_id', sa.Integer(), nullable=False),
+        sa.Column("order_id", sa.Integer(), nullable=False),
-    sa.Column('quantity', sa.Numeric(), nullable=False),
+        sa.Column("product_id", sa.Integer(), nullable=False),
-    sa.Column('total_amount', sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column("quantity", sa.Numeric(), nullable=False),
-    sa.ForeignKeyConstraint(['order_id'], ['aps_order.id'], ),
+        sa.Column("total_amount", sa.Numeric(precision=10, scale=2), nullable=False),
-    sa.ForeignKeyConstraint(['product_id'], ['aps_product.id'], ),
+        sa.ForeignKeyConstraint(
-    sa.PrimaryKeyConstraint('id')
+            ["order_id"],
+            ["aps_order.id"],
+        ),
+        sa.ForeignKeyConstraint(
+            ["product_id"],
+            ["aps_product.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
     )
-    op.create_table('aps_transaction',
+    op.create_table(
-    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+        "aps_transaction",
-    sa.Column('type', sa.Enum('order', 'deposit', 'withdrawal', 'expense', native_enum=False), nullable=False),
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
-    sa.Column('quantity', sa.Numeric(precision=10, scale=2), nullable=True),
+        sa.Column(
-    sa.Column('timestamp', sa.DateTime(), nullable=False),
+            "type",
-    sa.Column('total_amount', sa.Numeric(precision=10, scale=2), nullable=False),
+            sa.Enum("order", "deposit", "withdrawal", "expense", native_enum=False),
-    sa.Column('order_id', sa.Integer(), nullable=True),
+            nullable=False,
-    sa.Column('account_id', sa.Integer(), nullable=False),
+        ),
-    sa.ForeignKeyConstraint(['account_id'], ['aps_account.id'], ),
+        sa.Column("quantity", sa.Numeric(precision=10, scale=2), nullable=True),
-    sa.ForeignKeyConstraint(['order_id'], ['aps_order.id'], ),
+        sa.Column("timestamp", sa.DateTime(), nullable=False),
-    sa.PrimaryKeyConstraint('id')
+        sa.Column("total_amount", sa.Numeric(precision=10, scale=2), nullable=False),
+        sa.Column("order_id", sa.Integer(), nullable=True),
+        sa.Column("account_id", sa.Integer(), nullable=False),
+        sa.ForeignKeyConstraint(
+            ["account_id"],
+            ["aps_account.id"],
+        ),
+        sa.ForeignKeyConstraint(
+            ["order_id"],
+            ["aps_order.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
     )
     # ### end Alembic commands ###
 
@@ -118,15 +171,15 @@ def upgrade() -> None:
 def downgrade() -> None:
     """Downgrade schema."""
     # ### commands auto generated by Alembic - please adjust! ###
-    op.drop_table('aps_transaction')
+    op.drop_table("aps_transaction")
-    op.drop_table('aps_order_item')
+    op.drop_table("aps_order_item")
-    op.drop_table('aps_user_user_group_association')
+    op.drop_table("aps_user_user_group_association")
-    op.drop_table('aps_user_account_association')
+    op.drop_table("aps_user_account_association")
-    op.drop_table('aps_product')
+    op.drop_table("aps_product")
-    op.drop_table('aps_permission')
+    op.drop_table("aps_permission")
-    op.drop_table('aps_order')
+    op.drop_table("aps_order")
-    op.drop_table('aps_user_group')
+    op.drop_table("aps_user_group")
-    op.drop_table('aps_user')
+    op.drop_table("aps_user")
-    op.drop_table('aps_area')
+    op.drop_table("aps_area")
-    op.drop_table('aps_account')
+    op.drop_table("aps_account")
     # ### end Alembic commands ###

src/allmende_payment_system/api/admin.py

@@ -1,7 +1,8 @@
+import datetime
 from typing import Annotated
 
 from fastapi import APIRouter, File, Form, HTTPException, Request
-from sqlalchemy import select
+from sqlalchemy import func, select
 from sqlalchemy.exc import IntegrityError
 from starlette import status
 from starlette.responses import RedirectResponse
@@ -13,6 +14,7 @@ from allmende_payment_system.models import (
     Area,
     Permission,
     Product,
+    ProductDetails,
     Transaction,
     User,
     UserGroup,
@@ -234,9 +236,14 @@ async def edit_product_post(
         select(Product).where(Product.id == product_id)
     ).scalar_one()
 
-    for field_name, data in product_data.model_dump().items():
+    new_details = ProductDetails(
-        setattr(product, field_name, data)
+        valid_from=func.now(),
+    )
 
+    for field_name, data in product_data.model_dump().items():
+        setattr(new_details, field_name, data)
+
+    product.details_history.append(new_details)
     session.flush()
 
     return RedirectResponse(
@@ -273,12 +280,15 @@ async def new_product_post(
     if not user.has_permission("product", "edit"):
         raise HTTPException(status_code=403, detail="Insufficient permissions")
 
-    product = Product()
+    product = Product(area_id=product_data.area_id)
+    session.add(product)
+    session.flush()
+
+    product_details = ProductDetails()
+    product.details_history.append(product_details)
 
     for field_name, data in product_data.model_dump().items():
-        setattr(product, field_name, data)
+        setattr(product_details, field_name, data)
-
-    session.add(product)
 
     return RedirectResponse(
         url="/admin/products", status_code=status.HTTP_303_SEE_OTHER

src/allmende_payment_system/api/shop.py

@@ -78,7 +78,7 @@ async def add_to_cart(request: Request, session: SessionDep, user: UserDep):
     product = session.scalars(query).one()
 
     quantity = Decimal(form_data["quantity"])
-    total_amount = product.price * quantity
+    total_amount = product.current_details.price * quantity
 
     order_item = OrderItem(
         product=product, quantity=quantity, total_amount=total_amount

src/allmende_payment_system/models.py

@@ -2,7 +2,7 @@ import datetime
 import decimal
 import typing
 
-from sqlalchemy import Column, ForeignKey, Numeric, Table, select
+from sqlalchemy import Column, ForeignKey, Numeric, Table, func, select
 from sqlalchemy.exc import NoResultFound
 from sqlalchemy.orm import (
     DeclarativeBase,
@@ -135,23 +135,59 @@ class Area(Base):
     products: Mapped[list["Product"]] = relationship("Product")
 
 
-class Product(Base):
+class ProductDetails(Base):
-    __tablename__ = TABLE_PREFIX + "product"
+    """Describes details of the product that can change over time like price, unit of measure, vat rate, etc."""
+
+    __tablename__ = TABLE_PREFIX + "product_detail"
     id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
     name: Mapped[str] = mapped_column(nullable=False, unique=True)
 
+    product_id: Mapped[int] = mapped_column(ForeignKey(TABLE_PREFIX + "product.id"))
+    product: Mapped["Product"] = relationship("Product")
+
+    description: Mapped[str] = mapped_column(nullable=True)
+
     price: Mapped[decimal.Decimal] = mapped_column(Numeric(10, 2))
     unit_of_measure: Mapped[UnitsOfMeasure] = mapped_column(nullable=False)
     allow_fractional: Mapped[bool] = mapped_column(nullable=False, default=True)
 
+    temporarily_unavailable: Mapped[bool] = mapped_column(nullable=False, default=False)
+
     # TODO: limit this to actually used vat rates?
     vat_rate: Mapped[decimal.Decimal] = mapped_column(Numeric(10, 2))
 
+    valid_from: Mapped[datetime.datetime] = mapped_column(
+        nullable=False, default=datetime.datetime(1970, 1, 1, 0, 0, 0)
+    )
+
+
+class Product(Base):
+    __tablename__ = TABLE_PREFIX + "product"
+    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
+
     area_id: Mapped[int] = mapped_column(ForeignKey(TABLE_PREFIX + "area.id"))
     area: Mapped["Area"] = relationship("Area", back_populates="products")
 
     image_path: Mapped[str] = mapped_column(nullable=True)
 
+    details_history: Mapped[list["ProductDetails"]] = relationship(
+        "ProductDetails", cascade="all, delete-orphan", back_populates="product"
+    )
+    current_details: Mapped["ProductDetails"] = relationship(
+        "ProductDetails",
+        primaryjoin="and_(Product.id == ProductDetails.product_id, ProductDetails.valid_from <= func.now())",
+        order_by="ProductDetails.valid_from.desc()",
+        uselist=False,
+        viewonly=True,
+    )
+
+    @classmethod
+    def create(cls, area_id: int | None = None, **kwargs):
+        details = ProductDetails(**kwargs, valid_from=func.now())
+        product = cls(area_id=area_id)
+        product.details_history.append(details)
+        return product
+
 
 class Order(Base):
     __tablename__ = TABLE_PREFIX + "order"
@@ -217,7 +253,7 @@ class OrderItem(Base):
             raise ValueError("Quantity must be positive.")
 
         self.quantity = new_quantity
-        self.total_amount = self.product.price * new_quantity
+        self.total_amount = self.product.current_details.price * new_quantity
 
 
 TransactionTypes = typing.Literal[

src/allmende_payment_system/templates/area.html.jinja

@@ -12,19 +12,12 @@
         <div class="col-md-6 col-lg-4">
             <div class="card h-100 border-0 shadow-sm">
                 <a href="#" class="text-decoration-none text-dark">
-                    {#<!-- Product Image -->
-                    <img
-                        src="/static/img/{{ product.image_path if product.image_path else 'placeholder.jpg' }}"
-                        alt="{{ product.name }}"
-                        class="card-img-top img-fluid rounded-top"
-                        style="height: 100px; object-fit: cover;"
-                    >#}
                     <!-- Product Details -->
                     <div class="card-body">
-                        <h5 class="card-title mb-2">{{ product.name }}</h5>
+                        <h5 class="card-title mb-2">{{ product.current_details.name }}</h5>
-                        <p class="card-text text-muted small mb-3">{{ product.description }}</p>
+                        <p class="card-text text-muted small mb-3">{{ product.current_details.description }}</p>
                         <div class="d-flex justify-content-between align-items-center">
-                            <span class="fw-bold">{{ product.price|format_number }} € pro {{ product.unit_of_measure|units_of_measure_de }}</span>
+                            <span class="fw-bold">{{ product.current_details.price|format_number }} € pro {{ product.current_details.unit_of_measure|units_of_measure_de }}</span>
                             <button class="btn btn-sm btn-outline-primary"
                                     data-bs-toggle="modal"
                                     data-bs-target="#productModal{{ product.id }}">
@@ -43,45 +36,38 @@
                 <div class="modal-content">
                     <form method="POST" action="/shop/cart/add">
                         <div class="modal-header">
-                            <h5 class="modal-title" id="productModalLabel{{ product.id }}">{{ product.name }}</h5>
+                            <h5 class="modal-title" id="productModalLabel{{ product.id }}">{{ product.current_details.name }}</h5>
                             <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
                         </div>
                         <div class="modal-body">
-                            {#<!-- Product Image -->
-                            <img
-                                src="/static/img/{{ product.image_path if product.image_path else 'placeholder.jpg' }}"
-                                alt="{{ product.name }}"
-                                class="img-fluid rounded mb-3"
-                                style="max-height: 200px; width: 100%; object-fit: cover;"
-                            >#}
 
                             <!-- Product Description -->
-                            <p class="text-muted mb-3">{{ product.description }}</p>
+                            <p class="text-muted mb-3">{{ product.current_details.description }}</p>
 
                             <!-- Price -->
                             <div class="mb-3">
-                                <h6 class="fw-bold">Preis: {{ product.price|format_number }} € pro {{ product.unit_of_measure|units_of_measure_de }}</h6>
+                                <h6 class="fw-bold">Preis: {{ product.current_details.price|format_number }} € pro {{ product.current_details.unit_of_measure|units_of_measure_de }}</h6>
                             </div>
 
                             <!-- Quantity Selector -->
                             <input type="hidden" name="product_id" value="{{ product.id }}">
                             <input type="hidden" name="area_id" value="{{ area.id }}">
                             <div class="mb-3">
-                                <label for="quantity{{ product.id }}" class="form-label">Menge{% if product.unit_of_measure != 'piece' %} (in {{product.unit_of_measure}}){% endif %}</label>
+                                <label for="quantity{{ product.id }}" class="form-label">Menge{% if product.current_details.unit_of_measure != 'piece' %} (in {{product.current_details.unit_of_measure}}){% endif %}</label>
                                 <input type="number"
                                        class="form-control"
                                        id="quantity{{ product.id }}"
                                        name="quantity"
                                        value="1"
-                                       {% if product.allow_fractional %}min="0.01"{% else %}min="1"{% endif %}
+                                       {% if product.current_details.allow_fractional %}min="0.01"{% else %}min="1"{% endif %}
                                        max="999"
-                                       {% if product.allow_fractional %}step="0.01"{% else %}step="1"{% endif %}
+                                       {% if product.current_details.allow_fractional %}step="0.01"{% else %}step="1"{% endif %}
                                        oninput="updateTotal{{ product.id }}(this.value)"
                                        style="max-width: 150px;">
                             </div>
                             <!-- Total Price -->
                             <div class="mb-3">
-                                <h6>Gesamt: <span id="total{{ product.id }}" class="fw-bold">{{ '%.2f' | format(product.price) }} €</span></h6>
+                                <h6>Gesamt: <span id="total{{ product.id }}" class="fw-bold">{{ '%.2f' | format(product.current_details.price) }} €</span></h6>
                             </div>
 
                         </div>
@@ -98,7 +84,7 @@
         {# TODO: Make this a global function #}
         <script>
             function updateTotal{{ product.id }}(quantity) {
-                const price = {{ product.price }};
+                const price = {{ product.current_details.price }};
                 const total = (price * quantity).toFixed(2);
                 document.getElementById('total{{ product.id }}').textContent = total + ' €';
             }

src/allmende_payment_system/templates/order.html.jinja

@@ -29,7 +29,7 @@
                         {% set total.value = total.value + subtotal %}
                         <tr>
                             <td>
-                                <div class="fw-semibold">{{ item.product.name }}</div>
+                                <div class="fw-semibold">{{ item.product.current_details.name }}</div>
                                 <div class="text-muted small">{{ item.description or '' }}</div>
                             </td>
                             <td class="text-center" style="width:180px;">
@@ -38,19 +38,19 @@
                                     <input
                                         type="number"
                                         name="quantity"
-                                        value="{% if item.product.allow_fractional %}{{ item.quantity | format_number }}{% else %}{{ item.quantity | int }}{% endif %}"
+                                        value="{% if item.product.current_details.allow_fractional %}{{ item.quantity | format_number }}{% else %}{{ item.quantity | int }}{% endif %}"
-                                        {% if item.product.allow_fractional %}min="0.01" step="0.01"{% else %}min="1" step="1"{% endif %}
+                                        {% if item.product.current_details.allow_fractional %}min="0.01" step="0.01"{% else %}min="1" step="1"{% endif %}
                                         class="form-control form-control-sm me-2"
                                         style="width:80px;"
                                         required>
-                                    {% if item.product.unit_of_measure != 'piece' %}<span class="text-muted small ms-1 me-2">{{ item.product.unit_of_measure }}</span>{% endif %}
+                                    {% if item.product.current_details.unit_of_measure != 'piece' %}<span class="text-muted small ms-1 me-2">{{ item.product.unit_of_measure }}</span>{% endif %}
                                     <button class="btn btn-sm btn-outline-secondary" type="submit">Aktualisieren</button>
                                 </form>
                                 {% else %}
-                                {{ item.quantity | format_number }}{% if item.product.unit_of_measure != 'piece' %} {{ item.product.unit_of_measure }}{% endif %}
+                                {{ item.quantity | format_number }}{% if item.product.current_details.unit_of_measure != 'piece' %} {{ item.product.unit_of_measure }}{% endif %}
                                 {% endif %}
                             </td>
-                            <td class="text-end">{{ item.product.price | format_number }} €</td>
+                            <td class="text-end">{{ item.product.current_details.price | format_number }} €</td>
                             <td class="text-end">{{ item.total_amount | format_number }} €</td>
                             <td class="text-end">
                                 {% if is_cart %}<a href="/shop/cart/remove/{{ item.id }}" class="btn btn-sm btn-outline-danger">Entfernen</a>{% endif %}

src/allmende_payment_system/templates/product_edit.html.jinja

@@ -7,34 +7,34 @@
     <form method="post">
         <div class="mb-3">
             <label for="name" class="form-label">Name</label>
-            <input type="text" class="form-control" id="name" name="name" {% if edit_mode %}value="{{ product.name }}"{% endif %} required>
+            <input type="text" class="form-control" id="name" name="name" {% if edit_mode %}value="{{ product.current_details.name }}"{% endif %} required>
         </div>
 
         <div class="mb-3">
             <label for="price" class="form-label">Preis</label>
-            <input type="number" step="0.01" class="form-control" id="price" name="price" {% if edit_mode %}value="{{ product.price }}"{% endif %} required>
+            <input type="number" step="0.01" class="form-control" id="price" name="price" {% if edit_mode %}value="{{ product.current_details.price }}"{% endif %} required>
         </div>
 
         <div class="mb-3">
             <label for="unit_of_measure" class="form-label">Einheit</label>
             <select class="form-select" id="unit_of_measure" name="unit_of_measure" required>
-                <option value="g" {% if edit_mode and product.unit_of_measure == 'g' %}selected{% endif %}>g</option>
+                <option value="g" {% if edit_mode and product.current_details.unit_of_measure == 'g' %}selected{% endif %}>g</option>
-                <option value="kg" {% if edit_mode and product.unit_of_measure == 'kg' %}selected{% endif %}>kg</option>
+                <option value="kg" {% if edit_mode and product.current_details.unit_of_measure == 'kg' %}selected{% endif %}>kg</option>
-                <option value="l" {% if edit_mode and product.unit_of_measure == 'l' %}selected{% endif %}>l</option>
+                <option value="l" {% if edit_mode and product.current_details.unit_of_measure == 'l' %}selected{% endif %}>l</option>
-                <option value="piece" {% if edit_mode and product.unit_of_measure == 'piece' %}selected{% endif %}>Stück</option>
+                <option value="piece" {% if edit_mode and product.current_details.unit_of_measure == 'piece' %}selected{% endif %}>Stück</option>
             </select>
         </div>
 
         <div class="mb-3 form-check">
-            <input type="checkbox" class="form-check-input" id="allow_fractional" name="allow_fractional" {% if edit_mode and product.allow_fractional %}checked{% endif %}>
+            <input type="checkbox" class="form-check-input" id="allow_fractional" name="allow_fractional" {% if edit_mode and product.current_details.allow_fractional %}checked{% endif %}>
             <label class="form-check-label" for="allow_fractional">Bruchteile erlauben</label>
         </div>
 
         <div class="mb-3">
             <label for="vat_rate" class="form-label">MwSt-Satz</label>
             <select class="form-select" id="vat_rate" name="vat_rate" required>
-                <option value="7" {% if edit_mode and product.vat_rate == '7' %}selected{% endif %}>7 %</option>
+                <option value="7" {% if edit_mode and product.current_details.vat_rate == '7' %}selected{% endif %}>7 %</option>
-                <option value="19" {% if edit_mode and product.vat_rate == '19' %}selected{% endif %}>19 %</option>
+                <option value="19" {% if edit_mode and product.current_details.vat_rate == '19' %}selected{% endif %}>19 %</option>
             </select>
         </div>
 

src/allmende_payment_system/templates/products.html.jinja

@@ -25,11 +25,11 @@
                     {% for product in products %}
                         <tr>
                             <td>{{ product.id }}</td>
-                            <td>{{ product.name }}</td>
+                            <td>{{ product.current_details.name }}</td>
                             <td>{{ product.area.name }}</td>
-                            <td>{{ product.price | format_number}} €</td>
+                            <td>{{ product.current_details.price | format_number}} €</td>
-                            <td>{{ product.unit_of_measure | units_of_measure_de}}</td>
+                            <td>{{ product.current_details.unit_of_measure | units_of_measure_de}}</td>
-                            <td>{{ product.vat_rate | int }} %</td>
+                            <td>{{ product.current_details.vat_rate | int }} %</td>
                             <td class="text-end">
                                 <a class="btn btn-sm btn-primary" href="/admin/products/edit/{{ product.id }}">Bearbeiten</a>
                             </td>

test/test_admin.py

@@ -12,6 +12,7 @@ from allmende_payment_system.models import (
     Area,
     Permission,
     Product,
+    ProductDetails,
     User,
     UserGroup,
 )
@@ -219,9 +220,49 @@ def test_add_product(test_db, client, admin_user):
         follow_redirects=False,
     )
     assert response.status_code == 303
-    product = test_db.execute(
+    product = test_db.execute(select(Product)).scalar()
-        select(Product).where(Product.name == "Test Product")
-    ).scalar()
     assert product is not None
-    assert product.name == "Test Product"
+    assert len(product.details_history) == 1
-    assert product.price == Decimal("9.99")
+    assert product.current_details.name == "Test Product"
+    assert product.current_details.price == Decimal("9.99")
+
+
+def test_change_product(test_db, client, admin_user):
+    area = Area(name="Test Area", description="An area for testing")
+    test_db.add(area)
+    product = Product(
+        area=area,
+    )
+    product.details_history.append(
+        ProductDetails(
+            name="Test Product",
+            price=Decimal("9.99"),
+            unit_of_measure="piece",
+            vat_rate=Decimal("19.00"),
+        )
+    )
+    test_db.add(product)
+    test_db.flush()
+
+    response = client.post(
+        f"/admin/products/edit/{product.id}",
+        data={
+            "name": "Updated Product",
+            "vat_rate": "7.00",
+            "unit_of_measure": "kg",
+            "price": 19.99,
+            "area_id": area.id,
+        },
+        user=admin_user,
+        follow_redirects=False,
+    )
+    assert response.status_code == 303
+
+    updated_product = test_db.execute(
+        select(Product).where(Product.id == product.id)
+    ).scalar()
+
+    assert len(updated_product.details_history) == 2
+    assert updated_product.current_details.name == "Updated Product"
+    assert updated_product.current_details.price == Decimal("19.99")
+    assert updated_product.current_details.price == Decimal("19.99")

test/test_shop.py

@@ -32,9 +32,9 @@ def create_user_with_account(test_db, username: str, balance: float | None = Non
     return user
 
 
-def add_finalized_order_to_user(test_db, user, product) -> Order:
+def add_finalized_order_to_user(test_db, user, product: Product) -> Order:
     order = Order(user=user)
-    total_amount = product.price
+    total_amount = product.current_details.price
     order.items.append(
         OrderItem(product=product, quantity=1, total_amount=total_amount)
     )
@@ -49,7 +49,7 @@ def add_finalized_order_to_user(test_db, user, product) -> Order:
 def product(test_db):
     area = Area(**fake.area())
     test_db.add(area)
-    product = Product(**fake.product())
+    product = Product.create(**fake.product())
     product.area = area
     test_db.add(product)
     test_db.flush()
@@ -96,15 +96,17 @@ def test_edit_item_in_cart(client: APSTestClient, test_db, product):
     cart = test_db.scalar(select(Order))
     assert len(cart.items) == 1
     assert cart.items[0].quantity == 3
-    assert cart.items[0].total_amount == product.price * 3
+    assert cart.items[0].total_amount == product.current_details.price * 3
 
 
-def test_remove_item_from_cart(client: APSTestClient, test_db, product):
+def test_remove_item_from_cart(client: APSTestClient, test_db, product: Product):
 
     user = create_user_with_account(test_db, "test")
 
     user.shopping_cart.items.append(
-        OrderItem(product=product, quantity=2, total_amount=product.price * 2)
+        OrderItem(
+            product=product, quantity=2, total_amount=product.current_details.price * 2
+        )
     )
     test_db.flush()
 
@@ -122,11 +124,15 @@ def test_remove_item_from_cart(client: APSTestClient, test_db, product):
     assert len(test_db.scalars(select(OrderItem)).all()) == 0
 
 
-def test_remove_item_from_cart_wrong_user(client: APSTestClient, test_db, product):
+def test_remove_item_from_cart_wrong_user(
+    client: APSTestClient, test_db, product: Product
+):
     user = create_user_with_account(test_db, "test")
 
     user.shopping_cart.items.append(
-        OrderItem(product=product, quantity=2, total_amount=product.price * 2)
+        OrderItem(
+            product=product, quantity=2, total_amount=product.current_details.price * 2
+        )
     )
     test_db.flush()
 
@@ -144,7 +150,7 @@ def test_remove_item_from_cart_wrong_user(client: APSTestClient, test_db, produc
     assert len(cart.items) == 1
 
 
-def test_finalize_order(client: APSTestClient, test_db, product):
+def test_finalize_order(client: APSTestClient, test_db, product: Product):
 
     user = create_user_with_account(test_db, "test", balance=100.0)
     second_account = Account(name=f"Another account")
@@ -155,7 +161,9 @@ def test_finalize_order(client: APSTestClient, test_db, product):
     user.accounts.append(second_account)
 
     user.shopping_cart.items.append(
-        OrderItem(product=product, quantity=2, total_amount=product.price * 2)
+        OrderItem(
+            product=product, quantity=2, total_amount=product.current_details.price * 2
+        )
     )
     test_db.flush()
 
@@ -170,10 +178,12 @@ def test_finalize_order(client: APSTestClient, test_db, product):
     assert len(user.orders) == 2  # shopping cart + finalized order
 
     assert user.accounts[0].balance == Decimal(100.0)
-    assert user.accounts[1].balance == Decimal(50.0) - (product.price * 2)
+    assert user.accounts[1].balance == Decimal(50.0) - (
+        product.current_details.price * 2
+    )
 
 
-def test_view_order(client: APSTestClient, test_db, product):
+def test_view_order(client: APSTestClient, test_db, product: Product):
     user = create_user_with_account(test_db, "test")
 
     order = add_finalized_order_to_user(test_db, user, product)
@@ -181,10 +191,10 @@ def test_view_order(client: APSTestClient, test_db, product):
     response = client.get(f"/shop/order/{order.id}")
     assert response.status_code == 200
     assert f"Einkauf #{order.id}" in response.text
-    assert product.name in response.text
+    assert product.current_details.name in response.text
 
 
-def test_view_order_wrong_user(client: APSTestClient, test_db, product):
+def test_view_order_wrong_user(client: APSTestClient, test_db, product: Product):
     user = create_user_with_account(test_db, "test")
 
     order = add_finalized_order_to_user(test_db, user, product)