reset model, orm, repo and services to previous chap version

hjwp · hjwp · commit c114941db504 · 2020-01-09T22:11:21.000Z
diff --git a/src/allocation/adapters/orm.py b/src/allocation/adapters/orm.py
@@ -17,17 +17,11 @@
     Column('orderid', String(255)),
 )
 
-products = Table(
-    'products', metadata,
-    Column('sku', String(255), primary_key=True),
-    Column('version_number', Integer, nullable=False, server_default='0'),
-)
-
 batches = Table(
     'batches', metadata,
     Column('id', Integer, primary_key=True, autoincrement=True),
     Column('reference', String(255)),
-    Column('sku', ForeignKey('products.sku')),
+    Column('sku', String(255)),
     Column('_purchased_quantity', Integer, nullable=False),
     Column('eta', Date, nullable=True),
 )
@@ -42,13 +36,10 @@
 
 def start_mappers():
     lines_mapper = mapper(model.OrderLine, order_lines)
-    batches_mapper = mapper(model.Batch, batches, properties={
+    mapper(model.Batch, batches, properties={
         '_allocations': relationship(
             lines_mapper,
             secondary=allocations,
             collection_class=set,
         )
     })
-    mapper(model.Product, products, properties={
-        'batches': relationship(batches_mapper)
-    })
diff --git a/src/allocation/adapters/repository.py b/src/allocation/adapters/repository.py
@@ -1,14 +1,14 @@
 import abc
 from allocation.domain import model
 
+
 class AbstractRepository(abc.ABC):
 
-    @abc.abstractmethod
-    def add(self, product: model.Product):
+    def add(self, batch: model.Batch):
         raise NotImplementedError
 
     @abc.abstractmethod
-    def get(self, sku) -> model.Product:
+    def get(self, reference) -> model.Batch:
         raise NotImplementedError
 
 
@@ -18,8 +18,11 @@ class SqlAlchemyRepository(AbstractRepository):
     def __init__(self, session):
         self.session = session
 
-    def add(self, product):
-        self.session.add(product)
+    def add(self, batch):
+        self.session.add(batch)
+
+    def get(self, reference):
+        return self.session.query(model.Batch).filter_by(reference=reference).one()
 
-    def get(self, sku):
-        return self.session.query(model.Product).filter_by(sku=sku).first()
+    def list(self):
+        return self.session.query(model.Batch).all()
diff --git a/src/allocation/domain/model.py b/src/allocation/domain/model.py
@@ -8,23 +8,15 @@ class OutOfStock(Exception):
     pass
 
 
-class Product:
-
-    def __init__(self, sku: str, batches: List[Batch], version_number: int = 0):
-        self.sku = sku
-        self.batches = batches
-        self.version_number = version_number
-
-    def allocate(self, line: OrderLine) -> str:
-        try:
-            batch = next(
-                b for b in sorted(self.batches) if b.can_allocate(line)
-            )
-            batch.allocate(line)
-            self.version_number += 1
-            return batch.reference
-        except StopIteration:
-            raise OutOfStock(f'Out of stock for sku {line.sku}')
+def allocate(line: OrderLine, batches: List[Batch]) -> str:
+    try:
+        batch = next(
+            b for b in sorted(batches) if b.can_allocate(line)
+        )
+        batch.allocate(line)
+        return batch.reference
+    except StopIteration:
+        raise OutOfStock(f'Out of stock for sku {line.sku}')
 
 
 @dataclass(unsafe_hash=True)
diff --git a/src/allocation/service_layer/services.py b/src/allocation/service_layer/services.py
@@ -11,16 +11,16 @@ class InvalidSku(Exception):
     pass
 
 
+def is_valid_sku(sku, batches):
+    return sku in {b.sku for b in batches}
+
+
 def add_batch(
         ref: str, sku: str, qty: int, eta: Optional[date],
         uow: unit_of_work.AbstractUnitOfWork
 ):
     with uow:
-        product = uow.products.get(sku=sku)
-        if product is None:
-            product = model.Product(sku, batches=[])
-            uow.products.add(product)
-        product.batches.append(model.Batch(ref, sku, qty, eta))
+        uow.batches.add(model.Batch(ref, sku, qty, eta))
         uow.commit()
 
 
@@ -30,9 +30,9 @@ def allocate(
 ) -> str:
     line = OrderLine(orderid, sku, qty)
     with uow:
-        product = uow.products.get(sku=line.sku)
-        if product is None:
+        batches = uow.batches.list()
+        if not is_valid_sku(line.sku, batches):
             raise InvalidSku(f'Invalid sku {line.sku}')
-        batchref = product.allocate(line)
+        batchref = model.allocate(line, batches)
         uow.commit()
     return batchref
