first cut of orm, orderlines only [sqlalchemy_classical_mapper]

Author: hjwp

.travis.yml

@@ -2,6 +2,9 @@ dist: xenial
 language: python
 python: 3.8
 
+install:
+- pip3 install sqlalchemy
+
 script:
 - make test
 

orm.py

@@ -0,0 +1,19 @@
+from sqlalchemy import Table, MetaData, Column, Integer, String
+from sqlalchemy.orm import mapper
+
+import model
+
+
+metadata = MetaData()
+
+order_lines = Table(
+    "order_lines",
+    metadata,
+    Column("orderid", String(255), primary_key=True),
+    Column("sku", String(255), primary_key=True),
+    Column("qty", Integer),
+)
+
+
+def start_mappers():
+    mapper(model.OrderLine, order_lines)

test_batches.py

@@ -17,18 +17,22 @@ def make_batch_and_line(sku, batch_qty, line_qty):
         OrderLine("order-123", sku, line_qty),
     )
 
+
 def test_can_allocate_if_available_greater_than_required():
     large_batch, small_line = make_batch_and_line("ELEGANT-LAMP", 20, 2)
     assert large_batch.can_allocate(small_line)
 
+
 def test_cannot_allocate_if_available_smaller_than_required():
     small_batch, large_line = make_batch_and_line("ELEGANT-LAMP", 2, 20)
     assert small_batch.can_allocate(large_line) is False
 
+
 def test_can_allocate_if_available_equal_to_required():
     batch, line = make_batch_and_line("ELEGANT-LAMP", 2, 2)
     assert batch.can_allocate(line)
 
+
 def test_cannot_allocate_if_skus_do_not_match():
     batch = Batch("batch-001", "UNCOMFORTABLE-CHAIR", 100, eta=None)
     different_sku_line = OrderLine("order-123", "EXPENSIVE-TOASTER", 10)