Add basic ProductImage data model with importer

Plus some importer tweaks to accommodate a variation on batch mode

rattail/db/alembic/versions/234c79420312_add_product_image.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+"""add product_image
+
+Revision ID: 234c79420312
+Revises: 7ba105af22a7
+Create Date: 2017-02-22 22:43:58.290180
+
+"""
+
+from __future__ import unicode_literals
+
+# revision identifiers, used by Alembic.
+revision = '234c79420312'
+down_revision = u'7ba105af22a7'
+branch_labels = None
+depends_on = None
+
+from alembic import op
+import sqlalchemy as sa
+import rattail.db.types
+from sqlalchemy.dialects import postgresql
+
+
+def upgrade():
+
+    # product_image
+    op.create_table('product_image',
+                    sa.Column('uuid', sa.String(length=32), nullable=False),
+                    sa.Column('product_uuid', sa.String(length=32), nullable=False),
+                    sa.Column('bytes', sa.LargeBinary(), nullable=False),
+                    sa.ForeignKeyConstraint(['product_uuid'], [u'product.uuid'], name=u'product_image_fk_product'),
+                    sa.PrimaryKeyConstraint('uuid')
+    )
+
+
+def downgrade():
+
+    # product_image
+    op.drop_table('product_image')

rattail/db/model/__init__.py

@@ -41,7 +41,7 @@ from .employees import (Employee, EmployeePhoneNumber, EmployeeEmailAddress,
 from .shifts import ScheduledShift, WorkedShift
 
 from .vendors import Vendor, VendorPhoneNumber, VendorEmailAddress, VendorContact
-from .products import Brand, Tax, Product, ProductCode, ProductCost, ProductPrice
+from .products import Brand, Tax, Product, ProductImage, ProductCode, ProductCost, ProductPrice
 from .purchase import (PurchaseBase, PurchaseItemBase, PurchaseCreditBase,
                        Purchase, PurchaseItem, PurchaseCredit)
 

rattail/db/model/products.py

@@ -340,6 +340,33 @@ class Product(Base):
                 return cost
 
 
+class ProductImage(Base):
+    """
+    Contains an image for a product.
+    """
+    __tablename__ = 'product_image'
+    __table_args__ = (
+        sa.ForeignKeyConstraint(['product_uuid'], ['product.uuid'], name='product_image_fk_product'),
+    )
+
+    uuid = uuid_column()
+
+    product_uuid = sa.Column(sa.String(length=32), nullable=False)
+    product = orm.relationship(
+        Product,
+        doc="""
+        Reference to the product which is shown by the image.
+        """,
+        backref=orm.backref(
+            'image',
+            uselist=False,
+            doc="""
+            Reference to the product's image, if any.
+            """))
+
+    bytes = sa.Column(sa.LargeBinary(), nullable=False)
+
+
 @six.python_2_unicode_compatible
 class ProductCode(Base):
     """

rattail/db/util.py

@@ -54,7 +54,10 @@ class QuerySequence(object):
         self.query = query
 
     def __len__(self):
-        return self.query.count()
+        try:
+            return len(self.query)
+        except ValueError:
+            return self.query.count()
 
     def __iter__(self):
         return iter(self.query)

rattail/importing/importers.py

@@ -136,7 +136,9 @@ class Importer(object):
         if kwargs:
             self._setup(**kwargs)
         self.setup()
-        created = updated = deleted = []
+        created = []
+        updated = []
+        deleted = []
 
         # Get complete set of normalized host data.
         if host_data is None:
@@ -173,11 +175,14 @@ class Importer(object):
         self.teardown()
         return created, updated, deleted
 
-    def _import_create_update(self, data):
+    def _import_create_update(self, data, created=None, updated=None):
         """
         Import the given data; create and/or update records as needed.
         """
-        created, updated = [], []
+        if created is None:
+            created = []
+        if updated is None:
+            updated = []
         count = len(data)
         if not count:
             return created, updated

rattail/importing/model.py

@@ -1549,6 +1549,13 @@ class ProductImporter(ToRattail):
         return product
 
 
+class ProductImageImporter(ToRattail):
+    """
+    Data importer for ProductImage model
+    """
+    model_class = model.ProductImage
+
+
 class ProductCodeImporter(ToRattail):
     """
     Data importer for :class:`rattail.db.model.ProductCode`.