fix: add Parameter model for lane_op

corepos/db/common/op.py

@@ -27,6 +27,24 @@ Common schema for operational data models
 import sqlalchemy as sa
 
 
+class ParameterBase:
+    """
+    Base class for Parameter models, shared by Office + Lane.
+    """
+    store_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
+
+    lane_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
+
+    param_key = sa.Column(sa.String(length=100), primary_key=True, nullable=False)
+
+    param_value = sa.Column(sa.String(length=255), nullable=True)
+
+    is_array = sa.Column(sa.Boolean(), nullable=True)
+
+    def __str__(self):
+        return f"{self.store_id}-{self.lane_id} {self.param_key}"
+
+
 class EmployeeBase:
     """
     Base class for Employee models, shared by Office + Lane.

corepos/db/lane_op/model.py

@@ -33,6 +33,13 @@ from corepos.db.common import op as common
 Base = orm.declarative_base()
 
 
+class Parameter(common.ParameterBase, Base):
+    """
+    Data model for ``parameters`` table.
+    """
+    __tablename__ = 'parameters'
+
+
 class Employee(common.EmployeeBase, Base):
     """
     Data model for ``employees`` table.

corepos/db/office_op/model.py

@@ -56,25 +56,12 @@ class StringableDateTime(sa.TypeDecorator):
         raise NotImplementedError
 
 
-class Parameter(Base):
+class Parameter(common.ParameterBase, Base):
     """
-    Represents a "parameter" value.
+    Data model for ``parameters`` table.
     """
     __tablename__ = 'parameters'
 
-    store_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
-
-    lane_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
-
-    param_key = sa.Column(sa.String(length=100), primary_key=True, nullable=False)
-
-    param_value = sa.Column(sa.String(length=255), nullable=True)
-
-    is_array = sa.Column(sa.Boolean(), nullable=True)
-
-    def __str__(self):
-        return "{}-{} {}".format(self.store_id, self.lane_id, self.param_key)
-
 
 class TableSyncRule(Base):
     """