Create a new table to warehouse the monthly billing numbers

app/dao/monthly_billing_dao.py

@@ -0,0 +1,6 @@
+from app import db
+
+
+def update_monthly_billing(monthly_billing):
+    db.session.add(monthly_billing)
+    db.session.commit()

app/models.py

@@ -4,7 +4,6 @@ import datetime
 from flask import url_for, current_app
 
 from sqlalchemy.ext.associationproxy import association_proxy
-from sqlalchemy.ext.hybrid import hybrid_property
 from sqlalchemy.dialects.postgresql import (
     UUID,
     JSON
@@ -1246,3 +1245,19 @@ class LetterRateDetail(db.Model):
     letter_rate = db.relationship('LetterRate', backref='letter_rates')
     page_total = db.Column(db.Integer, nullable=False)
     rate = db.Column(db.Numeric(), nullable=False)
+
+
+class MonthlyBilling(db.Model):
+    __tablename__ = 'monthly_billing'
+
+    id = db.Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    service_id = db.Column(UUID(as_uuid=True), db.ForeignKey('services.id'), index=True, nullable=False)
+    service = db.relationship('Service', backref='monthly_billing')
+    month = db.Column(db.String, nullable=False)
+    year = db.Column(db.Float(asdecimal=False), nullable=False)
+    notification_type = db.Column(notification_types, nullable=False)
+    monthly_totals = db.Column(JSON, nullable=False)
+
+    __table_args__ = (
+        UniqueConstraint('service_id', 'month', 'year', 'notification_type', name='uix_monthly_billing'),
+    )

migrations/versions/0109_monthly_billing.py

@@ -0,0 +1,37 @@
+"""empty message
+
+Revision ID: 0109_monthly_billing
+Revises: 0108_change_logo_not_nullable
+Create Date: 2017-07-13 14:35:03.183659
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '0109_monthly_billing'
+down_revision = '0108_change_logo_not_nullable'
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+
+def upgrade():
+
+    op.create_table('monthly_billing',
+                    sa.Column('id', postgresql.UUID(as_uuid=True), nullable=False),
+                    sa.Column('service_id', postgresql.UUID(as_uuid=True), nullable=False),
+                    sa.Column('month', sa.String(), nullable=False),
+                    sa.Column('year', sa.Float(), nullable=False),
+                    sa.Column('notification_type',
+                              postgresql.ENUM('email', 'sms', 'letter', name='notification_type', create_type=False),
+                              nullable=False),
+                    sa.Column('monthly_totals', postgresql.JSON(), nullable=False),
+                    sa.ForeignKeyConstraint(['service_id'], ['services.id'], ),
+                    sa.PrimaryKeyConstraint('id')
+                    )
+    op.create_index(op.f('ix_monthly_billing_service_id'), 'monthly_billing', ['service_id'], unique=False)
+    op.create_index(op.f('uix_monthly_billing'), 'monthly_billing', ['service_id', 'month', 'year', 'notification_type'], unique=True)
+
+
+def downgrade():
+    op.drop_table('monthly_billing')

tests/app/dao/test_monthly_billing.py

@@ -0,0 +1,33 @@
+import uuid
+
+import pytest
+from sqlalchemy.exc import IntegrityError
+
+from app.dao.monthly_billing_dao import update_monthly_billing
+from app.models import MonthlyBilling
+
+
+def test_add_monthly_billing_only_allows_one_row_per_service_month_type(sample_service):
+    first = MonthlyBilling(id=uuid.uuid4(),
+                           service_id=sample_service.id,
+                           notification_type='sms',
+                           month='January',
+                           year='2017',
+                           monthly_totals={'billing_units': 100,
+                                           'rate': 0.0158})
+
+    second = MonthlyBilling(id=uuid.uuid4(),
+                            service_id=sample_service.id,
+                            notification_type='sms',
+                            month='January',
+                            year='2017',
+                            monthly_totals={'billing_units': 50,
+                                            'rate': 0.0162})
+
+    update_monthly_billing(first)
+    with pytest.raises(IntegrityError):
+        update_monthly_billing(second)
+        monthly = MonthlyBilling.query.all()
+        assert len(monthly) == 1
+        assert monthly[0].monthly_totals == {'billing_units': 100,
+                                             'rate': 0.0158}