Merge pull request #1022 from alphagov/remove-nasty-query-from-dashboard

Remove nasty query from dashboard

app/config.py

@@ -249,6 +249,8 @@ class Config(object):
         }
     }
 
+    FREE_SMS_TIER_FRAGMENT_COUNT = 250000
+
 
 ######################
 # Config overrides ###

app/dao/notification_usage_dao.py

@@ -1,5 +1,6 @@
 from datetime import datetime, timedelta
 
+from flask import current_app
 from sqlalchemy import Float, Integer
 from sqlalchemy import func, case, cast
 from sqlalchemy import literal_column
@@ -11,7 +12,7 @@ from app.models import (NotificationHistory,
                         NOTIFICATION_STATUS_TYPES_BILLABLE,
                         KEY_TYPE_TEST,
                         SMS_TYPE,
-                        EMAIL_TYPE)
+                        EMAIL_TYPE, Service)
 from app.statsd_decorators import statsd
 from app.utils import get_london_month_from_utc_column
 
@@ -158,6 +159,8 @@ def rate_multiplier():
 @statsd(namespace="dao")
 def get_total_billable_units_for_sent_sms_notifications_in_date_range(start_date, end_date, service_id):
 
+    free_sms_limit = Service.free_sms_fragment_limit()
+
     billable_units = 0
     total_cost = 0.0
 
@@ -176,9 +179,15 @@ def get_total_billable_units_for_sent_sms_notifications_in_date_range(start_date
         )
         billable_units_by_rate_boundry = result.scalar()
         if billable_units_by_rate_boundry:
-            billable_units += int(billable_units_by_rate_boundry)
-            total_cost += int(billable_units_by_rate_boundry) * rate_boundary['rate']
-
+            int_billable_units_by_rate_boundry = int(billable_units_by_rate_boundry)
+            if billable_units >= free_sms_limit:
+                total_cost += int_billable_units_by_rate_boundry * rate_boundary['rate']
+            elif billable_units + int_billable_units_by_rate_boundry > free_sms_limit:
+                remaining_free_allowance = abs(free_sms_limit - billable_units)
+                total_cost += ((int_billable_units_by_rate_boundry - remaining_free_allowance) * rate_boundary['rate'])
+            else:
+                total_cost += 0
+            billable_units += int_billable_units_by_rate_boundry
     return billable_units, total_cost
 
 

app/models.py

@@ -217,6 +217,10 @@ class Service(db.Model, Versioned):
             self.can_send_letters = LETTER_TYPE in [p.permission for p in self.permissions]
             self.can_send_international_sms = INTERNATIONAL_SMS_TYPE in [p.permission for p in self.permissions]
 
+    @staticmethod
+    def free_sms_fragment_limit():
+        return current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT']
+
     @classmethod
     def from_json(cls, data):
         """

app/schemas.py

@@ -25,9 +25,8 @@ from notifications_utils.recipients import (
 
 from app import ma
 from app import models
-from app.models import ServicePermission, INTERNATIONAL_SMS_TYPE, SMS_TYPE, LETTER_TYPE, EMAIL_TYPE
+from app.models import ServicePermission, INTERNATIONAL_SMS_TYPE, LETTER_TYPE
 from app.dao.permissions_dao import permission_dao
-from app.dao.service_permissions_dao import dao_fetch_service_permissions
 from app.utils import get_template_instance
 
 
@@ -176,6 +175,7 @@ class ProviderDetailsHistorySchema(BaseSchema):
 
 class ServiceSchema(BaseSchema):
 
+    free_sms_fragment_limit = fields.Method(method_name='get_free_sms_fragment_limit')
     created_by = field_for(models.Service, 'created_by', required=True)
     organisation = field_for(models.Service, 'organisation')
     branding = field_for(models.Service, 'branding')
@@ -183,11 +183,15 @@ class ServiceSchema(BaseSchema):
     permissions = fields.Method("service_permissions")
     override_flag = False
 
+    def get_free_sms_fragment_limit(selfs, service):
+        return service.free_sms_fragment_limit()
+
     def service_permissions(self, service):
         return [p.permission for p in service.permissions]
 
     class Meta:
         model = models.Service
+        dump_only = ['free_sms_fragment_limit']
         exclude = (
             'updated_at',
             'created_at',
@@ -256,6 +260,11 @@ class ServiceSchema(BaseSchema):
 class DetailedServiceSchema(BaseSchema):
     statistics = fields.Dict()
 
+    free_sms_fragment_limit = fields.Method(method_name='get_free_sms_fragment_limit')
+
+    def get_free_sms_fragment_limit(selfs, service):
+        return service.free_sms_fragment_limit()
+
     class Meta:
         model = models.Service
         exclude = (

tests/app/dao/test_notification_usage_dao.py

@@ -2,6 +2,7 @@ import uuid
 from datetime import datetime, timedelta
 
 import pytest
+from flask import current_app
 
 from app.dao.date_util import get_financial_year
 from app.dao.notification_usage_dao import (
@@ -15,12 +16,13 @@ from app.models import (
     Rate,
     NOTIFICATION_DELIVERED,
     NOTIFICATION_STATUS_TYPES_BILLABLE,
-    NOTIFICATION_STATUS_TYPES_NON_BILLABLE,
-    Notification)
+    NOTIFICATION_STATUS_TYPES_NON_BILLABLE)
 from tests.app.conftest import sample_notification, sample_email_template, sample_letter_template, sample_service
 from tests.app.db import create_notification
 from freezegun import freeze_time
 
+from tests.conftest import set_config
+
 
 def test_get_rates_for_year(notify_db, notify_db_session):
     set_up_rate(notify_db, datetime(2016, 5, 18), 0.016)
@@ -266,218 +268,235 @@ def set_up_rate(notify_db, start_date, value):
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_returns_total_billable_units_for_sms_notifications(notify_db, notify_db_session, sample_service):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 0.016)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
 
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, billable_units=1, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, billable_units=2, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, billable_units=3, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, billable_units=4, status=NOTIFICATION_DELIVERED)
+        set_up_rate(notify_db, datetime(2016, 1, 1), 0.016)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, billable_units=1, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, billable_units=2, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, billable_units=3, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, billable_units=4, status=NOTIFICATION_DELIVERED)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 10
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 0.16
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[0] == 10
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[1] == 0.16
 
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_returns_total_billable_units_multiplied_by_multipler_for_sms_notifications(
         notify_db, notify_db_session, sample_service
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, rate_multiplier=1.0, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, rate_multiplier=2.0, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, rate_multiplier=5.0, status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db, notify_db_session, service=sample_service, rate_multiplier=10.0, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, rate_multiplier=1.0, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, rate_multiplier=2.0, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, rate_multiplier=5.0, status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db, notify_db_session, service=sample_service, rate_multiplier=10.0, status=NOTIFICATION_DELIVERED)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 18
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 45
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 18
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 45
 
 
 def test_returns_total_billable_units_multiplied_by_multipler_for_sms_notifications_for_several_rates(
         notify_db, notify_db_session, sample_service
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2)
-    set_up_rate(notify_db, datetime(2016, 10, 1), 4)
-    set_up_rate(notify_db, datetime(2017, 1, 1), 6)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
 
-    eligble_rate_1 = datetime(2016, 2, 1)
-    eligble_rate_2 = datetime(2016, 11, 1)
-    eligble_rate_3 = datetime(2017, 2, 1)
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2)
+        set_up_rate(notify_db, datetime(2016, 10, 1), 4)
+        set_up_rate(notify_db, datetime(2017, 1, 1), 6)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        rate_multiplier=1.0,
-        status=NOTIFICATION_DELIVERED,
-        created_at=eligble_rate_1)
+        eligble_rate_1 = datetime(2016, 2, 1)
+        eligble_rate_2 = datetime(2016, 11, 1)
+        eligble_rate_3 = datetime(2017, 2, 1)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        rate_multiplier=2.0,
-        status=NOTIFICATION_DELIVERED,
-        created_at=eligble_rate_2)
-
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        rate_multiplier=5.0,
-        status=NOTIFICATION_DELIVERED,
-        created_at=eligble_rate_3)
-
-    start = datetime(2016, 1, 1)
-    end = datetime(2018, 1, 1)
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 8
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 40
-
-
-def test_returns_total_billable_units_for_sms_notifications_for_several_rates_where_dates_match_rate_boundary(
-        notify_db, notify_db_session, sample_service
-):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2)
-    set_up_rate(notify_db, datetime(2016, 10, 1), 4)
-    set_up_rate(notify_db, datetime(2017, 1, 1), 6)
-
-    eligble_rate_1_start = datetime(2016, 1, 1, 0, 0, 0, 0)
-    eligble_rate_1_end = datetime(2016, 9, 30, 23, 59, 59, 999)
-    eligble_rate_2_start = datetime(2016, 10, 1, 0, 0, 0, 0)
-    eligble_rate_2_end = datetime(2016, 12, 31, 23, 59, 59, 999)
-    eligble_rate_3_start = datetime(2017, 1, 1, 0, 0, 0, 0)
-    eligble_rate_3_whenever = datetime(2017, 12, 12, 0, 0, 0, 0)
-
-    def make_notification(created_at):
         sample_notification(
             notify_db,
             notify_db_session,
             service=sample_service,
             rate_multiplier=1.0,
             status=NOTIFICATION_DELIVERED,
-            created_at=created_at)
+            created_at=eligble_rate_1)
 
-    make_notification(eligble_rate_1_start)
-    make_notification(eligble_rate_1_end)
-    make_notification(eligble_rate_2_start)
-    make_notification(eligble_rate_2_end)
-    make_notification(eligble_rate_3_start)
-    make_notification(eligble_rate_3_whenever)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            rate_multiplier=2.0,
+            status=NOTIFICATION_DELIVERED,
+            created_at=eligble_rate_2)
 
-    start = datetime(2016, 1, 1)
-    end = datetime(2018, 1, 1)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            rate_multiplier=5.0,
+            status=NOTIFICATION_DELIVERED,
+            created_at=eligble_rate_3)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 6
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 24.0
+        start = datetime(2016, 1, 1)
+        end = datetime(2018, 1, 1)
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 8
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 40
+
+
+def test_returns_total_billable_units_for_sms_notifications_for_several_rates_where_dates_match_rate_boundary(
+        notify_db, notify_db_session, sample_service
+):
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
+
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2)
+        set_up_rate(notify_db, datetime(2016, 10, 1), 4)
+        set_up_rate(notify_db, datetime(2017, 1, 1), 6)
+
+        eligble_rate_1_start = datetime(2016, 1, 1, 0, 0, 0, 0)
+        eligble_rate_1_end = datetime(2016, 9, 30, 23, 59, 59, 999)
+        eligble_rate_2_start = datetime(2016, 10, 1, 0, 0, 0, 0)
+        eligble_rate_2_end = datetime(2016, 12, 31, 23, 59, 59, 999)
+        eligble_rate_3_start = datetime(2017, 1, 1, 0, 0, 0, 0)
+        eligble_rate_3_whenever = datetime(2017, 12, 12, 0, 0, 0, 0)
+
+        def make_notification(created_at):
+            sample_notification(
+                notify_db,
+                notify_db_session,
+                service=sample_service,
+                rate_multiplier=1.0,
+                status=NOTIFICATION_DELIVERED,
+                created_at=created_at)
+
+        make_notification(eligble_rate_1_start)
+        make_notification(eligble_rate_1_end)
+        make_notification(eligble_rate_2_start)
+        make_notification(eligble_rate_2_end)
+        make_notification(eligble_rate_3_start)
+        make_notification(eligble_rate_3_whenever)
+
+        start = datetime(2016, 1, 1)
+        end = datetime(2018, 1, 1)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[0] == 6
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[1] == 24.0
 
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_returns_total_billable_units_for_sms_notifications_ignoring_letters_and_emails(
         notify_db, notify_db_session, sample_service
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
 
-    email_template = sample_email_template(notify_db, notify_db_session, service=sample_service)
-    letter_template = sample_letter_template(sample_service)
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        template=email_template,
-        service=sample_service,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        template=letter_template,
-        service=sample_service,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED
-    )
+        email_template = sample_email_template(notify_db, notify_db_session, service=sample_service)
+        letter_template = sample_letter_template(sample_service)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            template=email_template,
+            service=sample_service,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            template=letter_template,
+            service=sample_service,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED
+        )
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 2
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 5
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 2
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 5
 
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_returns_total_billable_units_for_sms_notifications_for_only_requested_service(
         notify_db, notify_db_session
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
 
-    service_1 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
-    service_2 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
-    service_3 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=service_1,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=service_2,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED)
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=service_3,
-        billable_units=2,
-        status=NOTIFICATION_DELIVERED
-    )
+        service_1 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
+        service_2 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
+        service_3 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=service_1,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=service_2,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=service_3,
+            billable_units=2,
+            status=NOTIFICATION_DELIVERED
+        )
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[0] == 2
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[1] == 5
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[0] == 2
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[1] == 5
 
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_returns_total_billable_units_for_sms_notifications_handling_null_values(
     notify_db, notify_db_session, sample_service
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        billable_units=2,
-        rate_multiplier=None,
-        status=NOTIFICATION_DELIVERED)
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            billable_units=2,
+            rate_multiplier=None,
+            status=NOTIFICATION_DELIVERED)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 2
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 5
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 2
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 5
 
 
 @pytest.mark.parametrize('billable_units, states', ([
@@ -488,57 +507,61 @@ def test_returns_total_billable_units_for_sms_notifications_handling_null_values
 def test_ignores_non_billable_states_when_returning_billable_units_for_sms_notifications(
     notify_db, notify_db_session, sample_service, billable_units, states
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    for state in states:
-        sample_notification(
-            notify_db,
-            notify_db_session,
-            service=sample_service,
-            billable_units=1,
-            rate_multiplier=None,
-            status=state)
+        for state in states:
+            sample_notification(
+                notify_db,
+                notify_db_session,
+                service=sample_service,
+                billable_units=1,
+                rate_multiplier=None,
+                status=state)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
-        start, end, sample_service.id
-    )[0] == billable_units
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
-        start, end, sample_service.id
-    )[1] == billable_units * 2.5
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id
+        )[0] == billable_units
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id
+        )[1] == billable_units * 2.5
 
 
 @freeze_time("2016-01-10 12:00:00.000000")
 def test_restricts_to_time_period_when_returning_billable_units_for_sms_notifications(
     notify_db, notify_db_session, sample_service
 ):
-    set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+    with set_config(current_app, 'FREE_SMS_TIER_FRAGMENT_COUNT', 0):
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        billable_units=1,
-        rate_multiplier=1.0,
-        created_at=datetime.utcnow() - timedelta(minutes=100),
-        status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            billable_units=1,
+            rate_multiplier=1.0,
+            created_at=datetime.utcnow() - timedelta(minutes=100),
+            status=NOTIFICATION_DELIVERED)
 
-    sample_notification(
-        notify_db,
-        notify_db_session,
-        service=sample_service,
-        billable_units=1,
-        rate_multiplier=1.0,
-        created_at=datetime.utcnow() - timedelta(minutes=5),
-        status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=sample_service,
+            billable_units=1,
+            rate_multiplier=1.0,
+            created_at=datetime.utcnow() - timedelta(minutes=5),
+            status=NOTIFICATION_DELIVERED)
 
-    start = datetime.utcnow() - timedelta(minutes=10)
-    end = datetime.utcnow() + timedelta(minutes=10)
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
 
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 1
-    assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[1] == 2.5
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[0] == 1
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id)[1] == 2.5
 
 
 def test_returns_zero_if_no_matching_rows_when_returning_billable_units_for_sms_notifications(
@@ -604,3 +627,86 @@ def test_should_calculate_rate_boundaries_for_billing_query_for_three_relevant_r
     assert rate_boundaries[2]['start_date'] == rate_3_valid_from
     assert rate_boundaries[2]['end_date'] == end_date
     assert rate_boundaries[2]['rate'] == 0.06
+
+
+@freeze_time("2016-01-10 12:00:00.000000")
+def test_deducts_free_tier_from_bill(
+        notify_db, notify_db_session
+):
+    start_value = current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT']
+    try:
+        current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT'] = 1
+
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2.5)
+
+        service_1 = sample_service(notify_db, notify_db_session, service_name=str(uuid.uuid4()))
+
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=service_1,
+            billable_units=1,
+            status=NOTIFICATION_DELIVERED)
+        sample_notification(
+            notify_db,
+            notify_db_session,
+            service=service_1,
+            billable_units=1,
+            status=NOTIFICATION_DELIVERED)
+
+        start = datetime.utcnow() - timedelta(minutes=10)
+        end = datetime.utcnow() + timedelta(minutes=10)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[0] == 2
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, service_1.id)[1] == 2.5
+    finally:
+        current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT'] = start_value
+
+
+@freeze_time("2016-01-10 12:00:00.000000")
+@pytest.mark.parametrize(
+    'free_tier, expected_cost',
+    [(0, 24.0), (1, 22.0), (2, 20.0), (3, 16.0), (4, 12.0), (5, 6.0), (6, 0.0)]
+)
+def test_deducts_free_tier_from_bill_across_rate_boundaries(
+        notify_db, notify_db_session, sample_service, free_tier, expected_cost
+):
+    start_value = current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT']
+    try:
+        current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT'] = free_tier
+        set_up_rate(notify_db, datetime(2016, 1, 1), 2)
+        set_up_rate(notify_db, datetime(2016, 10, 1), 4)
+        set_up_rate(notify_db, datetime(2017, 1, 1), 6)
+
+        eligble_rate_1_start = datetime(2016, 1, 1, 0, 0, 0, 0)
+        eligble_rate_1_end = datetime(2016, 9, 30, 23, 59, 59, 999)
+        eligble_rate_2_start = datetime(2016, 10, 1, 0, 0, 0, 0)
+        eligble_rate_2_end = datetime(2016, 12, 31, 23, 59, 59, 999)
+        eligble_rate_3_start = datetime(2017, 1, 1, 0, 0, 0, 0)
+        eligble_rate_3_whenever = datetime(2017, 12, 12, 0, 0, 0, 0)
+
+        def make_notification(created_at):
+            sample_notification(
+                notify_db,
+                notify_db_session,
+                service=sample_service,
+                rate_multiplier=1.0,
+                status=NOTIFICATION_DELIVERED,
+                created_at=created_at)
+
+        make_notification(eligble_rate_1_start)
+        make_notification(eligble_rate_1_end)
+        make_notification(eligble_rate_2_start)
+        make_notification(eligble_rate_2_end)
+        make_notification(eligble_rate_3_start)
+        make_notification(eligble_rate_3_whenever)
+
+        start = datetime(2016, 1, 1)
+        end = datetime(2018, 1, 1)
+
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(start, end, sample_service.id)[0] == 6
+        assert get_total_billable_units_for_sent_sms_notifications_in_date_range(
+            start, end, sample_service.id
+        )[1] == expected_cost
+    finally:
+        current_app.config['FREE_SMS_TIER_FRAGMENT_COUNT'] = start_value

tests/app/service/test_rest.py

@@ -27,6 +27,7 @@ from app.models import (
 )
 
 from tests.app.db import create_user
+from tests.conftest import set_config_values
 
 
 def test_get_service_list(client, service_factory):
@@ -147,7 +148,32 @@ def test_get_service_by_id(client, sample_service):
     assert json_resp['data']['sms_sender'] == current_app.config['FROM_NUMBER']
 
 
+def test_get_service_by_id_returns_free_sms_limit(client, sample_service):
+
+    auth_header = create_authorization_header()
+    resp = client.get(
+        '/service/{}'.format(sample_service.id),
+        headers=[auth_header]
+    )
+    assert resp.status_code == 200
+    json_resp = json.loads(resp.get_data(as_text=True))
+    assert json_resp['data']['free_sms_fragment_limit'] == 250000
+
+
+def test_get_detailed_service_by_id_returns_free_sms_limit(client, sample_service):
+
+    auth_header = create_authorization_header()
+    resp = client.get(
+        '/service/{}?detailed=True'.format(sample_service.id),
+        headers=[auth_header]
+    )
+    assert resp.status_code == 200
+    json_resp = json.loads(resp.get_data(as_text=True))
+    assert json_resp['data']['free_sms_fragment_limit'] == 250000
+
+
 def test_get_service_list_has_default_permissions(client, service_factory):
+    service_factory.get('one')
     service_factory.get('one')
     service_factory.get('two')
     service_factory.get('three')
@@ -2032,7 +2058,7 @@ def test_get_yearly_billing_usage_count_returns_from_cache_if_present(client, sa
         '/service/{}/yearly-sms-billable-units?year=2016'.format(sample_service.id),
         headers=[create_authorization_header()]
     )
-    print(response.get_data(as_text=True))
+    response.get_data(as_text=True)
     assert response.status_code == 200
     assert json.loads(response.get_data(as_text=True)) == {
         'billable_sms_units': 50,