Added new endpoint to get the new template stats

Added a new endpoint which combines the usage of the stats table and the
data from the notifications tables, instead of using all the data from
the notification_history table. This should speed up the query times
and improve the page performance.

- Updated to make the stats create and update function transactional as
it actually wasn't committing the data to the table
- Added the get from the stats table
- Add a a method to combine the two results
- Added the endpoint

app/dao/services_dao.py

@@ -12,31 +12,33 @@ from app.dao.dao_utils import (
 )
 from app.dao.date_util import get_financial_year
 from app.dao.service_sms_sender_dao import insert_service_sms_sender
+from app.dao.stats_template_usage_by_month_dao import dao_get_template_usage_stats_by_service
 from app.models import (
-    ProviderStatistics,
-    VerifyCode,
+    AnnualBilling,
     ApiKey,
+    InboundNumber,
+    InvitedUser,
+    Job,
+    JobStatistics,
+    Notification,
+    NotificationHistory,
+    Permission,
+    ProviderStatistics,
+    Service,
+    ServicePermission,
+    ServiceSmsSender,
+    StatsTemplateUsageByMonth,
     Template,
     TemplateHistory,
     TemplateRedacted,
-    InboundNumber,
-    Job,
-    NotificationHistory,
-    Notification,
-    Permission,
     User,
-    InvitedUser,
-    Service,
-    ServicePermission,
-    KEY_TYPE_TEST,
-    NOTIFICATION_STATUS_TYPES,
-    TEMPLATE_TYPES,
-    JobStatistics,
-    SMS_TYPE,
+    VerifyCode,
     EMAIL_TYPE,
     INTERNATIONAL_SMS_TYPE,
-    ServiceSmsSender,
-    AnnualBilling
+    KEY_TYPE_TEST,
+    NOTIFICATION_STATUS_TYPES,
+    SMS_TYPE,
+    TEMPLATE_TYPES
 )
 from app.service.statistics import format_monthly_template_notification_stats
 from app.statsd_decorators import statsd
@@ -540,5 +542,61 @@ def dao_fetch_monthly_historical_stats_by_template():
         month,
         year
     ).order_by(
-        NotificationHistory.template_id
+        year,
+        month
     ).all()
+
+
+@transactional
+@statsd(namespace="dao")
+def dao_fetch_monthly_historical_usage_by_template_for_service(service_id):
+
+    results = dao_get_template_usage_stats_by_service(service_id)
+
+    stats = list()
+    for result in results:
+        stat = StatsTemplateUsageByMonth(
+            template_id=result.template_id,
+            month=result.month,
+            year=result.year,
+            count=result.count
+        )
+        stats.append(stat)
+
+    month = get_london_month_from_utc_column(Notification.created_at)
+    year = func.date_trunc("year", Notification.created_at)
+    start_date = datetime.combine(date.today(), time.min)
+
+    today_results = db.session.query(
+        Notification.template_id,
+        extract('month', month).label('month'),
+        extract('year', year).label('year'),
+        func.count().label('count')
+    ).filter(
+        Notification.created_at >= start_date
+    ).group_by(
+        Notification.template_id,
+        month,
+        year
+    ).order_by(
+        Notification.template_id
+    ).all()
+
+    for today_result in today_results:
+        add_to_stats = True
+        for stat in stats:
+            if today_result.template_id == stat.template_id:
+                stat.count = stat.count + today_result.count
+                add_to_stats = False
+
+        if add_to_stats:
+            new_stat = StatsTemplateUsageByMonth(
+                template_id=today_result.template_id,
+                month=today_result.month,
+                year=today_result.year,
+                count=today_result.count
+            )
+
+            stats.append(new_stat)
+
+    return stats

app/dao/stats_template_usage_by_month_dao.py

@@ -1,7 +1,11 @@
 from app import db
-from app.models import StatsTemplateUsageByMonth
+from app.statsd_decorators import statsd
+from app.dao.dao_utils import transactional
+from app.models import StatsTemplateUsageByMonth, Template
 
 
+@transactional
+@statsd(namespace="dao")
 def insert_or_update_stats_for_template(template_id, month, year, count):
     result = db.session.query(
         StatsTemplateUsageByMonth
@@ -21,4 +25,16 @@ def insert_or_update_stats_for_template(template_id, month, year, count):
             year=year,
             count=count
         )
+
         db.session.add(monthly_stats)
+
+
+@statsd(namespace="dao")
+def dao_get_template_usage_stats_by_service(service_id):
+    return db.session.query(
+        StatsTemplateUsageByMonth
+    ).join(
+        Template, StatsTemplateUsageByMonth.template_id == Template.id
+    ).filter(
+        Template.service_id == service_id
+    ).all()