make sure we convert strings to dates before we use them

fixes 500 on platform admin page

app/service/rest.py

@@ -66,9 +66,12 @@ def get_services():
     detailed = request.args.get('detailed') == 'True'
     user_id = request.args.get('user_id', None)
     include_from_test_key = request.args.get('include_from_test_key', 'True') != 'False'
+
     # If start and end date are not set, we are expecting today's stats.
-    start_date = request.args.get('start_date', datetime.utcnow().date())
-    end_date = request.args.get('end_date', datetime.utcnow().date())
+    today = str(datetime.utcnow().date())
+
+    start_date = datetime.strptime(request.args.get('start_date', today), '%Y-%m-%d').date()
+    end_date = datetime.strptime(request.args.get('end_date', today), '%Y-%m-%d').date()
 
     if user_id:
         services = dao_fetch_all_services_by_user(user_id, only_active)

tests/app/service/test_rest.py

@@ -1,6 +1,7 @@
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, date
 import json
 import uuid
+from unittest.mock import ANY
 
 import pytest
 from flask import url_for
@@ -1269,6 +1270,39 @@ def test_get_services_with_detailed_flag_excluding_from_test_key(notify_api, not
     }
 
 
+def test_get_services_with_detailed_flag_accepts_date_range(client, mocker):
+    mock_get_detailed_services = mocker.patch('app.service.rest.get_detailed_services', return_value={})
+    resp = client.get(
+        url_for('service.get_services', detailed=True, start_date='2001-01-01', end_date='2002-02-02'),
+        headers=[create_authorization_header()]
+    )
+
+    mock_get_detailed_services.assert_called_once_with(
+        start_date=date(2001, 1, 1),
+        end_date=date(2002, 2, 2),
+        only_active=ANY,
+        include_from_test_key=ANY
+    )
+    assert resp.status_code == 200
+
+
+@freeze_time('2002-02-02')
+def test_get_services_with_detailed_flag_defaults_to_today(client, mocker):
+    mock_get_detailed_services = mocker.patch('app.service.rest.get_detailed_services', return_value={})
+    resp = client.get(
+        url_for('service.get_services', detailed=True),
+        headers=[create_authorization_header()]
+    )
+
+    mock_get_detailed_services.assert_called_once_with(
+        start_date=date(2002, 2, 2),
+        end_date=date(2002, 2, 2),
+        only_active=ANY,
+        include_from_test_key=ANY
+    )
+    assert resp.status_code == 200
+
+
 def test_get_detailed_services_groups_by_service(notify_db, notify_db_session):
     from app.service.rest import get_detailed_services