add Requests method for counting all requests with a given status

atst/domain/requests.py

@@ -1,4 +1,6 @@
+from enum import Enum
 from sqlalchemy import exists, and_, exc
+from sqlalchemy.sql import text
 from sqlalchemy.orm.exc import NoResultFound
 from sqlalchemy.orm.attributes import flag_modified
 
@@ -154,3 +156,21 @@ class Requests(object):
     @classmethod
     def is_pending_ccpo_approval(cls, request):
         return request.status == RequestStatus.PENDING_CCPO_APPROVAL
+
+    @classmethod
+    def count_status(self, status):
+        raw = text("""
+SELECT count(requests_with_status.id)
+FROM (
+    SELECT DISTINCT ON (rse.request_id) r.*, rse.new_status as status
+    FROM request_status_events rse JOIN requests r ON r.id = rse.request_id
+    ORDER BY rse.request_id, rse.sequence DESC
+) as requests_with_status
+WHERE requests_with_status.status = :status;
+        """)
+        if isinstance(status, Enum):
+            status = status.name
+        results = db.session.execute(raw, {"status": status}).fetchone()
+        (count,) = results
+        return count
+

tests/conftest.py

@@ -69,6 +69,7 @@ def session(db, request):
     ]
     for factory in factory_list:
         factory._meta.sqlalchemy_session = session
+        factory._meta.sqlalchemy_session_persistence = "commit"
 
     yield session
 

tests/domain/test_requests.py

@@ -3,9 +3,10 @@ from uuid import uuid4
 
 from atst.domain.exceptions import NotFoundError
 from atst.domain.requests import Requests
+from atst.models.request import Request
 from atst.models.request_status_event import RequestStatus
 
-from tests.factories import RequestFactory, UserFactory
+from tests.factories import RequestFactory, UserFactory, RequestStatusEventFactory
 
 
 @pytest.fixture(scope="function")
@@ -63,3 +64,15 @@ def test_exists(session):
     request = RequestFactory.create(creator=user_allowed)
     assert Requests.exists(request.id, user_allowed)
     assert not Requests.exists(request.id, user_denied)
+
+
+def test_count_status(session):
+    # make sure table is empty
+    session.query(Request).delete()
+
+    request1 = RequestFactory.create()
+    request2 = RequestFactory.create()
+    RequestStatusEventFactory.create(sequence=2, request_id=request2.id, new_status=RequestStatus.PENDING_FINANCIAL_VERIFICATION)
+
+    assert Requests.count_status(RequestStatus.PENDING_FINANCIAL_VERIFICATION) == 1
+    assert Requests.count_status(RequestStatus.STARTED) == 1

tests/factories.py

@@ -39,6 +39,7 @@ class RequestStatusEventFactory(factory.alchemy.SQLAlchemyModelFactory):
         model = RequestStatusEvent
 
     id = factory.Sequence(lambda x: uuid4())
+    sequence = 1
 
 
 class RequestFactory(factory.alchemy.SQLAlchemyModelFactory):