add signal statistics support per signal

src/dispatch/signal/service.py

@@ -971,9 +971,13 @@ def get_cases_for_signal_by_resolution_reason(
 
 
 def get_signal_stats(
-    *, db_session: Session, entity_value: str, entity_type_id: int, num_days: int | None
+    *, db_session: Session, entity_value: str, entity_type_id: int, signal_id: int | None = None, num_days: int | None = None
 ) -> Optional[SignalStats]:
-    """Gets a signal statistics for a given named entity and type."""
+    """
+    Gets signal statistics for a given named entity and type.
+
+    If signal_id is provided, only returns stats for that specific signal definition.
+    """
     entity_subquery = (
         db_session.query(
             func.jsonb_build_array(
@@ -1027,6 +1031,7 @@ def get_signal_stats(
             and_(
                 Entity.value == entity_value,
                 Entity.entity_type_id == entity_type_id,
+                SignalInstance.signal_id == signal_id if signal_id else True,
                 SignalInstance.created_at >= date_threshold if date_threshold else True,
             )
         )

src/dispatch/signal/views.py

@@ -290,7 +290,7 @@ def return_signal_stats(
     entity_type_id: int = Query(..., description="The ID of the entity type"),
     num_days: int = Query(None, description="The number of days to look back"),
 ):
-    """Gets a signal statistics given a named entity and entity type id."""
+    """Gets signal statistics given a named entity and entity type id."""
     signal_data = get_signal_stats(
         db_session=db_session,
         entity_value=entity_value,
@@ -300,6 +300,32 @@ def return_signal_stats(
     return signal_data
 
 
+@router.get("/{signal_id}/stats", response_model=SignalStats)
+def return_single_signal_stats(
+    db_session: DbSession,
+    signal_id: Union[str, PrimaryKey],
+    entity_value: str = Query(..., description="The name of the entity"),
+    entity_type_id: int = Query(..., description="The ID of the entity type"),
+    num_days: int = Query(None, description="The number of days to look back"),
+):
+    """Gets signal statistics for a specific signal given a named entity and entity type id."""
+    signal = get_by_primary_or_external_id(db_session=db_session, signal_id=signal_id)
+    if not signal:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail=[{"msg": "A signal with this id does not exist."}],
+        )
+
+    signal_data = get_signal_stats(
+        db_session=db_session,
+        entity_value=entity_value,
+        entity_type_id=entity_type_id,
+        signal_id=signal.id,
+        num_days=num_days,
+    )
+    return signal_data
+
+
 @router.get("/{signal_id}", response_model=SignalRead)
 def get_signal(db_session: DbSession, signal_id: Union[str, PrimaryKey]):
     """Gets a signal by its id."""

tests/signal/test_signal_data_service.py → tests/signal/test_signal_stats_service.py

@@ -161,3 +161,78 @@ def test_get_signal_stats_not_found(session, entity_type):
     assert signal_data.num_signal_instances_snoozed == 0
     assert signal_data.num_snoozes_active == 0
     assert signal_data.num_snoozes_expired == 0
+
+
+def test_get_signal_stats_with_signal_id_filter(session, entity, entity_type):
+    """Test get_signal_stats with a specific signal ID filter."""
+    from dispatch.signal.service import get_signal_stats
+    from dispatch.signal.models import Signal, SignalInstance
+
+    # Setup: Create two different signals
+    signal1 = Signal(name="Test Signal 1", variant="test-signal-1", project_id=1)
+    signal2 = Signal(name="Test Signal 2", variant="test-signal-2", project_id=1)
+    session.add_all([signal1, signal2])
+    session.flush()
+
+    # Associate entity with entity type
+    entity.entity_type = entity_type
+
+    # Create a signal instance for signal1
+    signal_instance1 = SignalInstance(signal=signal1, project_id=1)
+    signal_instance1.entities.append(entity)
+
+    # Create two signal instances for signal2
+    signal_instance2 = SignalInstance(signal=signal2, project_id=1)
+    signal_instance2.entities.append(entity)
+    signal_instance3 = SignalInstance(signal=signal2, project_id=1)
+    signal_instance3.entities.append(entity)
+
+    session.add_all([signal_instance1, signal_instance2, signal_instance3])
+    session.commit()
+
+    # Execute: Call the service function without signal_id (should count both signals)
+    signal_data_all = get_signal_stats(
+        db_session=session,
+        entity_value=entity.value,
+        entity_type_id=entity_type.id,
+        num_days=None,
+    )
+
+    # Execute: Call the service function with signal_id for signal1
+    signal_data_signal1 = get_signal_stats(
+        db_session=session,
+        entity_value=entity.value,
+        entity_type_id=entity_type.id,
+        signal_id=signal1.id,
+        num_days=None,
+    )
+
+    # Execute: Call the service function with signal_id for signal2
+    signal_data_signal2 = get_signal_stats(
+        db_session=session,
+        entity_value=entity.value,
+        entity_type_id=entity_type.id,
+        signal_id=signal2.id,
+        num_days=None,
+    )
+
+    # Assert: Without signal_id filter, we should count both instances
+    assert (
+        signal_data_all.num_signal_instances_alerted
+        + signal_data_all.num_signal_instances_snoozed
+        == 3
+    )
+
+    # Assert: With signal1 filter, we should count only signal_instance1
+    assert (
+        signal_data_signal1.num_signal_instances_alerted
+        + signal_data_signal1.num_signal_instances_snoozed
+        == 1
+    )
+
+    # Assert: With signal2 filter, we should count only signal_instance2
+    assert (
+        signal_data_signal2.num_signal_instances_alerted
+        + signal_data_signal2.num_signal_instances_snoozed
+        == 2
+    )