fix(nimbus): use StrEnum for string conversion (#9933)

Because

- #9921 broke analysis results ingestion by including the enum member in
the string path to results instead of the enum value
- the fix was obvious enough that it was worth fixing instead of
reverting

This commit

- uses `StrEnum` as the base class for enums in
`experimenter.jetstream.models`

Fixes #9932

experimenter/experimenter/jetstream/models.py

@@ -1,4 +1,4 @@
-from enum import Enum
+from enum import StrEnum
 from typing import Any
 
 from mozilla_nimbus_schemas.jetstream import AnalysisBasis
@@ -8,32 +8,32 @@ from pydantic import BaseModel, create_model
 from experimenter.experiments.models import NimbusExperiment
 
 
-class AnalysisWindow(str, Enum):
+class AnalysisWindow(StrEnum):
     DAILY = "daily"
     WEEKLY = "weekly"
     OVERALL = "overall"
 
 
-class Significance(str, Enum):
+class Significance(StrEnum):
     POSITIVE = "positive"
     NEGATIVE = "negative"
     NEUTRAL = "neutral"
 
 
-class BranchComparison(str, Enum):
+class BranchComparison(StrEnum):
     ABSOLUTE = "absolute"
     DIFFERENCE = "difference"
     UPLIFT = "relative_uplift"
 
 
-class Metric(str, Enum):
+class Metric(StrEnum):
     RETENTION = "retained"
     SEARCH = "search_count"
     DAYS_OF_USE = "days_of_use"
     USER_COUNT = "identity"
 
 
-class Statistic(str, Enum):
+class Statistic(StrEnum):
     """
     This is the list of statistics supported in Experimenter,
     not a complete list of statistics available in Jetstream.
@@ -45,13 +45,13 @@ class Statistic(str, Enum):
     COUNT = "count"
 
 
-class Segment(str, Enum):
+class Segment(StrEnum):
     ALL = "all"
 
 
 # TODO: Consider a "guardrail_metrics" group containing "days_of_use",
 # "retained", and "search_count".
-class Group(str, Enum):
+class Group(StrEnum):
     SEARCH = "search_metrics"
     USAGE = "usage_metrics"
     OTHER = "other_metrics"

experimenter/experimenter/jetstream/tests/test_tasks.py

@@ -10,7 +10,8 @@ from parameterized import parameterized
 from experimenter.experiments.models import NimbusExperiment
 from experimenter.experiments.tests.factories import NimbusExperimentFactory
 from experimenter.jetstream import tasks
-from experimenter.jetstream.models import Group
+from experimenter.jetstream.client import get_data
+from experimenter.jetstream.models import AnalysisWindow, Group
 from experimenter.jetstream.tests import mock_valid_outcomes
 from experimenter.jetstream.tests.constants import (
     JetstreamTestData,
@@ -1113,6 +1114,28 @@ class TestFetchJetstreamDataTask(MockSizingDataMixin, TestCase):
         with self.assertRaises(Exception):
             tasks.fetch_experiment_data(experiment.id)
 
+    @patch("experimenter.jetstream.client.validate_data")
+    @patch("experimenter.jetstream.client.load_data_from_gcs")
+    def test_builds_statistics_filename(
+        self, mock_load_data_from_gcs, mock_validate_data
+    ):
+        lifecycle = NimbusExperimentFactory.Lifecycles.ENDING_APPROVE_APPROVE
+        offset = NimbusExperiment.DAYS_ANALYSIS_BUFFER + 1
+        experiment = NimbusExperimentFactory.create_with_lifecycle(
+            lifecycle, end_date=datetime.date.today() - datetime.timedelta(days=offset)
+        )
+
+        mock_validate_data.return_value = True
+
+        recipe_slug = experiment.slug.replace("-", "_")
+        window = AnalysisWindow.OVERALL
+        get_data(recipe_slug, AnalysisWindow.OVERALL)
+        filename = f"statistics/statistics_{recipe_slug}_{window}.json"
+        mock_load_data_from_gcs.assert_called_with(filename)
+
+        assert "AnalysisWindow" not in filename
+        assert "overall" in filename
+
     @patch("django.core.files.storage.default_storage.open")
     @patch("django.core.files.storage.default_storage.exists")
     def test_sizing_data_parsed_and_stored(self, mock_exists, mock_open):