feat(nimbus): Integrate segment retrieval function from metric-config…

…-parser

Because

* experimenter was manually parsing segments when it could just import them from metric-config-parser

This commit

* replaces manual segment parsing with metric-config-parser’s retrieval function

Fixes #11623

experimenter/experimenter/segments/__init__.py

@@ -1,6 +1,8 @@
 from dataclasses import dataclass
 
+from django.core.checks import Error, register
 from metric_config_parser.config import ConfigCollection
+from metric_config_parser.segment import SegmentDefinition
 
 from experimenter.experiments.constants import NimbusConstants
 
@@ -44,15 +46,20 @@ def _load_segments(cls, segment_data=None):
                 app_segments = segment_data.get(app_name, [])
 
             for segment in app_segments:
-                segments.append(
-                    Segment(
-                        slug=segment.name,
-                        friendly_name=segment.friendly_name,
-                        application=app_config.slug,
-                        description=segment.description,
-                        select_expression=segment.select_expression,
+                if isinstance(segment, SegmentDefinition):
+                    segments.append(
+                        Segment(
+                            slug=segment.name,
+                            friendly_name=segment.friendly_name,
+                            application=app_config.slug,
+                            description=segment.description,
+                            select_expression=segment.select_expression,
+                        )
+                    )
+                else:
+                    raise TypeError(
+                        f"Expected SegmentDefinition, got {type(segment).__name__}"
                     )
-                )
 
         return segments
 
@@ -69,3 +76,14 @@ def all(cls, segment_data=None):
     @classmethod
     def by_application(cls, application, segment_data=None):
         return [o for o in cls.all(segment_data) if o.application == application]
+
+
+@register()
+def check_segments(app_configs, segments_data=None, **kwargs):
+    errors = []
+
+    try:
+        Segments.all(segment_data=segments_data)
+    except Exception as e:
+        errors.append(Error(f"Error loading Segments: {e}"))
+    return errors

experimenter/experimenter/segments/tests/__init__.py

@@ -36,3 +36,7 @@ def mock_get_segments():
             ),
         ],
     }
+
+
+def mock_get_invalid_segments():
+    return {"fenix": [{"test": "test_segment"}]}

experimenter/experimenter/segments/tests/test_segments.py

@@ -1,8 +1,9 @@
+from django.core.checks import Error
 from django.test import TestCase
 
 from experimenter.experiments.models import NimbusExperiment
-from experimenter.segments import Segment, Segments
-from experimenter.segments.tests import mock_get_segments
+from experimenter.segments import Segment, Segments, check_segments
+from experimenter.segments.tests import mock_get_invalid_segments, mock_get_segments
 
 
 class TestSegments(TestCase):
@@ -109,3 +110,21 @@ def test_load_segments_by_application(self):
             ),
             desktop_segments,
         )
+
+
+class TestCheckSegments(TestCase):
+    def setUp(self):
+        Segments.clear_cache()
+
+    def test_valid_segments_do_not_trigger_check_error(self):
+        errors = check_segments(app_configs=None, segments_data=mock_get_segments())
+        self.assertEqual(errors, [])
+
+    def test_invalid_segments_trigger_check_error(self):
+        errors = check_segments(
+            app_configs=None, segments_data=mock_get_invalid_segments()
+        )
+        self.assertEqual(
+            errors,
+            [Error(msg="Error loading Segments: Expected SegmentDefinition, got dict")],
+        )