MINOR: PBI dataset expressions empty value fix (#21409)

(cherry picked from commit 8bbc4d8c3d7792d0d36a163f119efdccf61840e5)

ingestion/src/metadata/ingestion/source/dashboard/powerbi/metadata.py

@@ -706,6 +706,12 @@ class PowerbiSource(DashboardServiceSource):
                 if dataset and dataset.expressions:
                     # find keyword from dataset expressions
                     for dexpression in dataset.expressions:
+                        if not dexpression.expression:
+                            logger.debug(
+                                f"No expression value found inside dataset"
+                                f"({dataset.name}) expressions' name={dexpression.name}"
+                            )
+                            continue
                         if dexpression.name == match.group(2):
                             pattern = r'DefaultValue="([^"]+)"'
                             kw_match = re.search(pattern, dexpression.expression)
@@ -784,7 +790,9 @@ class PowerbiSource(DashboardServiceSource):
             if not isinstance(table.source, list):
                 return {}
             source_expression = table.source[0].expression
-
+            if not source_expression:
+                logger.debug(f"No source expression found for table: {table.name}")
+                return {}
             # parse snowflake source
             table_info = self._parse_snowflake_source(
                 source_expression, datamodel_entity

ingestion/src/metadata/ingestion/source/dashboard/powerbi/models.py

@@ -143,7 +143,7 @@ class PowerBITableSource(BaseModel):
     PowerBI Table Source
     """
 
-    expression: str
+    expression: Optional[str] = None
 
 
 class PowerBiTable(BaseModel):
@@ -171,7 +171,7 @@ class TablesResponse(BaseModel):
 
 class DatasetExpression(BaseModel):
     name: str
-    expression: str
+    expression: Optional[str] = None
 
 
 class Dataset(BaseModel):

ingestion/tests/unit/topology/dashboard/test_powerbi.py

@@ -15,7 +15,12 @@ from metadata.generated.schema.type.entityReference import EntityReference
 from metadata.generated.schema.type.entityReferenceList import EntityReferenceList
 from metadata.ingestion.ometa.ometa_api import OpenMetadata
 from metadata.ingestion.source.dashboard.powerbi.metadata import PowerbiSource
-from metadata.ingestion.source.dashboard.powerbi.models import Dataset, PowerBIDashboard
+from metadata.ingestion.source.dashboard.powerbi.models import (
+    Dataset,
+    PowerBIDashboard,
+    PowerBiTable,
+    PowerBITableSource,
+)
 
 MOCK_REDSHIFT_EXP = """
 let
@@ -167,6 +172,19 @@ MOCK_DATASET_FROM_WORKSPACE = Dataset(
         },
     ],
 )
+MOCK_DATASET_FROM_WORKSPACE_V2 = Dataset(
+    id="testdataset",
+    name="Test Dataset",
+    tables=[],
+    expressions=[
+        {
+            "name": "DB",
+        },
+        {
+            "name": "Schema",
+        },
+    ],
+)
 MOCK_DASHBOARD_DATA_MODEL = DashboardDataModel(
     name="dummy_datamodel",
     id=uuid.uuid4(),
@@ -292,3 +310,50 @@ class PowerBIUnitTest(TestCase):
 
         # Verify get_reference_by_email was not called when there are no owners
         self.powerbi.metadata.get_reference_by_email.assert_not_called()
+
+    @pytest.mark.order(3)
+    def test_parse_table_info_from_source_exp(self):
+        table = PowerBiTable(
+            name="test_table",
+            source=[PowerBITableSource(expression=MOCK_REDSHIFT_EXP)],
+        )
+        result = self.powerbi._parse_table_info_from_source_exp(
+            table, MOCK_DASHBOARD_DATA_MODEL
+        )
+        self.assertEqual(result, EXPECTED_REDSHIFT_RESULT)
+
+        # no source expression
+        table = PowerBiTable(
+            name="test_table",
+            source=[PowerBITableSource(expression=None)],
+        )
+        result = self.powerbi._parse_table_info_from_source_exp(
+            table, MOCK_DASHBOARD_DATA_MODEL
+        )
+        self.assertEqual(result, {})
+
+        # no source
+        table = PowerBiTable(
+            name="test_table",
+            source=[],
+        )
+        result = self.powerbi._parse_table_info_from_source_exp(
+            table, MOCK_DASHBOARD_DATA_MODEL
+        )
+        self.assertEqual(result, {})
+
+    @pytest.mark.order(4)
+    @patch.object(
+        PowerbiSource,
+        "_fetch_dataset_from_workspace",
+        return_value=MOCK_DATASET_FROM_WORKSPACE_V2,
+    )
+    def test_parse_dataset_expressions(self, *_):
+        # test with valid snowflake source but no
+        # dataset expression value
+        result = self.powerbi._parse_snowflake_source(
+            MOCK_SNOWFLAKE_EXP_V2, MOCK_DASHBOARD_DATA_MODEL
+        )
+        self.assertIsNone(result["database"])
+        self.assertIsNone(result["schema"])
+        self.assertEqual(result["table"], "CUSTOMER_TABLE")