Fail freshness if variable is missing. (sodadata#1304)

* Fail freshness if variable is missing.

Fix sodadata#1200

Co-authored-by: Vijay Kiran <mail@vijaykiran.com>

soda/core/soda/execution/freshness_check.py

@@ -46,6 +46,14 @@ def evaluate(self, metrics: Dict[str, Metric], historic_values: Dict[str, object
         check_cfg: FreshnessCheckCfg = self.check_cfg
 
         now_variable_name = check_cfg.variable_name
+        now_variable_timestamp_text = self.data_source_scan.scan.get_variable(now_variable_name)
+        if not now_variable_timestamp_text:
+            self.outcome = CheckOutcome.FAIL
+            self.logs.error(
+                f"Could not parse variable {now_variable_name} as a timestamp: variable not found",
+            )
+            return
+
         max_column_timestamp: Optional[datetime] = metrics.get(MAX_COLUMN_TIMESTAMP).value
         now_variable_timestamp: Optional[datetime] = None
 
@@ -57,19 +65,13 @@ def evaluate(self, metrics: Dict[str, Metric], historic_values: Dict[str, object
                 location=self.check_cfg.location,
             )
 
-        now_variable_timestamp_text = self.data_source_scan.scan.get_variable(now_variable_name)
-        if now_variable_timestamp_text is not None:
-            try:
-                now_variable_timestamp = datetime.fromisoformat(now_variable_timestamp_text)
-            except:
-                self.logs.error(
-                    f"Could not parse variable {now_variable_name} as a timestamp: {now_variable_timestamp_text}",
-                    location=check_cfg.location,
-                )
-        else:
-            now_variable_timestamp = self.data_source_scan.scan._data_timestamp
-            now_variable_name = "scan._scan_time"
-            now_variable_timestamp_text = str(now_variable_timestamp)
+        try:
+            now_variable_timestamp = datetime.fromisoformat(now_variable_timestamp_text)
+        except:
+            self.logs.error(
+                f"Could not parse variable {now_variable_name} as a timestamp: {now_variable_timestamp_text}",
+                location=check_cfg.location,
+            )
 
         is_now_variable_timestamp_valid = isinstance(now_variable_timestamp, datetime)
 

soda/core/tests/data_source/test_freshness.py

@@ -22,7 +22,7 @@ def test_freshness_timezones_input_no_tz(scanner: Scanner):
     table_name = scanner.ensure_test_table(customers_test_table)
 
     scan = scanner.create_test_scan()
-    scan.add_variables({"NOW": "2020-06-25 00:00:00"})
+    scan.add_variables({"NOW": "2020-06-25 00:00:00"})  # NOW overrides default "now" variable in scan.
     scan.add_sodacl_yaml_str(
         f"""
       checks for {table_name}:
@@ -39,7 +39,7 @@ def test_freshness_timezones_input_with_tz(scanner: Scanner):
     table_name = scanner.ensure_test_table(customers_test_table)
 
     scan = scanner.create_test_scan()
-    scan.add_variables({"NOW": "2020-06-25 01:00:00+01:00"})
+    scan.add_variables({"NOW": "2020-06-25 01:00:00+01:00"})  # NOW overrides default "now" variable in scan.
     scan.add_sodacl_yaml_str(
         f"""
       checks for {table_name}:
@@ -90,7 +90,7 @@ def test_freshness_warning(scanner: Scanner):
     table_name = scanner.ensure_test_table(customers_test_table)
 
     scan = scanner.create_test_scan()
-    scan.add_variables({"NOW": "2020-06-25 00:00:00"})
+    scan.add_variables({"NOW": "2020-06-25 00:00:00"})  # NOW overrides default "now" variable in scan.
     scan.add_sodacl_yaml_str(
         f"""
       checks for {table_name}:
@@ -150,3 +150,19 @@ def test_freshness_no_rows(scanner: Scanner):
     scan.execute()
 
     scan.assert_all_checks_fail()
+
+
+def test_fail_freshness_var_missing(scanner: Scanner):
+    table_name = scanner.ensure_test_table(customers_test_table)
+
+    scan = scanner.create_test_scan()
+    scan.add_sodacl_yaml_str(
+        f"""
+      checks for {table_name}:
+        - freshness using ts with CUSTOM_USER_VAR < 1d
+    """
+    )
+    scan.execute(allow_error_warning=True)
+
+    scan.assert_all_checks_fail()
+    scan.assert_log_error("variable not found")

soda/core/tests/helpers/scanner.py

@@ -71,9 +71,11 @@ def enable_mock_soda_cloud(self) -> MockSodaCloud:
             self._configuration.soda_cloud = MockSodaCloud()
         return self._configuration.soda_cloud
 
-    def execute(self):
+    def execute(self, allow_error_warning: bool = False):
         super().execute()
-        self.assert_no_error_nor_warning_logs()
+
+        if not allow_error_warning:
+            self.assert_no_error_nor_warning_logs()
 
     def execute_unchecked(self):
         super().execute()