fix: timestamps we send to the extension should be integers (#590)

Also added some defense in depth for our lower level statsd call.

Author: apiarian-datadog

datadog_lambda/dogstatsd.py

@@ -97,7 +97,7 @@ def _serialize_metric(self, metric, metric_type, value, tags, timestamp):
             value,
             metric_type,
             ("|#" + ",".join(self.normalize_tags(tags))) if tags else "",
-            ("|T" + str(timestamp)) if timestamp is not None else "",
+            ("|T" + str(int(timestamp))) if timestamp is not None else "",
         )
 
     def _report(self, metric, metric_type, value, tags, timestamp):

datadog_lambda/metric.py

@@ -111,6 +111,18 @@ def lambda_metric(metric_name, value, timestamp=None, tags=None, force_async=Fal
             if isinstance(timestamp, datetime):
                 timestamp = int(timestamp.timestamp())
 
+            else:
+                try:
+                    timestamp = int(timestamp)
+                except Exception:
+                    logger.debug(
+                        "Ignoring metric submission for metric '%s' because the timestamp cannot "
+                        "be turned into an integer: %r",
+                        metric_name,
+                        timestamp,
+                    )
+                    return
+
             timestamp_floor = int((datetime.now() - timedelta(hours=4)).timestamp())
             if timestamp < timestamp_floor:
                 logger.warning(

tests/test_dogstatsd.py

@@ -53,3 +53,7 @@ def test_distribution_with_tags(self):
     def test_distribution_with_timestamp(self):
         statsd.distribution("my.test.timestamp.metric", 9, timestamp=123456789)
         self._checkOnlyOneMetric("my.test.timestamp.metric:9|d|T123456789")
+
+    def test_distribution_with_float_timestamp(self):
+        statsd.distribution("my.test.timestamp.metric", 9, timestamp=123456789.123)
+        self._checkOnlyOneMetric("my.test.timestamp.metric:9|d|T123456789")

tests/test_metric.py

@@ -111,6 +111,34 @@ def test_lambda_metric_datetime_with_extension(self):
         )
         self.mock_write_metric_point_to_stdout.assert_not_called()
 
+    @patch("datadog_lambda.metric.metrics_handler", MetricsHandler.EXTENSION)
+    def test_lambda_metric_float_with_extension(self):
+        delta = timedelta(minutes=1)
+        timestamp_float = (datetime.now() - delta).timestamp()
+        timestamp_int = int(timestamp_float)
+
+        lambda_metric("test_timestamp", 1, timestamp_float)
+        self.mock_metric_lambda_stats.distribution.assert_has_calls(
+            [
+                call(
+                    "test_timestamp",
+                    1,
+                    timestamp=timestamp_int,
+                    tags=[dd_lambda_layer_tag],
+                )
+            ]
+        )
+        self.mock_write_metric_point_to_stdout.assert_not_called()
+
+    @patch("datadog_lambda.metric.metrics_handler", MetricsHandler.EXTENSION)
+    def test_lambda_metric_timestamp_junk_with_extension(self):
+        delta = timedelta(minutes=1)
+        timestamp = (datetime.now() - delta).isoformat()
+
+        lambda_metric("test_timestamp", 1, timestamp)
+        self.mock_metric_lambda_stats.distribution.assert_not_called()
+        self.mock_write_metric_point_to_stdout.assert_not_called()
+
     @patch("datadog_lambda.metric.metrics_handler", MetricsHandler.EXTENSION)
     def test_lambda_metric_invalid_timestamp_with_extension(self):
         delta = timedelta(hours=5)