feat: disable direct metric submission in govcloud

Author: apiarian-datadog

datadog_lambda/api.py

@@ -1,6 +1,8 @@
 import os
 import logging
 
+from datadog_lambda.aws import current_region, running_in_gov_region
+
 logger = logging.getLogger(__name__)
 KMS_ENCRYPTION_CONTEXT_KEY = "LambdaFunctionName"
 api_key = None
@@ -62,9 +64,9 @@ def get_api_key() -> str:
     DD_KMS_API_KEY = os.environ.get("DD_KMS_API_KEY", "")
     DD_API_KEY = os.environ.get("DD_API_KEY", os.environ.get("DATADOG_API_KEY", ""))
 
-    LAMBDA_REGION = os.environ.get("AWS_REGION", "")
-    is_gov_region = LAMBDA_REGION.startswith("us-gov-")
-    if is_gov_region:
+    LAMBDA_REGION = current_region()
+    is_gov_region = running_in_gov_region()
+    if is_gov_region():
         logger.debug(
             "Govcloud region detected. Using FIPs endpoints for secrets management."
         )

datadog_lambda/aws.py

@@ -0,0 +1,9 @@
+import os
+
+
+def current_region() -> str:
+    return os.environ.get("AWS_REGION", "")
+
+
+def running_in_gov_region() -> bool:
+    return current_region().startswith("us-gov-")

datadog_lambda/metric.py

@@ -11,6 +11,7 @@
 
 from datadog_lambda.extension import should_use_extension
 from datadog_lambda.tags import get_enhanced_metrics_tags, dd_lambda_layer_tag
+from datadog_lambda.aws import running_in_gov_region
 
 logger = logging.getLogger(__name__)
 
@@ -76,6 +77,17 @@ def lambda_metric(metric_name, value, timestamp=None, tags=None, force_async=Fal
     tags.append(dd_lambda_layer_tag)
 
     if should_use_extension and timestamp is not None:
+        if running_in_gov_region():
+            # Metrics with timestamps get shipped directly to datadog instead
+            # of going to the agent. We cannot guarantee from our side that
+            # this will be done in a FIPS-compliant way, so we disable this
+            # feature for now. We may revisit it in the future.
+            logger.warning(
+                "Ignoring metric submission for metric '%s' because we cannot guarantee FIPS-compliance for metrics submitted directly to Datadog.",
+                metric_name,
+            )
+            return
+
         # The extension does not support timestamps for distributions so we create a
         # a thread stats writer to submit metrics with timestamps to the API
         timestamp_ceiling = int(