refactor: remove tracer dependencies to support dsm sqs -> lambda

datadog_lambda/dsm.py

@@ -1,38 +1,69 @@
-from datadog_lambda import logger
+import logging
+import json
 from datadog_lambda.trigger import EventTypes
 
+logger = logging.getLogger(__name__)
 
-def set_dsm_context(event, event_source):
 
+def set_dsm_context(event, event_source):
     if event_source.equals(EventTypes.SQS):
         _dsm_set_sqs_context(event)
 
 
 def _dsm_set_sqs_context(event):
-    from datadog_lambda.wrapper import format_err_with_traceback
-    from ddtrace.internal.datastreams import data_streams_processor
-    from ddtrace.internal.datastreams.processor import DsmPathwayCodec
-    from ddtrace.internal.datastreams.botocore import (
-        get_datastreams_context,
-        calculate_sqs_payload_size,
-    )
-
     records = event.get("Records")
     if records is None:
         return
-    processor = data_streams_processor()
 
     for record in records:
+        arn = record.get("eventSourceARN", "")
         try:
-            queue_arn = record.get("eventSourceARN", "")
-
-            contextjson = get_datastreams_context(record)
-            payload_size = calculate_sqs_payload_size(record)
+            context_json = _get_dsm_context_from_sqs_lambda(record)
+            if not context_json:
+                return
+            _set_dsm_context_for_record(context_json, "sqs", arn)
 
-            ctx = DsmPathwayCodec.decode(contextjson, processor)
-            ctx.set_checkpoint(
-                ["direction:in", f"topic:{queue_arn}", "type:sqs"],
-                payload_size=payload_size,
-            )
         except Exception as e:
-            logger.error(format_err_with_traceback(e))
+            logger.error(f"Unable to set dsm context: {e}")
+
+
+def _set_dsm_context_for_record(context_json, type, arn):
+    from ddtrace.data_streams import set_consume_checkpoint
+
+    carrier_get = _create_carrier_get(context_json)
+    set_consume_checkpoint(type, arn, carrier_get, manual_checkpoint=False)
+
+
+def _get_dsm_context_from_sqs_lambda(message):
+    """
+    Lambda-specific message shape for SQS -> Lambda:
+        - message.messageAttributes._datadog.stringValue
+    """
+    context_json = None
+    message_attributes = message.get("messageAttributes")
+    if not message_attributes:
+        logger.debug("DataStreams skipped lambda message: %r", message)
+        return None
+
+    if "_datadog" not in message_attributes:
+        logger.debug("DataStreams skipped lambda message: %r", message)
+        return None
+
+    datadog_attr = message_attributes["_datadog"]
+
+    if "stringValue" in datadog_attr:
+        context_json = json.loads(datadog_attr["stringValue"])
+        if not isinstance(context_json, dict):
+            logger.debug("DataStreams did not handle lambda message: %r", message)
+            return None
+    else:
+        logger.debug("DataStreams did not handle lambda message: %r", message)
+
+    return context_json
+
+
+def _create_carrier_get(context_json):
+    def carrier_get(key):
+        return context_json.get(key)
+
+    return carrier_get