Improve recorded detail of stacktraces

aws_xray_sdk/core/async_recorder.py

@@ -1,9 +1,9 @@
 import time
-import traceback
 
 import wrapt
 
 from aws_xray_sdk.core.recorder import AWSXRayRecorder
+from aws_xray_sdk.core.utils import stacktrace
 
 
 class AsyncAWSXRayRecorder(AWSXRayRecorder):
@@ -47,7 +47,7 @@ async def record_subsegment_async(self, wrapped, instance, args, kwargs, name,
             return return_value
         except Exception as e:
             exception = e
-            stack = traceback.extract_stack(limit=self._max_trace_back)
+            stack = stacktrace.get_stacktrace(limit=self._max_trace_back)
             raise
         finally:
             # No-op if subsegment is `None` due to `LOG_ERROR`.

aws_xray_sdk/core/recorder.py

@@ -4,7 +4,6 @@
 import os
 import platform
 import time
-import traceback
 
 import wrapt
 
@@ -23,6 +22,7 @@
 from .lambda_launcher import check_in_lambda
 from .exceptions.exceptions import SegmentNameMissingException
 from .utils.compat import string_types
+from .utils import stacktrace
 
 log = logging.getLogger(__name__)
 
@@ -398,7 +398,7 @@ def record_subsegment(self, wrapped, instance, args, kwargs, name,
             return return_value
         except Exception as e:
             exception = e
-            stack = traceback.extract_stack(limit=self.max_trace_back)
+            stack = stacktrace.get_stacktrace(limit=self.max_trace_back)
             raise
         finally:
             # No-op if subsegment is `None` due to `LOG_ERROR`.

aws_xray_sdk/core/utils/stacktrace.py

@@ -0,0 +1,51 @@
+import sys
+import traceback
+
+
+def get_stacktrace(limit=None):
+    """
+    Get a full stacktrace for the current state of execution.
+
+    Include the current state of the stack, minus this function.
+    If there is an active exception, include the stacktrace information from
+    the exception as well.
+
+    :param int limit:
+        Optionally limit stack trace size results. This parmaeters has the same
+        meaning as the `limit` parameter in `traceback.print_stack`.
+    :returns:
+        List of stack trace objects, in the same form as
+        `traceback.extract_stack`.
+    """
+    if limit is not None and limit == 0:
+        # Nothing to return. This is consistent with the behavior of the
+        # functions in the `traceback` module.
+        return []
+
+    stack = traceback.extract_stack()
+    # Remove this `get_stacktrace()` function call from the stack info.
+    # For what we want to report, this is superfluous information and arguably
+    # adds garbage to the report.
+    # Also drop the `traceback.extract_stack()` call above from the returned
+    # stack info, since this is also superfluous.
+    stack = stack[:-2]
+
+    _exc_type, _exc, exc_traceback = sys.exc_info()
+    if exc_traceback is not None:
+        # If and only if there is a currently triggered exception, combine the
+        # exception traceback information with the current stack state to get a
+        # complete trace.
+        exc_stack = traceback.extract_tb(exc_traceback)
+        stack += exc_stack
+
+    # Limit the stack trace size, if a limit was specified:
+    if limit is not None:
+        # Copy the behavior of `traceback` functions with a `limit` argument.
+        # See https://docs.python.org/3/library/traceback.html.
+        if limit > 0:
+            # limit > 0: include the last `limit` items
+            stack = stack[-limit:]
+        else:
+            # limit < 0: include the first `abs(limit)` items
+            stack = stack[:abs(limit)]
+    return stack

aws_xray_sdk/ext/aiohttp/client.py

@@ -2,12 +2,12 @@
 AioHttp Client tracing, only compatible with Aiohttp 3.X versions
 """
 import aiohttp
-import traceback
 
 from types import SimpleNamespace
 
 from aws_xray_sdk.core import xray_recorder
 from aws_xray_sdk.core.models import http
+from aws_xray_sdk.core.utils import stacktrace
 from aws_xray_sdk.ext.util import inject_trace_header, strip_url
 
 # All aiohttp calls will entail outgoing HTTP requests, only in some ad-hoc
@@ -51,7 +51,7 @@ async def end_subsegment_with_exception(session, trace_config_ctx, params):
     subsegment = xray_recorder.current_subsegment()
     subsegment.add_exception(
         params.exception,
-        traceback.extract_stack(limit=xray_recorder._max_trace_back)
+        stacktrace.get_stacktrace(limit=xray_recorder._max_trace_back)
     )
 
     if isinstance(params.exception, LOCAL_EXCEPTIONS):

aws_xray_sdk/ext/aiohttp/middleware.py

@@ -1,12 +1,12 @@
 """
 AioHttp Middleware
 """
-import traceback
 from aiohttp import web
 from aiohttp.web_exceptions import HTTPException
 
 from aws_xray_sdk.core import xray_recorder
 from aws_xray_sdk.core.models import http
+from aws_xray_sdk.core.utils import stacktrace
 from aws_xray_sdk.ext.util import calculate_sampling_decision, \
     calculate_segment_name, construct_xray_header, prepare_response_header
 
@@ -69,7 +69,7 @@ async def middleware(request, handler):
         # Store exception information including the stacktrace to the segment
         response = None
         segment.put_http_meta(http.STATUS, 500)
-        stack = traceback.extract_stack(limit=xray_recorder.max_trace_back)
+        stack = stacktrace.get_stacktrace(limit=xray_recorder.max_trace_back)
         segment.add_exception(err, stack)
         raise
     finally:

aws_xray_sdk/ext/django/middleware.py

@@ -1,8 +1,8 @@
 import logging
-import traceback
 
 from aws_xray_sdk.core import xray_recorder
 from aws_xray_sdk.core.models import http
+from aws_xray_sdk.core.utils import stacktrace
 from aws_xray_sdk.ext.util import calculate_sampling_decision, \
     calculate_segment_name, construct_xray_header, prepare_response_header
 
@@ -87,5 +87,5 @@ def process_exception(self, request, exception):
         segment = xray_recorder.current_segment()
         segment.put_http_meta(http.STATUS, 500)
 
-        stack = traceback.extract_stack(limit=xray_recorder._max_trace_back)
+        stack = stacktrace.get_stacktrace(limit=xray_recorder._max_trace_back)
         segment.add_exception(exception, stack)

aws_xray_sdk/ext/flask/middleware.py

@@ -1,9 +1,8 @@
-import traceback
-
 import flask.templating
 from flask import request
 
 from aws_xray_sdk.core.models import http
+from aws_xray_sdk.core.utils import stacktrace
 from aws_xray_sdk.ext.util import calculate_sampling_decision, \
     calculate_segment_name, construct_xray_header, prepare_response_header
 
@@ -86,7 +85,7 @@ def _handle_exception(self, exception):
             return
 
         segment.put_http_meta(http.STATUS, 500)
-        stack = traceback.extract_stack(limit=self._recorder._max_trace_back)
+        stack = stacktrace.get_stacktrace(limit=self._recorder._max_trace_back)
         segment.add_exception(exception, stack)
         self._recorder.end_segment()