AWS X-Ray ERROR:aws_xray_sdk.core.context:cannot find the current segment/subsegment

Question

我们最近通过以下方式将 X-Ray 添加到我们的代码中：

from aws_xray_sdk.core import xray_recorder
from aws_xray_sdk.core import patch_all

patch_all()

虽然这运行在 AWS Lambda 上很好，但是在调用 ElasticSearch 期间尝试在本地运行时，我们遇到以下异常：

ERROR:aws_xray_sdk.core.context:cannot find the current segment/subsegment, please make sure you have a segment open
queryCustomers - DEBUG - Caught exception for <function search_customer at 0x10bfcf0d0>
Traceback (most recent call last):
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/chalice/app.py", line 659, in _get_view_function_response
    response = view_function(**function_args)
  File "/Users/jameslin/projects/test-project/src/app.py", line 57, in search_customer
    return query[0:size].execute().to_dict()['hits']['hits']
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/elasticsearch_dsl/search.py", line 639, in execute
    **self._params
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/elasticsearch/client/utils.py", line 73, in _wrapped
    return func(*args, params=params, **kwargs)
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/elasticsearch/client/__init__.py", line 632, in search
    doc_type, '_search'), params=params, body=body)
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/elasticsearch/transport.py", line 312, in perform_request
    status, headers, data = connection.perform_request(method, url, params, body, ignore=ignore, timeout=timeout)
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/elasticsearch/connection/http_requests.py", line 71, in perform_request
    prepared_request = self.session.prepare_request(request)
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/aws_xray_sdk/ext/requests/patch.py", line 38, in _inject_header
    inject_trace_header(headers, xray_recorder.current_subsegment())
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/aws_xray_sdk/core/recorder.py", line 251, in current_subsegment
    entity = self.get_trace_entity()
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/aws_xray_sdk/core/recorder.py", line 316, in get_trace_entity
    return self.context.get_trace_entity()
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/aws_xray_sdk/core/context.py", line 93, in get_trace_entity
    return self.handle_context_missing()
  File "/Users/jameslin/virtualenvs/test-project/lib/python3.6/site-packages/aws_xray_sdk/core/context.py", line 118, in handle_context_missing
    raise SegmentNotFoundException(MISSING_SEGMENT_MSG)
aws_xray_sdk.core.exceptions.exceptions.SegmentNotFoundException: cannot find the current segment/subsegment, please make sure you have a segment open

我不知道他的意思以及如何摆脱它，我的 google 尝试没有给出很多相关结果，我也尝试运行在本地安装 X 射线守护程序，但仍然遇到同样的问题：

./xray_mac -o -n ap-southeast-2

Answer 1

当您的代码在启用跟踪的 AWS Lambda 上运行ning 时，Lambda 容器将生成一个表示整个函数调用的段。它还将上下文设置为环境变量，因此 SDK 可以 link 在函数内创建的任何子分段返回到 parent 分段。

如果您运行在本地使用相同的代码，SDK 仍会尝试为实际功能代码创建子段，但找不到任何上下文，因此会抛出您发布的错误。

要解决此问题，您需要设置一些环境变量以确保 SDK 具有与运行在实际 Lambda 容器上相同的信息。

通过将 LAMBDA_TASK_ROOT 设置为您想要的任何值（只有密钥的存在很重要），确保 SDK 认为它在 Lambda 容器上运行ning。您可以在此处查看源代码：https://github.com/aws/aws-xray-sdk-python/blob/master/aws_xray_sdk/core/lambda_launcher.py
设置 LAMBDA_TRACE_HEADER_KEY 以便函数具有跟踪上下文。该值必须是跟踪 header，您可以在此处查看更多详细信息：https://docs.aws.amazon.com/lambda/latest/dg/lambda-x-ray.html

此解决方法并不理想，因为它需要用户端进行额外的代码更改。我们希望为在本地测试 X-Ray 检测的 Lambda 函数提供更好的客户体验。您介意分享有关您如何进行本地测试以及您希望 X-Ray 跟踪在此类测试环境中如何工作的更多详细信息，以便我们可以更好地改进您的用例吗？

AWS X-Ray ERROR:aws_xray_sdk.core.context:cannot find the current segment/subsegment

AWS X-Ray ERROR:aws_xray_sdk.core.context:cannot find the current segment/subsegment

amazon-web-services

aws-xray