how can i receive metrics except trace

Describe your environment

OS: linux
Python version: 3.10
Package version: (e.g., 0.46.0)
Error in exception logger

Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/tornado/web.py", line 1767, in _execute
    result = self.prepare()
  File "/otel-auto-instrumentation/wrapt/wrappers.py", line 670, in __call__
    return self._self_wrapper(self.__wrapped__, self._self_instance,
  File "/otel-auto-instrumentation/opentelemetry/instrumentation/tornado/__init__.py", line 413, in _prepare
    ctx = _start_span(tracer, handler)
  File "/otel-auto-instrumentation/opentelemetry/instrumentation/tornado/__init__.py", line 522, in _start_span
    span, token = _start_internal_or_server_span(
  File "/otel-auto-instrumentation/opentelemetry/instrumentation/utils.py", line 147, in _start_internal_or_server_span
    span = tracer.start_span(
  File "/otel-auto-instrumentation/opentelemetry/sdk/trace/__init__.py", line 1118, in start_span
    parent_span_context = trace_api.get_current_span(
  File "/otel-auto-instrumentation/opentelemetry/trace/propagation/__init__.py", line 48, in get_current_span
    span = get_value(_SPAN_KEY, context=context)
  File "/otel-auto-instrumentation/opentelemetry/context/__init__.py", line 97, in get_value
    return context.get(key) if context is not None else get_current().get(key)
AttributeError: 'NoneType' object has no attribute 'get'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/tornado/web.py", line 1839, in _handle_request_exception
    self.log_exception(*sys.exc_info())
  File "/otel-auto-instrumentation/wrapt/wrappers.py", line 670, in __call__
    return self._self_wrapper(self.__wrapped__, self._self_instance,
  File "/otel-auto-instrumentation/opentelemetry/instrumentation/tornado/__init__.py", line 442, in _log_exception
    _record_on_finish_metrics(server_histograms, handler, error)
  File "/otel-auto-instrumentation/opentelemetry/instrumentation/tornado/__init__.py", line 635, in _record_on_finish_metrics
    server_histograms[MetricInstruments.HTTP_SERVER_RESPONSE_SIZE].record(
  File "/otel-auto-instrumentation/opentelemetry/sdk/metrics/_internal/instrument.py", line 264, in record
    self._measurement_consumer.consume_measurement(
  File "/otel-auto-instrumentation/opentelemetry/sdk/metrics/_internal/measurement_consumer.py", line 82, in consume_measurement
    self._sdk_config.exemplar_filter.should_sample(
  File "/otel-auto-instrumentation/opentelemetry/sdk/metrics/_internal/exemplar/exemplar_filter.py", line 131, in should_sample
    span = trace.get_current_span(context)
  File "/otel-auto-instrumentation/opentelemetry/trace/propagation/__init__.py", line 48, in get_current_span
    span = get_value(_SPAN_KEY, context=context)
  File "/otel-auto-instrumentation/opentelemetry/context/__init__.py", line 97, in get_value
    return context.get(key) if context is not None else get_current().get(key)
AttributeError: 'NoneType' object has no attribute 'get'
500 GET /health (10.231.248.6) 2.72ms

What happened?

I used the auto-instrumentation approach to integrate OpenTelemetry into a Python project, but encountered this issue above. Our goal is to collect only metrics data without generating any spans. Is there a way to achieve this? Can it be done through environment variables?

Steps to Reproduce

empty

Expected Result

empty

Actual Result

empty

Additional context

empty

Would you like to implement a fix?

None

Tip

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Start with opentelemetry/instrumentation/tornado/init.py, especially _prepare, _log_exception, and _record_on_finish_metrics, then inspect the SDK context and exemplar files named in the traceback. Reproduce the failure with the auto-instrumented Tornado health endpoint and determine whether metrics-only configuration is supported. Done means metrics can be collected without spans and without the NoneType exception, or the supported configuration is documented.