aiohttp client instrumentation: "leaking" attributes in metrics

[sboisson]

Describe your environment

OS: Any
Python version: > Python 3.9
Package version: (e.g., 0.46.0)

What happened?

Report metrics with attributes from previous requests (like HTTP status or error type)

Steps to Reproduce

Use the same ClientSession for several requests.
After a 1st successful request (HTTP status 200), have a 2nd request raising an exception (ex: timeout)

Expected Result

Second request should not record a metric with HTTP status 200

Actual Result

The second request will record a metric with HTTP status 200 and a error.type set to TimeoutException

Additional context

This probably caused by metrics_attributes variable only created at creation of ClientSession an used in tracing all the requests made by this session
in opentelemetry.instrumentation.aiohttp_client.package:create_trace_config()

Would you like to implement a fix?

Yes

Tip

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