set error.type to asgi-instrumentation attributes when having exceptions

[emdneto]

Description

Right now we only have the error.type for HTTP status code, but we should handle the exceptions and set it in error.type as well
Fixes #2699

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• tox

Does This PR Require a Core Repo Change?

• No.

Checklist:

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[pmcollins]

Just a style thing, but I'm wondering if it would be worthwhile to break this method into functions for readability. Perhaps those functions could stand to be further modularized, but this would be a step in that direction. Something like

        try:
            await self.instrument_app(attributes, receive, scope, send, span, span_name)
        except Exception as exc:  # pylint: disable=broad-except
            exception = exc
        finally:
            await self.cleanup(active_requests_count_attrs, attributes, exception, scope, span, start, token)

Not a blocking comment, just a suggestion while we're in here.

[lzchen]

Another suggestion would also to wait and implement this for the various instrumentations that still require this (like flask, wsgi (for metrics), django, etc) and see if there are any commonalities we can refactor out. Difficult to say what we can abstract/modularize without seeing more implementation.

[emdneto]

Agreed. Indeed, while reviewing the transition PRs I identified several instrumentations we are not handling exceptions and setting the exception in error.type, even for the ones that are already migrated to the new semconv. I will mark this as draft for now while I think in a better way to handle this. Maybe we'll have a better idea on the commonalities after more transitions.

[lzchen]

The -1 status code is a bit awkward. The current change is fine but I would like to brainstorm some ways we can abstract all of this logic out somehow. The following are probably required in some way or another and should be shared across all instrumentations (especially wsgi and asgi) : 1. Setting status code on span 2. Setting error attributes on span if recording and if status code is erroneous 3. Setting error attributes on metrics attributes if status code is erroneous 4. Setting error attributes on span/metrics in general.

[emdneto]

I wouldn't say I like it either. We are actually doing that in several places where we try to int the status_code, and if it fails, we set status_code as -1. Let me see what can I do here to improve the way we are handling this.