Adjust Networking metrics to follow OpenTelemetry semantic conventions

[antonfirsov]

Edit: for folks landing on this issue, I'm linking the final spec of the Metrics implemented in .NET 8.0: https://github.com/lmolkova/semantic-conventions/blob/dotnet8-metrics/docs/dotnet/README.md

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We are implementing the following metrics for .NET 8 with ad-hoc naming:

// Request metrics:
http-client-current-requests (scheme, host, port, method)
http-client-request-duration (scheme, host, port, method, status-code, protocol)
http-client-failed-requests  (scheme, host, port, method, status-code, protocol)

// Connection metrics:
http-client-current-connections      (protocol, scheme, host, port)
http-client-current-idle-connections (protocol, scheme, host, port)
http-client-connection-duration      (protocol, scheme, host, port)

// How long is a request waiting in the connection pool's queue:
http-client-requests-queue-duration  (protocol, scheme, host, port)

dns-lookups-requested(hostname)

We need to adjust these instruments to follow OpenTelemetry semantic conventions in naming and other aspects. Details TBD.

[ghost]

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Issue Details

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We have implemented the following metrics for .NET 8 with ad-hoc naming:

// Request metrics:
http-client-current-requests (scheme, host, port, method)
http-client-request-duration (scheme, host, port, method, status-code, protocol)
http-client-failed-requests  (scheme, host, port, method, status-code, protocol)

// Connection metrics:
http-client-current-connections      (protocol, scheme, host, port)
http-client-current-idle-connections (protocol, scheme, host, port)
http-client-connection-duration      (protocol, scheme, host, port)

// How long is a request waiting in the connection pool's queue:
http-client-requests-queue-duration  (protocol, scheme, host, port, ?method?)

dns-lookups-requested(hostname)

We need to adjust these instruments to follow OpenTelemetry semantic conventions. Details TBD.

Author:	antonfirsov
Assignees:	antonfirsov
Labels:	area-System.Net
Milestone:	8.0.0