add http.status_code attribute to all Spans that have a lowLevelHttpResponse

[ecourreges-orange]

This one is fairly straight forward:
It adds the official OpenTelemetry http.status_code attribute which is mandatory, was missing and is very useful to know what happened to one's request.

Signed-off-by: CI-Bot for Emmanuel Courreges [email protected]

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[elharo]

This library uses OpenCensus, not OpenTelemetry.

Do you happen to know what the status of those two is? We really need to figure that out.

[ecourreges-orange]

This library uses OpenCensus, not OpenTelemetry.

I know but OpenTelemetry needs to be adopted eventually because OpenCensus will disappear in 2 years.

On top of this, OpenCensus already uses http.status_code as attribute name, which you can see from the fact that I am using an existing string variable for it.

Do you happen to know what the status of those two is? We really need to figure that out.

As you can see here, OpenTelemetry is still a work in progress, so if I were you, I would wait until it is stable and production ready to migrate to it, but it will be fairly straightforward because there is an OpenCensus bridge, and also the interfaces are very similar.

[elharo]

Why is this a long instead of an int? Status codes don't go past 5XX

[ecourreges-orange]

Because there is only long for integer attribute types in OpenCensus: https://javadoc.io/doc/io.opencensus/opencensus-api/0.12.2/io/opencensus/trace/AttributeValue.html

[ecourreges-orange]

@googlebot I signed it!

[ecourreges-orange]

@googlebot I signed it!

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