[OTel] Non-string attributes are being sent as an empty string

[vtfr]

Summary

Non-string attributes are being sent as an empty string.

Steps To Reproduce

• Configure an Open Telemetry TraceProvider using sentry's SpanProcessor
• Start a Span
• Set a non-string Attribute (such as semconv.HTTPStatusCode)
• Verify that in the dashboard this Attribute is an empty string, despite it's value being non-zero

Expected Behavior

• All attributes should reach Sentry's Dashboard with their respective values.

SDK

• sentry-go version: v0.22.0
• Go version: 1.19
• Using Go Modules? yes

Sentry

• Using hosted Sentry in sentry.io? yes
• Anything particular to your environment that could be related to this issue? No.

Additional context

The problem seems to be due to these two calls:

sentry-go/otel/span_processor.go

Line 125 in feb3495

attributes[kv.Key] = kv.Value.AsString()

sentry-go/otel/span_processor.go

Line 128 in feb3495

resource[kv.Key] = kv.Value.AsString()

As stated by Value.AsString method's doc:

// AsString returns the string value. Make sure that the Value's type
// is STRING.

Probably the code's intention was to use Value.Emit(), instead. This method returns the string representation of the Value's data.