Implementations SHOULD preserve the order in which attributes are set

[codeboten]

To be compliant with the tracing spec, Implementations SHOULD preserve the order in which attributes are set

https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/trace/api.md#set-attributes

[lzchen]

I don't see this as a requirement for attributes?

[ffe4]

https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/common/common.md#attributes

Attributes SHOULD preserve the order in which they're set.

[ffe4]

Attributes in sdk.trace.Span are implemented as a BoundedDict which is already ordered. What else do we need to do here?

[ocelotl]

I think we are ok with the current implementation. The order of the attributes is being used to select which key to override (the oldest one) when the maximum size of the dictionary is reached.