SDK SHOULD NOT provide access to a Span's attributes besides its SpanContext

[codeboten]

To be compliant with the tracing spec, the SDK SHOULD NOT provide access to a Span's attributes besides its SpanContext

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

[shovnik]

Is the intent to make the attributes someone sets for a span harder to access using name mangling, because usually in python, making a user set properties private and only accessible with getters/setters seems strange. In python's case, can we not just say not to access the attributes in the doc and trust the user?

[anuraaga]

I agree with @shovnik in that it's best not to go too far if something isn't idiomatic in the language, or would add overhead. The recommendation is SHOULD NOT to reflect this expectation I think.

[lzchen]

This issue might be related. I think either approach of setting the properties to private (with a getter/setter) or trusting the user with how they interact with the API + include detailed documentation is fine. The important thing to ensure is that we are consistent with our approach, and not have a mixture of these two in our codebase.

[shovnik]

If the spec states that the SDK should not provide access the a Span's attributes besides the SpanContext, wouldn't making the properties private (not sure if fully private is possible) and adding a getter would provide access to the attributes anyways? I might be misunderstanding the first approach you suggested @lzchen .

[lzchen]

@shovnik
I was referring to the concept of "enforcing users to interact with our API" rather than doing whatever they want. There are several places in which this happens (calling Tracer() directly instead of trace.get_tracer(), accessing span.attributes directly instead of (potentially) span.get_attributes(), and in your case, simply calling span.attributes. It is difficult to prevent users from actually doing this, the question is whether or not we want to "make it difficult" for them to do this (with whatever mechanism we come up with i.e. name mangling, private attributes with gettors/setters, adding hidden arguments like here to prevent instantiation) or we are fine with just explicitly documenting our API and telling users you MUST interact with Opentelemetry ONLY using our APIs, and trust that they use it properly. Probably something to bring up during the weekly SIG.

[lzchen]

Perhaps take a look at this document: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/trace/sdk.md#additional-span-interfaces
Can we utilize this?