AWS SDK Instrumentation should use AWS SDK values for `rpc` attributes

Description

In the aws sdk instrumentation package, rpc attributes are set from the normalizedRequest.

https://github.com/aspecto-io/opentelemetry-ext-js/blob/243e19bcebb5f95df5b4a68cbf675aa6351ca3fb/packages/instrumentation-aws-sdk/src/utils.ts#L40-L47

normalizedRequest (v2 and v3) modify the request metadata values returned from the AWS SDK like this:

https://github.com/aspecto-io/opentelemetry-ext-js/blob/243e19bcebb5f95df5b4a68cbf675aa6351ca3fb/packages/instrumentation-aws-sdk/src/utils.ts#L15-L23

Specifically:

• It converts the service name .toLowerCase()
• It converts the operation name .toCamelCase()

However, the specs for AWS SDK instrumentation give examples that contradict these patterns.

- ref: rpc.service
brief: "The name of the service to which a request is made, as returned by the AWS SDK."
examples:
    - DynamoDB
    - S3
- ref: rpc.method
brief: "The name of the operation corresponding to the request, as returned by the AWS SDK"
examples:
    - GetItem
    - PutItem

Action Items

Based on the examples, we should return S3 instead of s3 and ListBuckets instead of listBuckets (for example).

This means using toUpperCase() and a modified version of toCamelCase() with the first character Upper Case.

[Oberon00]

@anuraaga please take a look, it seems like the spec could use some improvement in that area.

[blumamir]

According to the cited thread you should be able to retrieve the operation name from the metadata. I would create a spec issue, asking for clarification. My gut feeling is that in doubt you should rather report what you have as-is than doing any string manipulation.

Thank you @Oberon00 for taking the time to read and comment here. I agree with your comment in general. Unfortunately, for aws-sdk js the situation is very complex:

in v2, the operation name is set with PascalCase in the apis (see example) but then later on changed to camelCase somewhere in the code which is what is accessible to the patching code. in v3, both the service name and the method are not accessible at all! there is simply no way to retrieve them other than extracting them from the class name or digging into some very deep private attributes which are not structured or documented.

I think that the sentence “as returned by the AWS SDK” is simply not valid for JS sdk specifically.

Since the spec is (deliberately?) blurry about what value should be set for these attributes, I’m ok with applying common sense and produce values (i.e PascalCase) that are consistent between v2, v3, the generic API reference, and the examples in otel spec. However, I will be happy if someone wants to take this issue, research all the complexity, and lead a discussion in the spec repo or anywhere else. I can help with such effort but it’s too time-consuming for me to lead it myself.