AWS X-Ray Remote Sampler Part 1 - Initial Classes and Rules Poller Implementation

[jj22ee]

Description

This is an initial PR to address #3305 in order for OTel Python to support X-Ray Remote Sampling. A series of PRs to fully implement this feature will follow.

Changes:

• Add xray sampler under opentelemetry-sdk-extension-aws
• Code changes:
  • Add Sampling Client class to communicate with X-Ray Service for Sampling Rules/Targets
  • Add X-Ray Sampling Rules/Targets/Statistics class to help represent the Sampling related data from X-Ray
  • Added the AwsXRayRemoteSampler skeleton class
    • Ensure AwsXRayRemoteSampler is a ParentBased Sampler, with internal logic inside _AWSXRayRemoteSampler
    • Run poller upon instantiation to regularly obtain X-Ray Sampling Rules from X-Ray

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

This PR is not a full implementation of the sampler, so it cannot be tested for correct functionality.
Right now, it currently always return a Parent Based decision or a DROP decision as a placeholder.

• Unit Tests

A couple more PRs will follow-up to complete the implementation, which should look like this Sampler code from the AWS ADOT repo. At that point in the future, a full E2E integration test will be run.

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[xrmx]

Question: would it make sense to add this to https://github.com/open-telemetry/opentelemetry-python-contrib/tree/main/sdk-extension/opentelemetry-sdk-extension-aws instead of creating a new package?

[jj22ee]

Yeah that makes sense, opentelemetry-sdk-extension-aws seems to hold all aws components... except the AWS XRay Propagator that I based my work off of...

I synced with package owner @srprash, there is no concern with moving this Sampler to the SDK Extensions.

[srprash]

Minor comments. Overall LGTM.