Add AWS SNS event callback during cluster setup (Ray 1.11.0)

[rkenmi]

This PR adds a SNS event callback for each Ray cluster setup event. Tested with ray up, ray exec.

To configure, the events field must be added to the cluster config YAML

events takes the following arguments:

• notification_uri: Cloud specific resource identifier for dispatching events to. This may vary based on which cloud provider you use (e.g. GCP, AWS, Azure). For this implementation, SNS topic ARNs are taken as valid input.
• parameters: Arbitrary key-value parameters that you want to include into the payload of each callback. This might be useful, if for example, you need to pass in additional metadata for a particular Ray job, such as the job ID.

This PR is rebased off of the experimental branch with 1.11.0. Old PR: https://github.com/amzn/amazon-ray/pull/96

Related issue number

Checks

• [x] I'm working against the latest source on the experimental branch.
• [x] I've run scripts/format.sh to lint the changes in this PR.
• [ ] I've included any doc changes needed.
• [x] I've made sure the tests are passing. Note that there might be a few flaky tests.
• Testing Strategy
  • [ ] Unit tests
  • [ ] Release tests
  • [ ] This PR is not tested :(

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[rkenmi]

There will definitely be examples, for sure 🙂 . This would be something to include into the Ray docs as well.