Expose PlatformFields field in order for it to be persisted in state

[julienduchesne]

Summary

We run windows clusters with the ECS_ENABLE_CPU_UNBOUNDED_WINDOWS_WORKAROUND environment variable. We also reboot our instances in order to install some software when we start them. When rebooting, the tasks that have already been received by the instance are persisted to disk but the variable where ECS_ENABLE_CPU_UNBOUNDED_WINDOWS_WORKAROUND is not exposed in the JSON. These tasks are therefore restarted with 2 CPU units instead of 0 (unbounded). PlatformFields must be persisted in order to maintain consistent behavior.

Thanks

Implementation details

Converted PlatformFields to a public attribute and added json field tags.

Testing

Runs on our ECS clusters

• Builds on Linux (make release)
• Builds on Windows (go build -out amazon-ecs-agent.exe ./agent)
• Unit tests on Linux (make test) pass
• Unit tests on Windows (go test -timeout=25s ./agent/...) pass
• Integration tests on Linux (make run-integ-tests) pass
• Integration tests on Windows (.\scripts\run-integ-tests.ps1) pass
• Functional tests on Linux (make run-functional-tests) pass
• Functional tests on Windows (.\scripts\run-functional-tests.ps1) pass

New tests cover the changes:

Description for the changelog

Licensing

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

[julienduchesne]

cc @jocgir @mouellet-coveo

[adnxn]

/ping @sharanyad: did you end up running the tests on this?

[sharanyad]

all tests pass.

[sharanyad]

Thanks for the contribution

[sharanyad]

@aws/aws-ecs-agent ptal

[richardpen]

This may need a changelog update.

[julienduchesne]

Hi, could you guys merge this please?

Also, could you take a look at my comment here: #1144 (comment)?

We are currently using a fork of amazon-ecs-agent and if I could get this issue and my other one sorted out, we could get back on the official version and that would be awesome.

Thanks a lot