Add Support for Pre bootstrap commands in Windows Node Groups

[niranjan94]

Description

Allows the specification of preBootstrapCommands in the node group spec for windows. Users can run custom powershell commands on instance start before the instance is bootstrapped for EKS.

Resolves #2003

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the site/content directory)
• Manually tested
• Added labels for change area (e.g. area/nodegroup), target version (e.g. version/0.12.0) and kind (e.g. kind/improvement)
• Make sure the title of the PR is a good description that can go into the release notes

[niranjan94]

@sayboras @martina-if @cPu1 please review when possible.

---

The tests started failing after rebasing over the latest master. Seems to be failing in the codegen stage. Unable to find CloudFormationAPI in any go files under this path. But can find it defined correctly under pkg/eks/mocks/CloudFormationAPI.go. The tests also pass fine locally. I'm not sure how to fix this. Would be really helpful if you could point me in the right direction. Thanks 😄

The error log from Circle CI:

Generating deepcopy funcs
>> Removing /tmp/tmp.BaNKKO
time go run ./cmd/schema/generate.go userdocs/src/usage/schema.md
real	0m 51.86s
user	1m 34.23s
sys	0m 6.27s
mkdir -p vendor/github.com/aws/
ln -sfn "/go/pkg/mod/github.com/weaveworks/aws-sdk-go@v1.25.14-0.20191218135223-757eeed07291" vendor/github.com/aws/aws-sdk-go
time env GOBIN=/go/bin go generate ./pkg/eks/mocks
Unable to find CloudFormationAPI in any go files under this path
pkg/eks/mocks/mocks.go:16: running "/go/bin/mockery": exit status 1
Command exited with non-zero status 1

[sayboras]

@niranjan94 thanks for your pointing this out. I got this fixed in #2021, but this PR might take some time to land in.

So I have created another one to fix this issue #2097. If this is blocking you, kindly help to apply the change here as well.

Sorry for any inconvenience caused.

[sayboras]

@niranjan94 the fix got merged into master, so simple rebase should fix the build failure. Thanks

[niranjan94]

@sayboras the build passes now. Thank you ! :)

[sayboras]

@sayboras the build passes now. Thank you ! :)

You might need to rebase one more time to fix the error with link-checker, now link-check only runs if there is changes on related files.

[michaelbeaumont]

@niranjan94 do you want to run these commands once at instance launch or every time the instance starts? At the moment (with your branch) they are executed only once, at launch.

[niranjan94]

@michaelbeaumont good point. I had overlooked this.

Yes, currently this PR runs it only once at launch. But I see that linux nodes use runcmd cloudconfig directive for pre-bootstrap commands which run at each boot.

I will make changes to this PR to ensure this runs on every boot too to keep the behaviour consistent with linux nodes (Will take care to ensure the kubernetes windows bootstrap command runs only once though)

[niranjan94]

@michaelbeaumont I have made the changes to ensure the pre-bootstrap commands run on every boot, consistent with the behavior of linux nodes. Please review when possible 😄

[michaelbeaumont]

@niranjan94 I think the precmd commands are only run once at launch for linux as well, which functionality do you need? (sorry for the confusion)
https://github.com/weaveworks/eksctl/blob/aaeab00f8173eded3388ae51b5b6465de1ae5230/pkg/cloudconfig/cloudconfig.go#L22

[niranjan94]

@michaelbeaumont you're right again 😄 . I completely misunderstood the runcmd documentation and wrongly assumed it runs at every launch. 🤦

My previous implementation was correct. Will revert the recent commit.

• New: Windows: Uses <powershell></powershell> user data directive. Runs once at first boot.
• Existing: Linux: Uses runcmd cloud-config directive. Runs once at first boot.

Windows & linux implementations are inline with each other on the behaviour of pre-bootstrap commands.

[michaelbeaumont]

OK, sounds good. I only asked initially because I wanted to be sure that's the functionality you intended it to have. thanks!