[WIP] Embed example templates into clusterawsadm

[randomvariable]

What this PR does / why we need it:
Removes gettext by starting to embed the templates into clusterawsadm.

User will run the following to create their examples:

clusterawsadm alpha config init --cluster-name default --ssh-key-name default --control-plane-instance-type t3.medium <etc...>

Which will write the same outputs as before.

Also moving the examples to a top-level /examples directory for better visibility. Don't think they need to live under /cmd/clusterctl/examples

These files are used by a Bazel rule to generate a go file with the files zipped into a Go virtual file stream which is then used by the CLI to generate the examples as rendered Go templates.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #299

Special notes for your reviewer:

Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

This PR will require changes to e2e, so will wait for #606 before completion.

Release note:

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@randomvariable: The following tests failed, say /retest to rerun them all:

Test name	Commit	Details	Rerun command
pull-cluster-api-provider-aws-verify-boilerplate	9757cd0	link	/test pull-cluster-api-provider-aws-verify-boilerplate
pull-cluster-api-provider-aws-bazel-verify	9757cd0	link	/test pull-cluster-api-provider-aws-bazel-verify
pull-cluster-api-provider-aws-bazel-test	9757cd0	link	/test pull-cluster-api-provider-aws-bazel-test

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[chuckha]

I'm torn on the config file vs CLI args

On the one hand CLI args are easy, but on the other had I feel like this has the potential to get complex and CLI flags are not great for repeatability/infrastructure as code. Like, I can check in a configuration file but I guess checking in a command line to run isn't as easy

[randomvariable]

Actually agree on this.

Only doing CLI flags as equivalents of the environment variables as used by envsubst in generate-yaml.sh.

What behaviour do we want to keep, and what should be jettisoned.

Don't see the point, for example of having the instance type env vars when we as cluster api devs can use kustomize patches for our workflows, and an end user should be expected to inspect and edit the cluster and machine yamls.

[randomvariable]

How about separate commands for cluster, machine and provider components, but with the machine command, you can pass in --cluster-config cluster.yaml and it will generate machine.yamls with the same cluster name and ssh key?

[chuckha]

so the CLI might look something like this:

clusterawsadm alpha config init cluster
clusterawsadm alpha config init machine --cluster-config cluster.yaml
clusterawsadm alpha config init provider-components

What would cluster.yaml look like?

Maybe something like?

clusterName: my-cluster
sshKeyName: my-ssh-key-name

[randomvariable]

Was thinking of exposing the user to the real cluster object at this stage rather than present a clusterawsadm abstraction, but using the cluster object as a hint for some of the fields for new machines.

[chuckha]

ah so, the output of clusterawsadm alpha config init cluster would be fed into clusterawsadm alpha config init machine --cluster-config cluster.yaml ?

[ashish-amarnath]

That's how I thought this would work. This will be kinda guiding the user through the steps to help them understand what they are getting and what is all under their control.

[randomvariable]

Yup, that's exactly it.

[vincepri]

/milestone Next

Feel free to change if necessary.

[randomvariable]

The underlying issue is v1alpha1

Going to finish this one before #612 .

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[detiber]

closing, we can reconsider down the line.

/close

[k8s-ci-robot]

@detiber: Closed this PR.

In response to this:

closing, we can reconsider down the line.

/close

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