fix: Avoid segfault when scheduler resources is nil

[Sovietaced]

This is a fix for a segfault that occurs when resources are nil in the scheduler spec. The current code tries to dereference *scheduler.Spec.Resources outside of the conditional that checks for nil.

Follow up on #298 with unit tests since @jpoler is no longer responsible for our Armada deployment.

[dejanzele]

Hey @Sovietaced,

Thanks for raising this issue and fixing it!

The core issue was a typo in the Scheduler CRD webhook configuration which wasn't wiring up the mutating webhook properly and it wasn't getting triggered, hence it wasn't defaulting the resources.

This is fixed in #301

This PR also contains updates to work with latest version of Armada which is v0.5.0, it contains a big documentation redo with better examples...

We plan on merging it tomorrow.

Can you please take a look at this PR?

[Sovietaced]

This is fixed in #301

Thank you, will close this.

[Sovietaced]

@dejanzele this does not appear to be fixed in the pull request you mentioned. We are using the latest operator version 0.2.0 and we just hit this when we didn't specify resources for the scheduler.

2024-07-14T23:34:03Z	INFO	setup	Observed a panic in reconciler: runtime error: invalid memory address or nil pointer dereference	{"controller": "scheduler", "controllerGroup": "install.armadaproject.io", "controllerKind": "Scheduler", "Scheduler": {"name":"armada-scheduler","namespace":"armada"}, "namespace": "armada", "name": "armada-scheduler", "reconcileID": "65a6210c-5e4b-4e38-b7bc-d5d1c6bf7929"}
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x15e401f]

goroutine 433 [running]:
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Reconcile.func1()
	/home/runner/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:111 +0x1e5
panic({0x17a0040?, 0x28ebef0?})
	/opt/hostedtoolcache/go/1.22.3/x64/src/runtime/panic.go:770 +0x132
github.com/armadaproject/armada-operator/internal/controller/install.createSchedulerDeployment(0xc000170f08)
	/home/runner/work/armada-operator/armada-operator/internal/controller/install/scheduler_controller.go:362 +0xe7f
github.com/armadaproject/armada-operator/internal/controller/install.generateSchedulerInstallComponents(0xc000170f08, 0xc0002507e0)

[dejanzele]

Hi @Sovietaced,

I will recheck today.