Add tests for CRD CEL validation

[bjee19]

The gateway-api repository has tests for their CEL validation on CRDs found here: https://github.com/kubernetes-sigs/gateway-api/tree/main/pkg/test/cel.

Currently we manually test our CEL validation on CRDs, however it could be beneficial to follow the standard set in the gateway-api repository and create functional tests for them.

Acceptance

• Verify that all CEL statements work as expected for the CRDs we own.

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Notes

CEL is available as of K8S v1.25

[iaiw3br]

@bjee19 hi! I want to help you with this issue. Can you describe what I need to do ?
It's will be my the first contribute in this project, or maybe you have a smaller problem I could start with ?

[bjee19]

Hey @iaiw3br, thanks for your interest in our project!

This issue has to do with some Common expression language validation we put on our CRDs. This is the kubebuilder explanation of various possible CRD validations, and here's what it looks like in our code:

nginx-gateway-fabric/apis/v1alpha1/nginxgateway_types.go

Lines 66 to 73 in a382a1c

	// NginxGatewayStatus defines the state of the NginxGateway.
	type NginxGatewayStatus struct {
	// +optional
	// +listType=map
	// +listMapKey=type
	// +kubebuilder:validation:MaxItems=8
	Conditions []metav1.Condition `json:"conditions,omitempty"`
	}

We currently don't have any tests for these CEL validation statements, so we have to do it all manually by creating the resource and ensuring it throws an error when we create a CRD which breaks the CEL validation.

We'd like to add tests for all our CRDs so we can avoid having to rely on our manual testing. Here's an example test of what we're looking for from the gateway api repo. Where you can see how thoroughly they test their CEL validation on the HTTPRoute resource .

We don't have as much CEL validation so it will be much smaller, but let me know if you have any more questions or if you'd like to choose something smaller. Here's another story #1939 which probably is smaller if that interests you more.