Add Resource Requirements for Cryostat deployment

[ebaron]

A user should be able to specify resource requests/limits for the main Cryostat deployment using the Cryostat CRD.

[andrewazores]

Related to #277

[jaadbarg]

Hi @ebaron, I'd like to take this one

[ebaron]

ResourceRequirements type: https://pkg.go.dev/k8s.io/api/core/v1#ResourceRequirements

[ebaron]

OLM Spec Descriptor: https://github.com/openshift/console/blob/master/frontend/packages/operator-lifecycle-manager/src/components/descriptors/reference/reference.md#2-resourcerequirements

[ebaron]

Resource requirements are set at the container level, so we should expose properties for each of the 3 containers. Something like this perhaps:

type CryostatSpec struct {
...
	// Define resource requirements for containers within the main Cryostat deployment
	// +optional
	// +operator-sdk:csv:customresourcedefinitions:type=spec
	Resources ResourceConfigList `json:"resources,omitempty"`
}

// ResourceConfigList includes resource requirements settings for each container in the main Cryostat deployment
type ResourceConfigList struct {
	// Resource requirements for the Cryostat application
	// +optional
	// +operator-sdk:csv:customresourcedefinitions:type=spec,xDescriptors={"urn:alm:descriptor:com.tectonic.ui:resourceRequirements"}
	CoreResources corev1.ResourceRequirements `json:"coreResources,omitempty"`
	// Resource requirements for the JFR Data Source container
	// +optional
	// +operator-sdk:csv:customresourcedefinitions:type=spec,xDescriptors={"urn:alm:descriptor:com.tectonic.ui:resourceRequirements"}
	DataSourceResources corev1.ResourceRequirements `json:"dataSourceResources,omitempty"`
	// Resource requirements for the Grafana container
	// +optional
	// +operator-sdk:csv:customresourcedefinitions:type=spec,xDescriptors={"urn:alm:descriptor:com.tectonic.ui:resourceRequirements"}
	GrafanaResources corev1.ResourceRequirements `json:"grafanaResources,omitempty"`
}