THREESCALE-7961: Use sum_irate instead of sum_rate

[sergioifg94]

Description

Link to JIRA: https://issues.redhat.com/browse/THREESCALE-7961

Add logic to use sum_irate in monitoring queries when the Openshift version is greater or equal than 4.9. Keep using sum_rate when the Openshift version is less than 4.9.

Verification steps

1. On an Openshift 4.9 (or above) cluster
2. Install 3scale operator from this PR and the monitoring stack
3. Create an APIManager with monitoring enabled
4. Verify that the Grafana dashboards that use sum_rate use now sum_irate and show data
5. On an Openshift 4.8 (or below) cluster
6. Repeat steps 2 and 3
7. Verify that the Grafana dashboards continue using sum_rate and show data

[eguzki]

I understand the motivation of this implementation based on the reflect package.

I am ok with it, but I would like to share that IMHO the complexity added to solve a relatively simple use case does not pay off.

Some (if not all) the dashboard templates have a new parameter called SumRate. I would add them to the data struct and the value passed to the SumRate will be computed based on the logic you implemented.

For example, in pkg/3scale/amp/component/generic_monitoring.go

func KubernetesResourcesByNamespaceGrafanaDashboard(sumRate string, ns string, appLabel string) *grafanav1alpha1.GrafanaDashboard {
	data := &struct {
		Namespace string
                SumRate string
	}{
		ns, sumRate,
	}
	return &grafanav1alpha1.GrafanaDashboard{
		ObjectMeta: metav1.ObjectMeta{
			Name: "kubernetes-resources-by-namespace",
			Labels: map[string]string{
				"monitoring-key": common.MonitoringKey,
				"app":            appLabel,
			},
		},
		Spec: grafanav1alpha1.GrafanaDashboardSpec{
			Json: assets.TemplateAsset("monitoring/kubernetes-resources-by-namespace-grafana-dashboard-1.json.tpl", data),
			Name: fmt.Sprintf("%s/kubernetes-resources-by-namespace-grafana-dashboard-1.json", ns),
		},
	}
}

The caller would be:

sumRate, err := helper.SumRateForOpenshiftVersion(r.Context(), r.Client())  
if err != nil {                                                             
    return reconcile.Result{}, err                                          
}                  

grafanaDashboard := component.KubernetesResourcesByNamespaceGrafanaDashboard(sumRate, r.apiManager.Namespace, *r.apiManager.Spec.AppLabel)
err = r.ReconcileGrafanaDashboard(grafanaDashboard, reconcilers.GenericGrafanaDashboardsMutator)   
if err != nil {                                                                                                  
    return reconcile.Result{}, err                                                                               
}                                                                                                                
                                                

[sergioifg94]

Thanks @eguzki I followed your suggestion and simplified the inclusion of the SumRate parameter into the templates

[eguzki]

is it being used?

[sergioifg94]

Good catch, I missed it when removing the stuff from the initial implementation. Fixed it now

[codeclimate]

Code Climate has analyzed commit a626076 and detected 31 issues on this pull request.

Here's the issue category breakdown:

Category	Count
Complexity	2
Duplication	10
Style	19

View more on Code Climate.