Incorporate metrics description from README.md as metric help

pkg/exporter/metrics.go

@@ -27,95 +27,114 @@ var (
 	computeCoresTotal = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_cores_total",
+		Help:      "Quota for number of compute cores per region and project",
 	}, []string{"region", "project"})
 
 	computeCoresUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_cores_used",
+		Help:      "Number of used compute cores per region and project",
 	}, []string{"region", "project"})
 
 	computeInstancesTotal = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_instances_total",
+		Help:      "Quota for number of compute instances per region and project",
 	}, []string{"region", "project"})
 
 	computeInstancesUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_instances_used",
+		Help:      "Number of used compute instances per region and project",
 	}, []string{"region", "project"})
 
 	computeFlavorsUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_flavors_used",
+		Help:      "Number of used compute flavors per type and region and project",
 	}, []string{"region", "project", "flavor"})
 
 	computeRamTotalMegabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_ram_total_megabytes",
+		Help:      "Quota for ram per region and project in megabytes",
 	}, []string{"region", "project"})
 
 	computeRamUsedMegabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "compute_ram_used_megabytes",
+		Help:      "Used ram per region and project in megabytes",
 	}, []string{"region", "project"})
 
 	dnsZonesTotal = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "dns_zones_total",
+		Help:      "Quota for number of DNS zones per region and project",
 	}, []string{"region", "project"})
 
 	dnsZonesUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "dns_zones_used",
+		Help:      "Number of used DNS zones per region and project",
 	}, []string{"region", "project"})
 
 	networkFloatingIPsTotal = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "network_floating_ips_total",
+		Help:      "Quota for number of floating IPs per region and project",
 	}, []string{"region", "project"})
 
 	networkFloatingIPsUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "network_floating_ips_used",
+		Help:      "Number of used floating IPs per region and project",
 	}, []string{"region", "project"})
 
 	networkLoadbalancersTotal = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "network_loadbalancers_total",
+		Help:      "Quota for number of load balancers per region and project",
 	}, []string{"region", "project"})
 
 	networkLoadbalancersUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "network_loadbalancers_used",
+		Help:      "Number of used load balancers per region and project",
 	}, []string{"region", "project"})
 
 	s3SpaceTotalBytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "s3_space_total_bytes",
+		Help:      "Quota for S3 space per region and project in bytes",
 	}, []string{"region", "project"})
 
 	s3SpaceUsedBytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "s3_space_used_bytes",
+		Help:      "Used S3 space per region and project in bytes",
 	}, []string{"region", "project"})
 
 	volumeSpaceTotalGigabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "volume_space_total_gigabytes",
+		Help:      "Quota for volume space per region and project in gigabytes",
 	}, []string{"region", "project"})
 
 	volumeSpaceUsedGigabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "volume_space_used_gigabytes",
+		Help:      "Number of used volume space per region and project in gigabytes",
 	}, []string{"region", "project"})
 
 	volumeVolumesTotalGigabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "volume_volumes_total",
+		Help:      "Quota for number of volumes per region and project",
 	}, []string{"region", "project"})
 
 	volumeVolumesUsedGigabytes = promauto.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: namespace,
 		Name:      "volume_volumes_used",
+		Help:      "Number of used volumes per region and project",
 	}, []string{"region", "project"})
 )