allow lowercasing of dimension values

fixes #90

Signed-off-by: Markus Blaschke <[email protected]>

Author: mblaschke

README.md

@@ -70,16 +70,16 @@ Application Options:
       --log.devel                          development mode [$LOG_DEVEL]
       --log.json                           Switch log output to json format [$LOG_JSON]
       --azure-environment=                 Azure environment name (default: AZUREPUBLICCLOUD) [$AZURE_ENVIRONMENT]
-      --azure-ad-resource-url=             Specifies the AAD resource ID to use. If not set, it defaults to ResourceManagerEndpoint for
-                                           operations with Azure Resource Manager [$AZURE_AD_RESOURCE]
-      --azure.servicediscovery.cache=      Duration for caching Azure ServiceDiscovery of workspaces to reduce API calls (time.Duration)
-                                           (default: 30m) [$AZURE_SERVICEDISCOVERY_CACHE]
+      --azure-ad-resource-url=             Specifies the AAD resource ID to use. If not set, it defaults to ResourceManagerEndpoint for operations with Azure Resource Manager
+                                           [$AZURE_AD_RESOURCE]
+      --azure.servicediscovery.cache=      Duration for caching Azure ServiceDiscovery of workspaces to reduce API calls (time.Duration) (default: 30m)
+                                           [$AZURE_SERVICEDISCOVERY_CACHE]
       --azure.resource-tag=                Azure Resource tags (space delimiter) (default: owner) [$AZURE_RESOURCE_TAG]
       --metrics.template=                  Template for metric name (default: {name}) [$METRIC_TEMPLATE]
       --metrics.help=                      Metric help (with template support) (default: Azure monitor insight metric) [$METRIC_HELP]
+      --metrics.dimensions.lowercase       Lowercase dimension values [$METRIC_DIMENSIONS_LOWERCASE]
       --concurrency.subscription=          Concurrent subscription fetches (default: 5) [$CONCURRENCY_SUBSCRIPTION]
-      --concurrency.subscription.resource= Concurrent requests per resource (inside subscription requests) (default: 10)
-                                           [$CONCURRENCY_SUBSCRIPTION_RESOURCE]
+      --concurrency.subscription.resource= Concurrent requests per resource (inside subscription requests) (default: 10) [$CONCURRENCY_SUBSCRIPTION_RESOURCE]
       --enable-caching                     Enable internal caching [$ENABLE_CACHING]
       --server.bind=                       Server address (default: :8080) [$SERVER_BIND]
       --server.timeout.read=               Server read timeout (default: 5s) [$SERVER_TIMEOUT_READ]

config/opts.go

@@ -25,8 +25,11 @@ type (
 		}
 
 		Metrics struct {
-			Template string `long:"metrics.template"               env:"METRIC_TEMPLATE"                            description:"Template for metric name"   default:"{name}"`
-			Help     string `long:"metrics.help"                   env:"METRIC_HELP"                                description:"Metric help (with template support)"   default:"Azure monitor insight metric"`
+			Template   string `long:"metrics.template"               env:"METRIC_TEMPLATE"                            description:"Template for metric name"   default:"{name}"`
+			Help       string `long:"metrics.help"                   env:"METRIC_HELP"                                description:"Metric help (with template support)"   default:"Azure monitor insight metric"`
+			Dimensions struct {
+				Lowercase bool `long:"metrics.dimensions.lowercase"   env:"METRIC_DIMENSIONS_LOWERCASE"             description:"Lowercase dimension values"`
+			}
 		}
 
 		// Prober settings

metrics/insights.subscription.go

@@ -38,6 +38,10 @@ func (r *AzureInsightSubscriptionMetricsResult) SendMetricToChannel(channel chan
 								dimensionRowName := to.String(dimensionRow.Name.Value)
 								dimensionRowValue := to.String(dimensionRow.Value)
 
+								if r.prober.settings.DimensionLowercase {
+									dimensionRowValue = strings.ToLower(dimensionRowValue)
+								}
+
 								if strings.EqualFold(dimensionRowName, "microsoft.resourceid") {
 									resourceId = dimensionRowValue
 								} else {

metrics/insights.target.go

@@ -33,7 +33,11 @@ func (r *AzureInsightMetricsResult) SendMetricToChannel(channel chan<- Prometheu
 						dimensions := map[string]string{}
 						if timeseries.Metadatavalues != nil {
 							for _, dimensionRow := range timeseries.Metadatavalues {
-								dimensions[to.String(dimensionRow.Name.Value)] = to.String(dimensionRow.Value)
+								dimensionValue := to.String(dimensionRow.Value)
+								if r.prober.settings.DimensionLowercase {
+									dimensionValue = strings.ToLower(dimensionValue)
+								}
+								dimensions[to.String(dimensionRow.Name.Value)] = dimensionValue
 							}
 						}
 

metrics/settings.go

@@ -39,6 +39,8 @@ type (
 		MetricTemplate string
 		HelpTemplate   string
 
+		DimensionLowercase bool
+
 		// cache
 		Cache *time.Duration
 	}
@@ -67,7 +69,11 @@ func NewRequestMetricSettingsForAzureResourceApi(r *http.Request, opts config.Op
 }
 
 func NewRequestMetricSettings(r *http.Request, opts config.Opts) (RequestMetricSettings, error) {
-	ret := RequestMetricSettings{}
+	ret := RequestMetricSettings{
+		// force lowercasing of dimensions
+		DimensionLowercase: opts.Metrics.Dimensions.Lowercase,
+	}
+
 	params := r.URL.Query()
 
 	// param name