metrics: make LabelFromKey optional / omitempty

Author: chrischdi

pkg/metrics/internal/config/config_metrics_types.go

@@ -32,7 +32,7 @@ type MetricGauge struct {
 	// ValueFrom is the path to a numeric field under Path that will be the metric value.
 	ValueFrom []string `yaml:"valueFrom" json:"valueFrom"`
 	// LabelFromKey adds a label with the given name if Path is an object. The label value will be the object key.
-	LabelFromKey string `yaml:"labelFromKey" json:"labelFromKey"`
+	LabelFromKey string `yaml:"labelFromKey,omitempty" json:"labelFromKey,omitempty"`
 	// NilIsZero indicates that if a value is nil it will be treated as zero value.
 	NilIsZero bool `yaml:"nilIsZero" json:"nilIsZero"`
 }
@@ -42,7 +42,7 @@ type MetricGauge struct {
 type MetricInfo struct {
 	MetricMeta `yaml:",inline" json:",inline"`
 	// LabelFromKey adds a label with the given name if Path is an object. The label value will be the object key.
-	LabelFromKey string `yaml:"labelFromKey" json:"labelFromKey"`
+	LabelFromKey string `yaml:"labelFromKey,omitempty" json:"labelFromKey,omitempty"`
 }
 
 // MetricStateSet is a metric which represent a series of related boolean values, also called a bitset.

pkg/metrics/internal/config/doc.go

@@ -35,4 +35,6 @@ limitations under the License.
 // * Rename the package to `config`.
 // * Add `omitempty` to:
 //   - `MetricMeta.LabelsFromPath
+//   - `MetricGauge.LabelFromkey`
+//   - `MetricInfo.LabelFromkey`
 package config