Fix metric name validation to use correct validation scheme method (cortexproject#7087)

Signed-off-by: Anna Tran <[email protected]>

Author: anna-tran

CHANGELOG.md

@@ -109,6 +109,7 @@
 * [BUGFIX] Distributor: Fix `/distributor/all_user_stats` api to work during rolling updates on ingesters. #7026
 * [BUGFIX] Runtime-config: Fix panic when the runtime config is `null`. #7062
 * [BUGFIX] Scheduler: Avoid all queriers reserved for prioritized requests. #7057
+* [BUGFIX] Fix bug where validating metric names uses the wrong validation logic. #7086
 
 ## 1.19.1 2025-09-20
 

pkg/util/validation/validate.go

@@ -285,7 +285,7 @@ func ValidateLabels(validateMetrics *ValidateMetrics, limits *Limits, userID str
 			return newNoMetricNameError()
 		}
 
-		if !nameValidationScheme.IsValidLabelName(unsafeMetricName) {
+		if !nameValidationScheme.IsValidMetricName(unsafeMetricName) {
 			validateMetrics.DiscardedSamples.WithLabelValues(invalidMetricName, userID).Inc()
 			return newInvalidMetricNameError(unsafeMetricName)
 		}

pkg/util/validation/validate_test.go

@@ -134,7 +134,7 @@ func TestValidateLabels(t *testing.T) {
 			}, "foo "),
 		},
 		{
-			map[model.LabelName]model.LabelValue{model.MetricNameLabel: "valid"},
+			map[model.LabelName]model.LabelValue{model.MetricNameLabel: "valid:name"},
 			false,
 			nil,
 		},
@@ -201,7 +201,7 @@ func TestValidateLabels(t *testing.T) {
 			# HELP cortex_label_size_bytes The combined size in bytes of all labels and label values for a time series.
 			# TYPE cortex_label_size_bytes histogram
 			cortex_label_size_bytes_bucket{user="testUser",le="+Inf"} 3
-			cortex_label_size_bytes_sum{user="testUser"} 148
+			cortex_label_size_bytes_sum{user="testUser"} 153
 			cortex_label_size_bytes_count{user="testUser"} 3
 	`), "cortex_label_size_bytes"))