labels method
Create a Child
metric and assign the labelValues
.
The size of the labelValues
has to match the labelNames of the metric.
Implementation
Child labels(List<String> labelValues) {
if (labelValues.length != labelNames.length) {
throw ArgumentError.value(
labelValues, 'labelValues', 'Length must match label names.');
}
return _children.putIfAbsent(List.unmodifiable(labelValues), _createChild);
}