Struct prometheus::core::MetricVec

pub struct MetricVec<T: MetricVecBuilder> { /* fields omitted */ }

A Collector to bundle metrics of the same name that differ in their label values. It is usually not used directly but as a building block for implementations of vectors of a given metric type. GaugeVec and CounterVec are examples already provided in this package.

Methods

impl<T: MetricVecBuilder> MetricVec<T>

pub fn create(     metric_type: MetricType,     new_metric: T,     opts: T::P ) -> Result<MetricVec<T>>

create creates a MetricVec with description desc, a metric type metric_type and a MetricVecBuilder new_metric.

pub fn get_metric_with_label_values(&self, vals: &[&str]) -> Result<T::M>

get_metric_with_label_values returns the Metric for the given slice of label values (same order as the VariableLabels in Desc). If that combination of label values is accessed for the first time, a new Metric is created.

It is possible to call this method without using the returned Metric to only create the new Metric but leave it at its start value (e.g. a Histogram without any observations).

Keeping the Metric for later use is possible (and should be considered if performance is critical), but keep in mind that Reset, DeleteLabelValues and Delete can be used to delete the Metric from the MetricVec. In thatcase, the Metric will still exist, but it will not be exported anymore, even if a Metric with the same label values is created later. See also the CounterVec example.

An error is returned if the number of label values is not the same as the number of VariableLabels in Desc.

Note that for more than one label value, this method is prone to mistakes caused by an incorrect order of arguments. Consider get_metric_with(labels) as an alternative to avoid that type of mistake. For higher label numbers, the latter has a much more readable (albeit more verbose) syntax, but it comes with a performance overhead (for creating and processing the Labels map).

pub fn get_metric_with(&self, labels: &HashMap<&str, &str>) -> Result<T::M>

get_metric_with returns the Metric for the given Labels map (the label names must match those of the VariableLabels in Desc). If that label map is accessed for the first time, a new Metric is created. Implications of creating a Metric without using it and keeping the Metric for later use are the same as for GetMetricWithLabelValues.

An error is returned if the number and names of the Labels are inconsistent with those of the VariableLabels in Desc.

This method is used for the same purpose as get_metric_with_label_values. See there for pros and cons of the two methods.

pub fn with_label_values(&self, vals: &[&str]) -> T::M

with_label_values works as get_metric_with_label_values, but panics if an error occurs. The method allows neat syntax like: httpReqs.with_label_values("404", "POST").inc()

pub fn with(&self, labels: &HashMap<&str, &str>) -> T::M

with works as get_metric_with, but panics if an error occurs. The method allows neat syntax like: httpReqs.with(Labels{"status":"404", "method":"POST"}).inc()

pub fn remove_label_values(&self, vals: &[&str]) -> Result<()>

remove_label_values removes the metric where the variable labels are the same as those passed in as labels (same order as the VariableLabels in Desc). It returns true if a metric was deleted.

It returns an error if the number of label values is not the same as the number of VariableLabels in Desc.

Note that for more than one label value, this method is prone to mistakes caused by an incorrect order of arguments. Consider delete(labels) as an alternative to avoid that type of mistake. For higher label numbers, the latter has a much more readable (albeit more verbose) syntax, but it comes with a performance overhead (for creating and processing the Labels map).

pub fn remove(&self, labels: &HashMap<&str, &str>) -> Result<()>

remove removes the metric where the variable labels are the same as those passed in as labels. It returns true if a metric was deleted.

It returns an error if the number and names of the Labels are inconsistent with those of the VariableLabels in the Desc of the MetricVec.

This method is used for the same purpose as delete_label_values. See there for pros and cons of the two methods.

pub fn reset(&self)

reset deletes all metrics in this vector.

Trait Implementations

impl<T: MetricVecBuilder> Collector for MetricVec<T>

fn desc(&self) -> Vec<&Desc>

Return descriptors for metrics.

fn collect(&self) -> Vec<MetricFamily>

Collect metrics.

impl<T: Clone + MetricVecBuilder> Clone for MetricVec<T>

fn clone(&self) -> MetricVec<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.