aboutsummaryrefslogtreecommitdiff
path: root/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/prometheus/client_golang/prometheus/gauge.go')
-rw-r--r--vendor/github.com/prometheus/client_golang/prometheus/gauge.go56
1 files changed, 42 insertions, 14 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
index 9ab5a3d..13064da 100644
--- a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
+++ b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
@@ -63,12 +63,11 @@ func NewGauge(opts GaugeOpts) Gauge {
// (e.g. number of operations queued, partitioned by user and operation
// type). Create instances with NewGaugeVec.
type GaugeVec struct {
- *MetricVec
+ *metricVec
}
// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
-// partitioned by the given label names. At least one label name must be
-// provided.
+// partitioned by the given label names.
func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
desc := NewDesc(
BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
@@ -77,28 +76,57 @@ func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
opts.ConstLabels,
)
return &GaugeVec{
- MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+ metricVec: newMetricVec(desc, func(lvs ...string) Metric {
return newValue(desc, GaugeValue, 0, lvs...)
}),
}
}
-// GetMetricWithLabelValues replaces the method of the same name in
-// MetricVec. The difference is that this method returns a Gauge and not a
-// Metric so that no type conversion is required.
+// GetMetricWithLabelValues returns the Gauge 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 Gauge is created.
+//
+// It is possible to call this method without using the returned Gauge to only
+// create the new Gauge but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Gauge 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 Gauge from the GaugeVec. In that case, the
+// Gauge will still exist, but it will not be exported anymore, even if a
+// Gauge 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 GetMetricWith(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).
func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
- metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+ metric, err := m.metricVec.getMetricWithLabelValues(lvs...)
if metric != nil {
return metric.(Gauge), err
}
return nil, err
}
-// GetMetricWith replaces the method of the same name in MetricVec. The
-// difference is that this method returns a Gauge and not a Metric so that no
-// type conversion is required.
+// GetMetricWith returns the Gauge 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 Gauge is created. Implications of
+// creating a Gauge without using it and keeping the Gauge 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
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
- metric, err := m.MetricVec.GetMetricWith(labels)
+ metric, err := m.metricVec.getMetricWith(labels)
if metric != nil {
return metric.(Gauge), err
}
@@ -110,14 +138,14 @@ func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
// error, WithLabelValues allows shortcuts like
// myVec.WithLabelValues("404", "GET").Add(42)
func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
- return m.MetricVec.WithLabelValues(lvs...).(Gauge)
+ return m.metricVec.withLabelValues(lvs...).(Gauge)
}
// With works as GetMetricWith, but panics where GetMetricWithLabels would have
// returned an error. By not returning an error, With allows shortcuts like
// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
func (m *GaugeVec) With(labels Labels) Gauge {
- return m.MetricVec.With(labels).(Gauge)
+ return m.metricVec.with(labels).(Gauge)
}
// GaugeFunc is a Gauge whose value is determined at collect time by calling a