type Counter … type ExemplarAdder … type CounterOpts … type CounterVecOpts … // NewCounter creates a new Counter based on the provided CounterOpts. // // The returned implementation also implements ExemplarAdder. It is safe to // perform the corresponding type assertion. // // The returned implementation tracks the counter value in two separate // variables, a float64 and a uint64. The latter is used to track calls of the // Inc method and calls of the Add method with a value that can be represented // as a uint64. This allows atomic increments of the counter with optimal // performance. (It is common to have an Inc call in very hot execution paths.) // Both internal tracking values are added up in the Write method. This has to // be taken into account when it comes to precision and overflow behavior. func NewCounter(opts CounterOpts) Counter { … } type counter … func (c *counter) Desc() *Desc { … } func (c *counter) Add(v float64) { … } func (c *counter) AddWithExemplar(v float64, e Labels) { … } func (c *counter) Inc() { … } func (c *counter) get() float64 { … } func (c *counter) Write(out *dto.Metric) error { … } func (c *counter) updateExemplar(v float64, l Labels) { … } type CounterVec … // NewCounterVec creates a new CounterVec based on the provided CounterOpts and // partitioned by the given label names. func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec { … } // NewCounterVec creates a new CounterVec based on the provided CounterVecOpts. func (v2) NewCounterVec(opts CounterVecOpts) *CounterVec { … } // GetMetricWithLabelValues returns the Counter for the given slice of label // values (same order as the variable labels in Desc). If that combination of // label values is accessed for the first time, a new Counter is created. // // It is possible to call this method without using the returned Counter to only // create the new Counter but leave it at its starting value 0. See also the // SummaryVec example. // // Keeping the Counter 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 Counter from the CounterVec. In that case, // the Counter will still exist, but it will not be exported anymore, even if a // Counter with the same label values is created later. // // An error is returned if the number of label values is not the same as the // number of variable labels in Desc (minus any curried labels). // // 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). // See also the GaugeVec example. func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) { … } // GetMetricWith returns the Counter for the given Labels map (the label names // must match those of the variable labels in Desc). If that label map is // accessed for the first time, a new Counter is created. Implications of // creating a Counter without using it and keeping the Counter 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 variable labels in Desc (minus any curried labels). // // This method is used for the same purpose as // GetMetricWithLabelValues(...string). See there for pros and cons of the two // methods. func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) { … } // WithLabelValues works as GetMetricWithLabelValues, but panics where // GetMetricWithLabelValues would have returned an error. Not returning an // error allows shortcuts like // // myVec.WithLabelValues("404", "GET").Add(42) func (v *CounterVec) WithLabelValues(lvs ...string) Counter { … } // With works as GetMetricWith, but panics where GetMetricWithLabels would have // returned an error. Not returning an error allows shortcuts like // // myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42) func (v *CounterVec) With(labels Labels) Counter { … } // CurryWith returns a vector curried with the provided labels, i.e. the // returned vector has those labels pre-set for all labeled operations performed // on it. The cardinality of the curried vector is reduced accordingly. The // order of the remaining labels stays the same (just with the curried labels // taken out of the sequence – which is relevant for the // (GetMetric)WithLabelValues methods). It is possible to curry a curried // vector, but only with labels not yet used for currying before. // // The metrics contained in the CounterVec are shared between the curried and // uncurried vectors. They are just accessed differently. Curried and uncurried // vectors behave identically in terms of collection. Only one must be // registered with a given registry (usually the uncurried version). The Reset // method deletes all metrics, even if called on a curried vector. func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) { … } // MustCurryWith works as CurryWith but panics where CurryWith would have // returned an error. func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec { … } type CounterFunc … // NewCounterFunc creates a new CounterFunc based on the provided // CounterOpts. The value reported is determined by calling the given function // from within the Write method. Take into account that metric collection may // happen concurrently. If that results in concurrent calls to Write, like in // the case where a CounterFunc is directly registered with Prometheus, the // provided function must be concurrency-safe. The function should also honor // the contract for a Counter (values only go up, not down), but compliance will // not be checked. // // Check out the ExampleGaugeFunc examples for the similar GaugeFunc. func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc { … }