Interface Metric

prometheus/metric.go:33–59

For convenient use with xxhash. A Metric models a single sample value with its meta data being exported to Prometheus. Implementations of Metric in this package are Gauge, Counter, Histogram, Summary, and Untyped.

// Prometheus. Implementations of Metric in this package are Gauge, Counter,
// Histogram, Summary, and Untyped.
type Metric interface {
	// Desc returns the descriptor for the Metric. This method idempotently
	// returns the same descriptor throughout the lifetime of the
	// Metric. The returned descriptor is immutable by contract. A Metric
	// unable to describe itself must return an invalid descriptor (created
	// with NewInvalidDesc).
	Desc() *Desc
	// Write encodes the Metric into a "Metric" Protocol Buffer data
	// transmission object.
	//
	// Metric implementations must observe concurrency safety as reads of
	// this metric may occur at any time, and any blocking occurs at the
	// expense of total performance of rendering all registered
	// metrics. Ideally, Metric implementations should support concurrent
	// readers.
	//
	// While populating dto.Metric, it is the responsibility of the
	// implementation to ensure validity of the Metric protobuf (like valid
	// UTF-8 strings or syntactically valid metric and label names). It is
	// recommended to sort labels lexicographically. Callers of Write should
	// still make sure of sorting if they depend on it.
	Write(*dto.Metric) error
	// TODO(beorn7): The original rationale of passing in a pre-allocated
	// dto.Metric protobuf to save allocations has disappeared. The
	// signature of this method should be changed to "Write() (*dto.Metric,
	// error)".
}

// Opts bundles the options for creating most Metric types. Each metric
// implementation XXX has its own XXXOpts type, but in most cases, it is just