instrumented_http

var (
	// RequestDurationSeconds is a Prometheus summary to collect request times.
	RequestDurationSeconds = prometheus.NewSummaryVec(
		prometheus.SummaryOpts{
			Name:        "request_duration_seconds",
			Help:        "The HTTP request latencies in seconds.",
			Subsystem:   "http",
			ConstLabels: prometheus.Labels{"handler": handlerName},
			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
		},
		[]string{"scheme", "host", "path", "query", "method", "status"},
	)

	// EliminatingProcessor is a callback that returns a blank string on any input.
	EliminatingProcessor = func(_ string) string { return "" }
	// IdentityProcessor is callback that returns whatever is passed to it.
	IdentityProcessor = func(input string) string { return input }
	// LastPathElementProcessor is callback that returns the last element of a URL path.
	LastPathElementProcessor = func(path string) string {
		parts := strings.Split(path, "/")
		return parts[len(parts)-1]
	}
)