metrics

var (
	TotalQueries = prometheus.NewCounter(
		prometheus.CounterOpts{
			Name: "total_queries",
			Help: "Total number of DNS queries received.",
		},
	)

	CacheHits = prometheus.NewCounter(
		prometheus.CounterOpts{
			Name: "cache_hits",
			Help: "Total number of DNS queries answered from cache.",
		},
	)

	CacheMisses = prometheus.NewCounter(
		prometheus.CounterOpts{
			Name: "cache_misses",
			Help: "Total number of DNS queries not answered from cache.",
		},
	)

	CacheSize = prometheus.NewGauge(
		prometheus.GaugeOpts{
			Name: "cache_size",
			Help: "Current number of records in cache.",
		},
	)

	BlocklistDuration = prometheus.NewHistogram(
		prometheus.HistogramOpts{
			Name: "blocklist_duration",
			Help: "Histogram of blocklist query durations.",
			Buckets: []float64{
				0.0000001,
				0.0000002,
				0.0000003,
				0.0000004,
				0.0000005,
				0.0000006,
				0.0000007,
				0.0000008,
				0.0000009,
			},
		},
	)

	BlockedCount = prometheus.NewCounter(
		prometheus.CounterOpts{
			Name: "blocked_count",
			Help: "Total number of DNS queries blocked by the blocklist.",
		},
	)

	CacheDuration = prometheus.NewHistogram(
		prometheus.HistogramOpts{
			Name:    "cache_duration",
			Help:    "Histogram of cache query durations.",
			Buckets: []float64{0.0000001, 0.000001, 0.00001, 0.0001, 0.001},
		},
	)

	RequestDuration = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Name:    "request_duration",
			Help:    "Duration of request starting from networking layer to response.",
			Buckets: []float64{0.01, 0.1, 0.25},
		},
		[]string{"protocol"},
	)

	ResolutionDuration = prometheus.NewHistogram(
		prometheus.HistogramOpts{
			Name:    "resolution_duration",
			Help:    "Time taken to process a request after handoff from networking layer.",
			Buckets: []float64{0.01, 0.1, 0.25},
		},
	)

	UpstreamDuration = prometheus.NewHistogram(
		prometheus.HistogramOpts{
			Name:    "upstream_duration",
			Help:    "Time taken to query upstream DNS server.",
			Buckets: []float64{0.01, 0.02, 0.03, 0.04, 0.05},
		},
	)

	UpstreamRTT = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Name:    "upstream_rtt",
			Help:    "Round trip time to upstream DNS server.",
			Buckets: []float64{0.01, 0.02, 0.03, 0.04, 0.05},
		},
		[]string{"server"},
	)
)