AdGuardHome/dnsforward/stats.go

356 lines
10 KiB
Go

package dnsforward
import (
"fmt"
"sync"
"time"
"github.com/AdguardTeam/AdGuardHome/dnsfilter"
)
// how far back to keep the stats
const statsHistoryElements = 60 + 1 // +1 for calculating delta
// entries for single time period (for example all per-second entries)
type statsEntries map[string][statsHistoryElements]float64
// each periodic stat is a map of arrays
type periodicStats struct {
entries statsEntries
period time.Duration // how long one entry lasts
lastRotate time.Time // last time this data was rotated
sync.RWMutex
}
// stats is the DNS server historical statistics
type stats struct {
perSecond periodicStats
perMinute periodicStats
perHour periodicStats
perDay periodicStats
requests *counter // total number of requests
filtered *counter // total number of filtered requests
filteredLists *counter // total number of requests blocked by filter lists
filteredSafebrowsing *counter // total number of requests blocked by safebrowsing
filteredParental *counter // total number of requests blocked by the parental control
whitelisted *counter // total number of requests whitelisted by filter lists
safesearch *counter // total number of requests for which safe search rules were applied
errorsTotal *counter // total number of errors
elapsedTime *histogram // requests duration histogram
}
// initializes an empty stats structure
func newStats() *stats {
s := &stats{
requests: newDNSCounter("requests_total"),
filtered: newDNSCounter("filtered_total"),
filteredLists: newDNSCounter("filtered_lists_total"),
filteredSafebrowsing: newDNSCounter("filtered_safebrowsing_total"),
filteredParental: newDNSCounter("filtered_parental_total"),
whitelisted: newDNSCounter("whitelisted_total"),
safesearch: newDNSCounter("safesearch_total"),
errorsTotal: newDNSCounter("errors_total"),
elapsedTime: newDNSHistogram("request_duration"),
}
// Initializes empty per-sec/minute/hour/day stats
s.purgeStats()
return s
}
func initPeriodicStats(periodic *periodicStats, period time.Duration) {
periodic.Lock()
periodic.entries = statsEntries{}
periodic.lastRotate = time.Now()
periodic.period = period
periodic.Unlock()
}
func (s *stats) purgeStats() {
initPeriodicStats(&s.perSecond, time.Second)
initPeriodicStats(&s.perMinute, time.Minute)
initPeriodicStats(&s.perHour, time.Hour)
initPeriodicStats(&s.perDay, time.Hour*24)
}
func (p *periodicStats) Inc(name string, when time.Time) {
// calculate how many periods ago this happened
elapsed := int64(time.Since(when) / p.period)
// log.Tracef("%s: %v as %v -> [%v]", name, time.Since(when), p.period, elapsed)
if elapsed >= statsHistoryElements {
return // outside of our timeframe
}
p.Lock()
currentValues := p.entries[name]
currentValues[elapsed]++
p.entries[name] = currentValues
p.Unlock()
}
func (p *periodicStats) Observe(name string, when time.Time, value float64) {
// calculate how many periods ago this happened
elapsed := int64(time.Since(when) / p.period)
// log.Tracef("%s: %v as %v -> [%v]", name, time.Since(when), p.period, elapsed)
if elapsed >= statsHistoryElements {
return // outside of our timeframe
}
p.Lock()
{
countname := name + "_count"
currentValues := p.entries[countname]
v := currentValues[elapsed]
// log.Tracef("Will change p.entries[%s][%d] from %v to %v", countname, elapsed, value, value+1)
v++
currentValues[elapsed] = v
p.entries[countname] = currentValues
}
{
totalname := name + "_sum"
currentValues := p.entries[totalname]
currentValues[elapsed] += value
p.entries[totalname] = currentValues
}
p.Unlock()
}
func (p *periodicStats) statsRotate(now time.Time) {
p.Lock()
rotations := int64(now.Sub(p.lastRotate) / p.period)
if rotations > statsHistoryElements {
rotations = statsHistoryElements
}
// calculate how many times we should rotate
for r := int64(0); r < rotations; r++ {
for key, values := range p.entries {
newValues := [statsHistoryElements]float64{}
for i := 1; i < len(values); i++ {
newValues[i] = values[i-1]
}
p.entries[key] = newValues
}
}
if rotations > 0 {
p.lastRotate = now
}
p.Unlock()
}
func (s *stats) statsRotator() {
for range time.Tick(time.Second) {
now := time.Now()
s.perSecond.statsRotate(now)
s.perMinute.statsRotate(now)
s.perHour.statsRotate(now)
s.perDay.statsRotate(now)
}
}
// counter that wraps around prometheus Counter but also adds to periodic stats
type counter struct {
name string // used as key in periodic stats
value int64
sync.Mutex
}
func newDNSCounter(name string) *counter {
// log.Tracef("called")
return &counter{
name: name,
}
}
func (s *stats) incWithTime(c *counter, when time.Time) {
s.perSecond.Inc(c.name, when)
s.perMinute.Inc(c.name, when)
s.perHour.Inc(c.name, when)
s.perDay.Inc(c.name, when)
c.Lock()
c.value++
c.Unlock()
}
type histogram struct {
name string // used as key in periodic stats
count int64
total float64
sync.Mutex
}
func newDNSHistogram(name string) *histogram {
return &histogram{
name: name,
}
}
func (s *stats) observeWithTime(h *histogram, value float64, when time.Time) {
s.perSecond.Observe(h.name, when, value)
s.perMinute.Observe(h.name, when, value)
s.perHour.Observe(h.name, when, value)
s.perDay.Observe(h.name, when, value)
h.Lock()
h.count++
h.total += value
h.Unlock()
}
// -----
// stats
// -----
func (s *stats) incrementCounters(entry *logEntry) {
s.incWithTime(s.requests, entry.Time)
if entry.Result.IsFiltered {
s.incWithTime(s.filtered, entry.Time)
}
switch entry.Result.Reason {
case dnsfilter.NotFilteredWhiteList:
s.incWithTime(s.whitelisted, entry.Time)
case dnsfilter.NotFilteredError:
s.incWithTime(s.errorsTotal, entry.Time)
case dnsfilter.FilteredBlackList:
s.incWithTime(s.filteredLists, entry.Time)
case dnsfilter.FilteredSafeBrowsing:
s.incWithTime(s.filteredSafebrowsing, entry.Time)
case dnsfilter.FilteredParental:
s.incWithTime(s.filteredParental, entry.Time)
case dnsfilter.FilteredInvalid:
// do nothing
case dnsfilter.FilteredSafeSearch:
s.incWithTime(s.safesearch, entry.Time)
}
s.observeWithTime(s.elapsedTime, entry.Elapsed.Seconds(), entry.Time)
}
// getAggregatedStats returns aggregated stats data for the 24 hours
func (s *stats) getAggregatedStats() map[string]interface{} {
const numHours = 24
historical := s.generateMapFromStats(&s.perHour, 0, numHours)
// sum them up
summed := map[string]interface{}{}
for key, values := range historical {
summedValue := 0.0
floats, ok := values.([]float64)
if !ok {
continue
}
for _, v := range floats {
summedValue += v
}
summed[key] = summedValue
}
// don't forget to divide by number of elements in returned slice
if val, ok := summed["avg_processing_time"]; ok {
if flval, flok := val.(float64); flok {
flval /= numHours
summed["avg_processing_time"] = flval
}
}
summed["stats_period"] = "24 hours"
return summed
}
func (s *stats) generateMapFromStats(stats *periodicStats, start int, end int) map[string]interface{} {
stats.RLock()
defer stats.RUnlock()
// clamp
start = clamp(start, 0, statsHistoryElements)
end = clamp(end, 0, statsHistoryElements)
avgProcessingTime := make([]float64, 0)
count := getReversedSlice(stats.entries[s.elapsedTime.name+"_count"], start, end)
sum := getReversedSlice(stats.entries[s.elapsedTime.name+"_sum"], start, end)
for i := 0; i < len(count); i++ {
var avg float64
if count[i] != 0 {
avg = sum[i] / count[i]
avg *= 1000
}
avgProcessingTime = append(avgProcessingTime, avg)
}
result := map[string]interface{}{
"dns_queries": getReversedSlice(stats.entries[s.requests.name], start, end),
"blocked_filtering": getReversedSlice(stats.entries[s.filtered.name], start, end),
"replaced_safebrowsing": getReversedSlice(stats.entries[s.filteredSafebrowsing.name], start, end),
"replaced_safesearch": getReversedSlice(stats.entries[s.safesearch.name], start, end),
"replaced_parental": getReversedSlice(stats.entries[s.filteredParental.name], start, end),
"avg_processing_time": avgProcessingTime,
}
return result
}
// getStatsHistory gets stats history aggregated by the specified time unit
// timeUnit is either time.Second, time.Minute, time.Hour, or 24*time.Hour
// start is start of the time range
// end is end of the time range
// returns nil if time unit is not supported
func (s *stats) getStatsHistory(timeUnit time.Duration, startTime time.Time, endTime time.Time) (map[string]interface{}, error) {
var stats *periodicStats
switch timeUnit {
case time.Second:
stats = &s.perSecond
case time.Minute:
stats = &s.perMinute
case time.Hour:
stats = &s.perHour
case 24 * time.Hour:
stats = &s.perDay
}
if stats == nil {
return nil, fmt.Errorf("unsupported time unit: %v", timeUnit)
}
now := time.Now()
// check if start and time times are within supported time range
timeRange := timeUnit * statsHistoryElements
if startTime.Add(timeRange).Before(now) {
return nil, fmt.Errorf("start_time parameter is outside of supported range: %s", startTime.String())
}
if endTime.Add(timeRange).Before(now) {
return nil, fmt.Errorf("end_time parameter is outside of supported range: %s", startTime.String())
}
// calculate start and end of our array
// basically it's how many hours/minutes/etc have passed since now
start := int(now.Sub(endTime) / timeUnit)
end := int(now.Sub(startTime) / timeUnit)
// swap them around if they're inverted
if start > end {
start, end = end, start
}
return s.generateMapFromStats(stats, start, end), nil
}
func clamp(value, low, high int) int {
if value < low {
return low
}
if value > high {
return high
}
return value
}
// --------------------------
// helper functions for stats
// --------------------------
func getReversedSlice(input [statsHistoryElements]float64, start int, end int) []float64 {
output := make([]float64, 0)
for i := start; i <= end; i++ {
output = append([]float64{input[i]}, output...)
}
return output
}