Files
glance/internal/glance/widget-dns-stats.go
Svilen Markov ac7f3805d4 Add custom unmarshalling for pihole queries stats
+ hide-graph and hide-top-domains options for DNS stats widget
2024-12-28 14:17:48 +00:00

382 lines
9.9 KiB
Go

package glance
import (
"context"
"encoding/json"
"errors"
"html/template"
"log/slog"
"net/http"
"sort"
"strings"
"time"
)
var dnsStatsWidgetTemplate = mustParseTemplate("dns-stats.html", "widget-base.html")
type dnsStatsWidget struct {
widgetBase `yaml:",inline"`
TimeLabels [8]string `yaml:"-"`
Stats *dnsStats `yaml:"-"`
HourFormat string `yaml:"hour-format"`
HideGraph bool `yaml:"hide-graph"`
HideTopDomains bool `yaml:"hide-top-domains"`
Service string `yaml:"service"`
AllowInsecure bool `yaml:"allow-insecure"`
URL string `yaml:"url"`
Token string `yaml:"token"`
Username string `yaml:"username"`
Password string `yaml:"password"`
}
func makeDNSWidgetTimeLabels(format string) [8]string {
now := time.Now()
var labels [8]string
for h := 24; h > 0; h -= 3 {
labels[7-(h/3-1)] = strings.ToLower(now.Add(-time.Duration(h) * time.Hour).Format(format))
}
return labels
}
func (widget *dnsStatsWidget) initialize() error {
widget.
withTitle("DNS Stats").
withTitleURL(string(widget.URL)).
withCacheDuration(10 * time.Minute)
if widget.Service != "adguard" && widget.Service != "pihole" {
return errors.New("service must be either 'adguard' or 'pihole'")
}
return nil
}
func (widget *dnsStatsWidget) update(ctx context.Context) {
var stats *dnsStats
var err error
if widget.Service == "adguard" {
stats, err = fetchAdguardStats(widget.URL, widget.AllowInsecure, widget.Username, widget.Password, widget.HideGraph)
} else {
stats, err = fetchPiholeStats(widget.URL, widget.AllowInsecure, widget.Token, widget.HideGraph)
}
if !widget.canContinueUpdateAfterHandlingErr(err) {
return
}
if widget.HourFormat == "24h" {
widget.TimeLabels = makeDNSWidgetTimeLabels("15:00")
} else {
widget.TimeLabels = makeDNSWidgetTimeLabels("3PM")
}
widget.Stats = stats
}
func (widget *dnsStatsWidget) Render() template.HTML {
return widget.renderTemplate(widget, dnsStatsWidgetTemplate)
}
type dnsStats struct {
TotalQueries int
BlockedQueries int
BlockedPercent int
ResponseTime int
DomainsBlocked int
Series [8]dnsStatsSeries
TopBlockedDomains []dnsStatsBlockedDomain
}
type dnsStatsSeries struct {
Queries int
Blocked int
PercentTotal int
PercentBlocked int
}
type dnsStatsBlockedDomain struct {
Domain string
PercentBlocked int
}
type adguardStatsResponse struct {
TotalQueries int `json:"num_dns_queries"`
QueriesSeries []int `json:"dns_queries"`
BlockedQueries int `json:"num_blocked_filtering"`
BlockedSeries []int `json:"blocked_filtering"`
ResponseTime float64 `json:"avg_processing_time"`
TopBlockedDomains []map[string]int `json:"top_blocked_domains"`
}
func fetchAdguardStats(instanceURL string, allowInsecure bool, username, password string, noGraph bool) (*dnsStats, error) {
requestURL := strings.TrimRight(instanceURL, "/") + "/control/stats"
request, err := http.NewRequest("GET", requestURL, nil)
if err != nil {
return nil, err
}
request.SetBasicAuth(username, password)
var client requestDoer
if !allowInsecure {
client = defaultHTTPClient
} else {
client = defaultInsecureHTTPClient
}
responseJson, err := decodeJsonFromRequest[adguardStatsResponse](client, request)
if err != nil {
return nil, err
}
var topBlockedDomainsCount = min(len(responseJson.TopBlockedDomains), 5)
stats := &dnsStats{
TotalQueries: responseJson.TotalQueries,
BlockedQueries: responseJson.BlockedQueries,
ResponseTime: int(responseJson.ResponseTime * 1000),
TopBlockedDomains: make([]dnsStatsBlockedDomain, 0, topBlockedDomainsCount),
}
if stats.TotalQueries <= 0 {
return stats, nil
}
stats.BlockedPercent = int(float64(responseJson.BlockedQueries) / float64(responseJson.TotalQueries) * 100)
for i := 0; i < topBlockedDomainsCount; i++ {
domain := responseJson.TopBlockedDomains[i]
var firstDomain string
for k := range domain {
firstDomain = k
break
}
if firstDomain == "" {
continue
}
stats.TopBlockedDomains = append(stats.TopBlockedDomains, dnsStatsBlockedDomain{
Domain: firstDomain,
})
if stats.BlockedQueries > 0 {
stats.TopBlockedDomains[i].PercentBlocked = int(float64(domain[firstDomain]) / float64(responseJson.BlockedQueries) * 100)
}
}
if noGraph {
return stats, nil
}
queriesSeries := responseJson.QueriesSeries
blockedSeries := responseJson.BlockedSeries
const bars = 8
const hoursSpan = 24
const hoursPerBar int = hoursSpan / bars
if len(queriesSeries) > hoursSpan {
queriesSeries = queriesSeries[len(queriesSeries)-hoursSpan:]
} else if len(queriesSeries) < hoursSpan {
queriesSeries = append(make([]int, hoursSpan-len(queriesSeries)), queriesSeries...)
}
if len(blockedSeries) > hoursSpan {
blockedSeries = blockedSeries[len(blockedSeries)-hoursSpan:]
} else if len(blockedSeries) < hoursSpan {
blockedSeries = append(make([]int, hoursSpan-len(blockedSeries)), blockedSeries...)
}
maxQueriesInSeries := 0
for i := 0; i < bars; i++ {
queries := 0
blocked := 0
for j := 0; j < hoursPerBar; j++ {
queries += queriesSeries[i*hoursPerBar+j]
blocked += blockedSeries[i*hoursPerBar+j]
}
stats.Series[i] = dnsStatsSeries{
Queries: queries,
Blocked: blocked,
}
if queries > 0 {
stats.Series[i].PercentBlocked = int(float64(blocked) / float64(queries) * 100)
}
if queries > maxQueriesInSeries {
maxQueriesInSeries = queries
}
}
for i := 0; i < bars; i++ {
stats.Series[i].PercentTotal = int(float64(stats.Series[i].Queries) / float64(maxQueriesInSeries) * 100)
}
return stats, nil
}
type piholeStatsResponse struct {
TotalQueries int `json:"dns_queries_today"`
QueriesSeries piholeQueriesSeries `json:"domains_over_time"`
BlockedQueries int `json:"ads_blocked_today"`
BlockedSeries map[int64]int `json:"ads_over_time"`
BlockedPercentage float64 `json:"ads_percentage_today"`
TopBlockedDomains piholeTopBlockedDomains `json:"top_ads"`
DomainsBlocked int `json:"domains_being_blocked"`
}
// If the user has query logging disabled it's possible for domains_over_time to be returned as an
// empty array rather than a map which will prevent unmashalling the rest of the data so we use
// custom unmarshal behavior to fallback to an empty map.
// See https://github.com/glanceapp/glance/issues/289
type piholeQueriesSeries map[int64]int
func (p *piholeQueriesSeries) UnmarshalJSON(data []byte) error {
temp := make(map[int64]int)
err := json.Unmarshal(data, &temp)
if err != nil {
*p = make(piholeQueriesSeries)
} else {
*p = temp
}
return nil
}
// If user has some level of privacy enabled on Pihole, `json:"top_ads"` is an empty array
// Use custom unmarshal behavior to avoid not getting the rest of the valid data when unmarshalling
type piholeTopBlockedDomains map[string]int
func (p *piholeTopBlockedDomains) UnmarshalJSON(data []byte) error {
// NOTE: do not change to piholeTopBlockedDomains type here or it will cause a stack overflow
// because of the UnmarshalJSON method getting called recursively
temp := make(map[string]int)
err := json.Unmarshal(data, &temp)
if err != nil {
*p = make(piholeTopBlockedDomains)
} else {
*p = temp
}
return nil
}
func fetchPiholeStats(instanceURL string, allowInsecure bool, token string, noGraph bool) (*dnsStats, error) {
if token == "" {
return nil, errors.New("missing API token")
}
requestURL := strings.TrimRight(instanceURL, "/") +
"/admin/api.php?summaryRaw&topItems&overTimeData10mins&auth=" + token
request, err := http.NewRequest("GET", requestURL, nil)
if err != nil {
return nil, err
}
var client requestDoer
if !allowInsecure {
client = defaultHTTPClient
} else {
client = defaultInsecureHTTPClient
}
responseJson, err := decodeJsonFromRequest[piholeStatsResponse](client, request)
if err != nil {
return nil, err
}
stats := &dnsStats{
TotalQueries: responseJson.TotalQueries,
BlockedQueries: responseJson.BlockedQueries,
BlockedPercent: int(responseJson.BlockedPercentage),
DomainsBlocked: responseJson.DomainsBlocked,
}
if len(responseJson.TopBlockedDomains) > 0 {
domains := make([]dnsStatsBlockedDomain, 0, len(responseJson.TopBlockedDomains))
for domain, count := range responseJson.TopBlockedDomains {
domains = append(domains, dnsStatsBlockedDomain{
Domain: domain,
PercentBlocked: int(float64(count) / float64(responseJson.BlockedQueries) * 100),
})
}
sort.Slice(domains, func(a, b int) bool {
return domains[a].PercentBlocked > domains[b].PercentBlocked
})
stats.TopBlockedDomains = domains[:min(len(domains), 5)]
}
if noGraph {
return stats, nil
}
// Pihole _should_ return data for the last 24 hours in a 10 minute interval, 6*24 = 144
if len(responseJson.QueriesSeries) != 144 || len(responseJson.BlockedSeries) != 144 {
slog.Warn(
"DNS stats for pihole: did not get expected 144 data points",
"len(queries)", len(responseJson.QueriesSeries),
"len(blocked)", len(responseJson.BlockedSeries),
)
return stats, nil
}
var lowestTimestamp int64 = 0
for timestamp := range responseJson.QueriesSeries {
if lowestTimestamp == 0 || timestamp < lowestTimestamp {
lowestTimestamp = timestamp
}
}
maxQueriesInSeries := 0
for i := 0; i < 8; i++ {
queries := 0
blocked := 0
for j := 0; j < 18; j++ {
index := lowestTimestamp + int64(i*10800+j*600)
queries += responseJson.QueriesSeries[index]
blocked += responseJson.BlockedSeries[index]
}
if queries > maxQueriesInSeries {
maxQueriesInSeries = queries
}
stats.Series[i] = dnsStatsSeries{
Queries: queries,
Blocked: blocked,
}
if queries > 0 {
stats.Series[i].PercentBlocked = int(float64(blocked) / float64(queries) * 100)
}
}
for i := 0; i < 8; i++ {
stats.Series[i].PercentTotal = int(float64(stats.Series[i].Queries) / float64(maxQueriesInSeries) * 100)
}
return stats, nil
}