Querylog -- Implement file writing and update /querylog handler for changed structures.

This commit is contained in:
Eugene Bujak 2018-10-07 00:51:44 +03:00
parent 16fd1359cd
commit 2c33905a79
4 changed files with 255 additions and 32 deletions

View File

@ -219,6 +219,7 @@ func setup(c *caddy.Controller) error {
return nil
})
c.OnShutdown(p.onShutdown)
c.OnFinalShutdown(p.onFinalShutdown)
return nil
}
@ -250,6 +251,15 @@ func (p *plug) onShutdown() error {
return nil
}
func (p *plug) onFinalShutdown() error {
err := flushToFile(logBuffer)
if err != nil {
log.Printf("failed to flush to file: %s", err)
return err
}
return nil
}
type statsFunc func(ch interface{}, name string, text string, value float64, valueType prometheus.ValueType)
func doDesc(ch interface{}, name string, text string, value float64, valueType prometheus.ValueType) {

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@ -5,6 +5,8 @@ import (
"fmt"
"log"
"net/http"
"os"
"path"
"runtime"
"strconv"
"strings"
@ -13,45 +15,93 @@ import (
"github.com/AdguardTeam/AdguardDNS/dnsfilter"
"github.com/coredns/coredns/plugin/pkg/response"
"github.com/miekg/dns"
"github.com/zfjagann/golang-ring"
)
const logBufferCap = 10000
const (
logBufferCap = 1000 // maximum capacity of logBuffer before it's flushed to disk
queryLogAPI = 1000 // maximum API response for /querylog
)
var logBuffer = ring.Ring{}
var (
logBuffer []logEntry
)
type logEntry struct {
Question *dns.Msg
Answer *dns.Msg
Question []byte
Answer []byte
Result dnsfilter.Result
Time time.Time
Elapsed time.Duration
IP string
}
func init() {
logBuffer.SetCapacity(logBufferCap)
func logRequest(question *dns.Msg, answer *dns.Msg, result dnsfilter.Result, elapsed time.Duration, ip string) {
var q []byte
var a []byte
var err error
if question != nil {
q, err = question.Pack()
if err != nil {
log.Printf("failed to pack question for querylog: %s", err)
return
}
}
if answer != nil {
a, err = answer.Pack()
if err != nil {
log.Printf("failed to pack answer for querylog: %s", err)
return
}
}
func logRequest(question *dns.Msg, answer *dns.Msg, result dnsfilter.Result, elapsed time.Duration, ip string) {
entry := logEntry{
Question: question,
Answer: answer,
Question: q,
Answer: a,
Result: result,
Time: time.Now(),
Elapsed: elapsed,
IP: ip,
}
logBuffer.Enqueue(entry)
var flushBuffer []logEntry
logBuffer = append(logBuffer, entry)
if len(logBuffer) >= logBufferCap {
flushBuffer = logBuffer
logBuffer = nil
}
if len(flushBuffer) > 0 {
// write to file
// do it in separate goroutine -- we are stalling DNS response this whole time
go flushToFile(flushBuffer)
}
return
}
func handler(w http.ResponseWriter, r *http.Request) {
values := logBuffer.Values()
func handleQueryLog(w http.ResponseWriter, r *http.Request) {
// TODO: fetch values from disk if len(logBuffer) < queryLogSize
// TODO: cache output
values := logBuffer
var data = []map[string]interface{}{}
for _, value := range values {
entry, ok := value.(logEntry)
if !ok {
continue
for _, entry := range values {
var q *dns.Msg
var a *dns.Msg
if len(entry.Question) > 0 {
q = new(dns.Msg)
if err := q.Unpack(entry.Question); err != nil {
// ignore, log and move on
log.Printf("Failed to unpack dns message question: %s", err)
q = nil
}
}
if len(entry.Answer) > 0 {
a = new(dns.Msg)
if err := a.Unpack(entry.Answer); err != nil {
// ignore, log and move on
log.Printf("Failed to unpack dns message question: %s", err)
a = nil
}
}
jsonentry := map[string]interface{}{
@ -60,22 +110,25 @@ func handler(w http.ResponseWriter, r *http.Request) {
"time": entry.Time.Format(time.RFC3339),
"client": entry.IP,
}
question := map[string]interface{}{
"host": strings.ToLower(strings.TrimSuffix(entry.Question.Question[0].Name, ".")),
"type": dns.Type(entry.Question.Question[0].Qtype).String(),
"class": dns.Class(entry.Question.Question[0].Qclass).String(),
if q != nil {
jsonentry["question"] = map[string]interface{}{
"host": strings.ToLower(strings.TrimSuffix(q.Question[0].Name, ".")),
"type": dns.Type(q.Question[0].Qtype).String(),
"class": dns.Class(q.Question[0].Qclass).String(),
}
}
jsonentry["question"] = question
status, _ := response.Typify(entry.Answer, time.Now().UTC())
if a != nil {
status, _ := response.Typify(a, time.Now().UTC())
jsonentry["status"] = status.String()
}
if len(entry.Result.Rule) > 0 {
jsonentry["rule"] = entry.Result.Rule
}
if entry.Answer != nil && len(entry.Answer.Answer) > 0 {
if a != nil && len(a.Answer) > 0 {
var answers = []map[string]interface{}{}
for _, k := range entry.Answer.Answer {
for _, k := range a.Answer {
header := k.Header()
answer := map[string]interface{}{
"type": dns.TypeToString[header.Rrtype],
@ -137,17 +190,26 @@ func handler(w http.ResponseWriter, r *http.Request) {
}
func startQueryLogServer() {
listenAddr := "127.0.0.1:8618" // sha512sum of "querylog" then each byte summed
listenAddr := "127.0.0.1:8618" // 8618 is sha512sum of "querylog" then each byte summed
http.HandleFunc("/querylog", handler)
go periodicQueryLogRotate(queryLogRotationPeriod)
http.HandleFunc("/querylog", handleQueryLog)
if err := http.ListenAndServe(listenAddr, nil); err != nil {
log.Fatalf("error in ListenAndServe: %s", err)
}
}
func trace(text string) {
func trace(format string, args ...interface{}) {
pc := make([]uintptr, 10) // at least 1 entry needed
runtime.Callers(2, pc)
f := runtime.FuncForPC(pc[0])
log.Printf("%s(): %s\n", f.Name(), text)
var buf strings.Builder
buf.WriteString(fmt.Sprintf("%s(): ", path.Base(f.Name())))
text := fmt.Sprintf(format, args...)
buf.WriteString(text)
if len(text) == 0 || text[len(text)-1] != '\n' {
buf.WriteRune('\n')
}
fmt.Fprint(os.Stderr, buf.String())
}

View File

@ -0,0 +1,146 @@
package dnsfilter
import (
"bytes"
"compress/gzip"
"encoding/json"
"fmt"
"log"
"os"
"sync"
"time"
"github.com/go-test/deep"
)
const (
queryLogRotationPeriod = time.Hour * 24 // rotate the log every 24 hours
queryLogFileName = "querylog.json" // .gz added during compression
)
var (
fileWriteLock sync.Mutex
)
func flushToFile(buffer []logEntry) error {
if len(buffer) == 0 {
return nil
}
start := time.Now()
var b bytes.Buffer
e := json.NewEncoder(&b)
for _, entry := range buffer {
err := e.Encode(entry)
if err != nil {
log.Printf("Failed to marshal entry: %s", err)
return err
}
}
elapsed := time.Since(start)
log.Printf("%d elements serialized via json in %v: %d kB, %v/entry, %v/entry", len(buffer), elapsed, b.Len()/1024, float64(b.Len())/float64(len(buffer)), elapsed/time.Duration(len(buffer)))
err := checkBuffer(buffer, b)
if err != nil {
log.Printf("failed to check buffer: %s", err)
return err
}
filenamegz := queryLogFileName + ".gz"
var zb bytes.Buffer
zw := gzip.NewWriter(&zb)
zw.Name = queryLogFileName
zw.ModTime = time.Now()
_, err = zw.Write(b.Bytes())
if err != nil {
log.Printf("Couldn't compress to gzip: %s", err)
zw.Close()
return err
}
if err = zw.Close(); err != nil {
log.Printf("Couldn't close gzip writer: %s", err)
return err
}
fileWriteLock.Lock()
defer fileWriteLock.Unlock()
f, err := os.OpenFile(filenamegz, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
if err != nil {
log.Printf("failed to create file \"%s\": %s", filenamegz, err)
return err
}
defer f.Close()
n, err := f.Write(zb.Bytes())
if err != nil {
log.Printf("Couldn't write to file: %s", err)
return err
}
log.Printf("ok \"%s\": %v bytes written", filenamegz, n)
return nil
}
func checkBuffer(buffer []logEntry, b bytes.Buffer) error {
l := len(buffer)
d := json.NewDecoder(&b)
i := 0
for d.More() {
var entry logEntry
err := d.Decode(&entry)
if err != nil {
log.Printf("Failed to decode: %s", err)
return err
}
if diff := deep.Equal(entry, buffer[i]); diff != nil {
log.Printf("decoded buffer differs: %s", diff)
return fmt.Errorf("decoded buffer differs: %s", diff)
}
i++
}
if i != l {
err := fmt.Errorf("check fail: %d vs %d entries", l, i)
log.Print(err)
return err
}
log.Printf("check ok: %d entries", i)
return nil
}
func rotateQueryLog() error {
from := queryLogFileName + ".gz"
to := queryLogFileName + ".gz.1"
if _, err := os.Stat(from); os.IsNotExist(err) {
// do nothing, file doesn't exist
return nil
}
err := os.Rename(from, to)
if err != nil {
log.Printf("Failed to rename querylog: %s", err)
return err
}
log.Printf("Rotated from %s to %s successfully", from, to)
return nil
}
func periodicQueryLogRotate(t time.Duration) {
for range time.Tick(t) {
err := rotateQueryLog()
if err != nil {
log.Printf("Failed to rotate querylog: %s", err)
// do nothing, continue rotating
}
}
}

View File

@ -62,7 +62,12 @@ type stats struct {
var statistics stats
func initPeriodicStats(periodic *periodicStats) {
*periodic = periodicStats{}
periodic.Entries = statsEntries{}
periodic.LastRotate = time.Time{}
}
func init() {
purgeStats()
}
func purgeStats() {