dnsforward -- Move querylog from coredns plugin, a more complex migration with proper API took too long so a simple move was used instead to save time.
This commit is contained in:
Eugene Bujak
253
dnsforward/querylog_file.go
Normal file
253
dnsforward/querylog_file.go
Normal file
@@ -0,0 +1,253 @@
|
||||
package dnsforward
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"compress/gzip"
|
||||
"encoding/json"
|
||||
"fmt"
|
||||
"log"
|
||||
"os"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/go-test/deep"
|
||||
)
|
||||
|
||||
var (
|
||||
fileWriteLock sync.Mutex
|
||||
)
|
||||
|
||||
const enableGzip = false
|
||||
|
||||
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
|
||||
}
|
||||
|
||||
var zb bytes.Buffer
|
||||
filename := queryLogFileName
|
||||
|
||||
// gzip enabled?
|
||||
if enableGzip {
|
||||
filename += ".gz"
|
||||
|
||||
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
|
||||
}
|
||||
} else {
|
||||
zb = b
|
||||
}
|
||||
|
||||
fileWriteLock.Lock()
|
||||
defer fileWriteLock.Unlock()
|
||||
f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
|
||||
if err != nil {
|
||||
log.Printf("failed to create file \"%s\": %s", filename, 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", filename, n)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func checkBuffer(buffer []*logEntry, b bytes.Buffer) error {
|
||||
l := len(buffer)
|
||||
d := json.NewDecoder(&b)
|
||||
|
||||
i := 0
|
||||
for d.More() {
|
||||
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
|
||||
to := queryLogFileName + ".1"
|
||||
|
||||
if enableGzip {
|
||||
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() {
|
||||
for range time.Tick(queryLogRotationPeriod) {
|
||||
err := rotateQueryLog()
|
||||
if err != nil {
|
||||
log.Printf("Failed to rotate querylog: %s", err)
|
||||
// do nothing, continue rotating
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func genericLoader(onEntry func(entry *logEntry) error, needMore func() bool, timeWindow time.Duration) error {
|
||||
now := time.Now()
|
||||
// read from querylog files, try newest file first
|
||||
files := []string{}
|
||||
|
||||
if enableGzip {
|
||||
files = []string{
|
||||
queryLogFileName + ".gz",
|
||||
queryLogFileName + ".gz.1",
|
||||
}
|
||||
} else {
|
||||
files = []string{
|
||||
queryLogFileName,
|
||||
queryLogFileName + ".1",
|
||||
}
|
||||
}
|
||||
|
||||
// read from all files
|
||||
for _, file := range files {
|
||||
if !needMore() {
|
||||
break
|
||||
}
|
||||
if _, err := os.Stat(file); os.IsNotExist(err) {
|
||||
// do nothing, file doesn't exist
|
||||
continue
|
||||
}
|
||||
|
||||
f, err := os.Open(file)
|
||||
if err != nil {
|
||||
log.Printf("Failed to open file \"%s\": %s", file, err)
|
||||
// try next file
|
||||
continue
|
||||
}
|
||||
defer f.Close()
|
||||
|
||||
var d *json.Decoder
|
||||
|
||||
if enableGzip {
|
||||
trace("Creating gzip reader")
|
||||
zr, err := gzip.NewReader(f)
|
||||
if err != nil {
|
||||
log.Printf("Failed to create gzip reader: %s", err)
|
||||
continue
|
||||
}
|
||||
defer zr.Close()
|
||||
|
||||
trace("Creating json decoder")
|
||||
d = json.NewDecoder(zr)
|
||||
} else {
|
||||
d = json.NewDecoder(f)
|
||||
}
|
||||
|
||||
i := 0
|
||||
over := 0
|
||||
max := 10000 * time.Second
|
||||
var sum time.Duration
|
||||
// entries on file are in oldest->newest order
|
||||
// we want maxLen newest
|
||||
for d.More() {
|
||||
if !needMore() {
|
||||
break
|
||||
}
|
||||
var entry logEntry
|
||||
err := d.Decode(&entry)
|
||||
if err != nil {
|
||||
log.Printf("Failed to decode: %s", err)
|
||||
// next entry can be fine, try more
|
||||
continue
|
||||
}
|
||||
|
||||
if now.Sub(entry.Time) > timeWindow {
|
||||
// trace("skipping entry") // debug logging
|
||||
continue
|
||||
}
|
||||
|
||||
if entry.Elapsed > max {
|
||||
over++
|
||||
} else {
|
||||
sum += entry.Elapsed
|
||||
}
|
||||
|
||||
i++
|
||||
err = onEntry(&entry)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
elapsed := time.Since(now)
|
||||
var perunit time.Duration
|
||||
var avg time.Duration
|
||||
if i > 0 {
|
||||
perunit = elapsed / time.Duration(i)
|
||||
avg = sum / time.Duration(i)
|
||||
}
|
||||
log.Printf("file \"%s\": read %d entries in %v, %v/entry, %v over %v, %v avg", file, i, elapsed, perunit, over, max, avg)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
Reference in New Issue
Block a user