From 7e45c2fc2428679ac7454c5244b0130901449324 Mon Sep 17 00:00:00 2001
From: Simon Zolin <s.zolin@adguard.com>
Date: Fri, 8 Nov 2019 12:31:50 +0300
Subject: [PATCH] + new setting "dns.querylog_memsize"

* set 1000 entries by default (not 5000)
---
 home/config.go            | 14 +++++++++-----
 home/dns.go               |  1 +
 querylog/qlog.go          |  3 +--
 querylog/querylog.go      |  2 ++
 querylog/querylog_file.go |  2 +-
 querylog/querylog_test.go |  1 +
 6 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/home/config.go b/home/config.go
index 8622155f..cb264787 100644
--- a/home/config.go
+++ b/home/config.go
@@ -106,6 +106,7 @@ type dnsConfig struct {
 
 	QueryLogEnabled  bool   `yaml:"querylog_enabled"`  // if true, query log is enabled
 	QueryLogInterval uint32 `yaml:"querylog_interval"` // time interval for query log (in days)
+	QueryLogMemSize  uint32 `yaml:"querylog_memsize"`  // number of entries kept in memory before they are flushed to disk
 
 	dnsforward.FilteringConfig `yaml:",inline"`
 
@@ -161,11 +162,9 @@ var config = configuration{
 	BindPort:          3000,
 	BindHost:          "0.0.0.0",
 	DNS: dnsConfig{
-		BindHost:         "0.0.0.0",
-		Port:             53,
-		StatsInterval:    1,
-		QueryLogEnabled:  true,
-		QueryLogInterval: 1,
+		BindHost:      "0.0.0.0",
+		Port:          53,
+		StatsInterval: 1,
 		FilteringConfig: dnsforward.FilteringConfig{
 			ProtectionEnabled:  true,       // whether or not use any of dnsfilter features
 			BlockingMode:       "nxdomain", // mode how to answer filtered requests
@@ -202,6 +201,10 @@ func initConfig() {
 
 	config.WebSessionTTLHours = 30 * 24
 
+	config.DNS.QueryLogEnabled = true
+	config.DNS.QueryLogInterval = 90
+	config.DNS.QueryLogMemSize = 1000
+
 	config.DNS.CacheSize = 4 * 1024 * 1024
 	config.DNS.DnsfilterConf.SafeBrowsingCacheSize = 1 * 1024 * 1024
 	config.DNS.DnsfilterConf.SafeSearchCacheSize = 1 * 1024 * 1024
@@ -310,6 +313,7 @@ func (c *configuration) write() error {
 		config.queryLog.WriteDiskConfig(&dc)
 		config.DNS.QueryLogEnabled = dc.Enabled
 		config.DNS.QueryLogInterval = dc.Interval
+		config.DNS.QueryLogMemSize = dc.MemSize
 	}
 
 	if config.dnsFilter != nil {
diff --git a/home/dns.go b/home/dns.go
index af39ee12..0ec5a042 100644
--- a/home/dns.go
+++ b/home/dns.go
@@ -50,6 +50,7 @@ func initDNSServer() {
 		Enabled:        config.DNS.QueryLogEnabled,
 		BaseDir:        baseDir,
 		Interval:       config.DNS.QueryLogInterval,
+		MemSize:        config.DNS.QueryLogMemSize,
 		ConfigModified: onConfigModified,
 		HTTPRegister:   httpRegister,
 	}
diff --git a/querylog/qlog.go b/querylog/qlog.go
index 07b8cd5c..bf585c53 100644
--- a/querylog/qlog.go
+++ b/querylog/qlog.go
@@ -16,7 +16,6 @@ import (
 )
 
 const (
-	logBufferCap     = 5000            // maximum capacity of buffer before it's flushed to disk
 	queryLogFileName = "querylog.json" // .gz added during compression
 	getDataLimit     = 500             // GetData(): maximum log entries to return
 
@@ -147,7 +146,7 @@ func (l *queryLog) Add(question *dns.Msg, answer *dns.Msg, result *dnsfilter.Res
 	l.buffer = append(l.buffer, &entry)
 	needFlush := false
 	if !l.flushPending {
-		needFlush = len(l.buffer) >= logBufferCap
+		needFlush = len(l.buffer) >= int(l.conf.MemSize)
 		if needFlush {
 			l.flushPending = true
 		}
diff --git a/querylog/querylog.go b/querylog/querylog.go
index 5158a211..e7e790e7 100644
--- a/querylog/querylog.go
+++ b/querylog/querylog.go
@@ -13,6 +13,7 @@ import (
 type DiskConfig struct {
 	Enabled  bool
 	Interval uint32
+	MemSize  uint32
 }
 
 // QueryLog - main interface
@@ -32,6 +33,7 @@ type Config struct {
 	Enabled  bool
 	BaseDir  string // directory where log file is stored
 	Interval uint32 // interval to rotate logs (in days)
+	MemSize  uint32 // number of entries kept in memory before they are flushed to disk
 
 	// Called when the configuration is changed by HTTP request
 	ConfigModified func()
diff --git a/querylog/querylog_file.go b/querylog/querylog_file.go
index cc32afb0..a2250581 100644
--- a/querylog/querylog_file.go
+++ b/querylog/querylog_file.go
@@ -27,7 +27,7 @@ func (l *queryLog) flushLogBuffer(fullFlush bool) error {
 
 	// flush remainder to file
 	l.bufferLock.Lock()
-	needFlush := len(l.buffer) >= logBufferCap
+	needFlush := len(l.buffer) >= int(l.conf.MemSize)
 	if !needFlush && !fullFlush {
 		l.bufferLock.Unlock()
 		return nil
diff --git a/querylog/querylog_test.go b/querylog/querylog_test.go
index 63bcbfd8..5b2776cd 100644
--- a/querylog/querylog_test.go
+++ b/querylog/querylog_test.go
@@ -23,6 +23,7 @@ func TestQueryLog(t *testing.T) {
 	conf := Config{
 		Enabled:  true,
 		Interval: 1,
+		MemSize:  100,
 	}
 	conf.BaseDir = prepareTestDir()
 	defer func() { _ = os.RemoveAll(conf.BaseDir) }()