Pull request 2145: 5992-stats-qlog-custom-dir

Updates #5992.

Squashed commit of the following:

commit 39d3df705ef68672ec9406d81e00daf52a3b3c70
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 12 15:25:22 2024 +0300

    all: fix typo

commit 21e03e4d5a7624a68add53734a127652053845a2
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 12 15:22:35 2024 +0300

    all: upd docs

commit 11180061619f4352774d4bc8c85b481ae28f0d0b
Merge: ac5fd8dc8 7f8370744
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 12 14:57:35 2024 +0300

    Merge branch 'master' into 5992-stats-qlog-custom-dir

commit ac5fd8dc82c9c6e88a182cd6e6aed07bf3548639
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 7 14:55:51 2024 +0300

    all: upd chlog

commit fe00652e158db65e0e735a19cf88aa999ece3e62
Merge: 21ad1ecf7 56b98080f
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 7 14:53:24 2024 +0300

    Merge branch 'master' into 5992-stats-qlog-custom-dir

commit 21ad1ecf7b30c3c8f45d54210d7297966126b0f7
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Wed Feb 7 14:52:12 2024 +0300

    home: imp docs

commit 739b158de77e673ef80efdaa523044939ea879d5
Author: Stanislav Chzhen <s.chzhen@adguard.com>
Date:   Mon Feb 5 20:15:50 2024 +0300

    home: add stats qlog custom dir

CHANGELOG.md

@@ -30,6 +30,8 @@ NOTE: Add new changes BELOW THIS COMMENT.
 
 ### Added
 
+- Ability to define custom directories for storage of query log files and
+  statistics ([#5992]).
 - Context menu item in the Query Log to add a Client to the Persistent client
   list ([#6679]).
 
@@ -59,6 +61,7 @@ NOTE: Add new changes BELOW THIS COMMENT.
 
 - Go 1.20 support, as it has reached end of life.
 
+[#5992]: https://github.com/AdguardTeam/AdGuardHome/issues/5992
 [#6679]: https://github.com/AdguardTeam/AdGuardHome/issues/6679
 
 [go-toolchain]: https://go.dev/blog/toolchain

internal/aghnet/hostscontainer.go

@@ -154,8 +154,8 @@ func pathsToPatterns(fsys fs.FS, paths []string) (patterns []string, err error)
 }
 
 // handleEvents concurrently handles the file system events.  It closes the
-// update channel of HostsContainer when finishes.  It's used to be called
+// update channel of HostsContainer when finishes.  It is intended to be used as
-// within a separate goroutine.
+// a goroutine.
 func (hc *HostsContainer) handleEvents() {
 	defer log.OnPanic(fmt.Sprintf("%s: handling events", hostsContainerPrefix))
 

internal/aghos/fswatcher.go

@@ -66,7 +66,7 @@ func NewOSWritesWatcher() (w FSWatcher, err error) {
 	return fsw, nil
 }
 
-// handleErrors handles accompanying errors.  It used to be called in a separate
+// handleErrors handles accompanying errors.  It is intended to be used as a
 // goroutine.
 func (w *osWatcher) handleErrors() {
 	defer log.OnPanic(fmt.Sprintf("%s: handling errors", osWatcherPref))
@@ -100,7 +100,7 @@ func (w *osWatcher) Close() (err error) {
 }
 
 // handleEvents notifies about the received file system's event if needed.  It
-// used to be called in a separate goroutine.
+// is intended to be used as a goroutine.
 func (w *osWatcher) handleEvents() {
 	defer log.OnPanic(fmt.Sprintf("%s: handling events", osWatcherPref))
 

internal/home/clients.go

@@ -140,8 +140,7 @@ func (clients *clientsContainer) Init(
 }
 
 // handleHostsUpdates receives the updates from the hosts container and adds
-// them to the clients container.  It's used to be called in a separate
+// them to the clients container.  It is intended to be used as a goroutine.
-// goroutine.
 func (clients *clientsContainer) handleHostsUpdates() {
 	for upd := range clients.etcHosts.Upd() {
 		clients.addFromHostsFile(upd)

internal/home/config.go

@@ -259,6 +259,10 @@ type tlsConfigSettings struct {
 }
 
 type queryLogConfig struct {
+	// DirPath is the custom directory for logs.  If it's empty the default
+	// directory will be used.  See [homeContext.getDataDir].
+	DirPath string `yaml:"dir_path"`
+
 	// Ignored is the list of host names, which should not be written to log.
 	// "." is considered to be the root domain.
 	Ignored []string `yaml:"ignored"`
@@ -278,6 +282,10 @@ type queryLogConfig struct {
 }
 
 type statsConfig struct {
+	// DirPath is the custom directory for statistics.  If it's empty the
+	// default directory is used.  See [homeContext.getDataDir].
+	DirPath string `yaml:"dir_path"`
+
 	// Ignored is the list of host names, which should not be counted.
 	Ignored []string `yaml:"ignored"`
 

internal/home/dns.go

@@ -46,12 +46,15 @@ func onConfigModified() {
 // server and initializes it at last.  It also must not be called unless
 // [config] and [Context] are initialized.
 func initDNS() (err error) {
-	baseDir := Context.getDataDir()
-
 	anonymizer := config.anonymizer()
 
+	statsDir, querylogDir, err := checkStatsAndQuerylogDirs(&Context, config)
+	if err != nil {
+		return err
+	}
+
 	statsConf := stats.Config{
-		Filename:          filepath.Join(baseDir, "stats.db"),
+		Filename:          filepath.Join(statsDir, "stats.db"),
 		Limit:             config.Stats.Interval.Duration,
 		ConfigModified:    onConfigModified,
 		HTTPRegister:      httpRegister,
@@ -75,7 +78,7 @@ func initDNS() (err error) {
 		ConfigModified:    onConfigModified,
 		HTTPRegister:      httpRegister,
 		FindClient:        Context.clients.findMultiple,
-		BaseDir:           baseDir,
+		BaseDir:           querylogDir,
 		AnonymizeClientIP: config.DNS.AnonymizeClientIP,
 		RotationIvl:       config.QueryLog.Interval.Duration,
 		MemSize:           config.QueryLog.MemSize,
@@ -545,3 +548,50 @@ func (r safeSearchResolver) LookupIP(
 
 	return ips, nil
 }
+
+// checkStatsAndQuerylogDirs checks and returns directory paths to store
+// statistics and query log.
+func checkStatsAndQuerylogDirs(
+	ctx *homeContext,
+	conf *configuration,
+) (statsDir, querylogDir string, err error) {
+	baseDir := ctx.getDataDir()
+
+	statsDir = conf.Stats.DirPath
+	if statsDir == "" {
+		statsDir = baseDir
+	} else {
+		err = checkDir(statsDir)
+		if err != nil {
+			return "", "", fmt.Errorf("statistics: custom directory: %w", err)
+		}
+	}
+
+	querylogDir = conf.QueryLog.DirPath
+	if querylogDir == "" {
+		querylogDir = baseDir
+	} else {
+		err = checkDir(querylogDir)
+		if err != nil {
+			return "", "", fmt.Errorf("querylog: custom directory: %w", err)
+		}
+	}
+
+	return statsDir, querylogDir, nil
+}
+
+// checkDir checks if the path is a directory.  It's used to check for
+// misconfiguration at startup.
+func checkDir(path string) (err error) {
+	var fi os.FileInfo
+	if fi, err = os.Stat(path); err != nil {
+		// Don't wrap the error, since it's informative enough as is.
+		return err
+	}
+
+	if !fi.IsDir() {
+		return fmt.Errorf("%q is not a directory", path)
+	}
+
+	return nil
+}

internal/querylog/search.go

@@ -49,8 +49,8 @@ func (l *queryLog) client(clientID, ip string, cache clientCache) (c *Client, er
 // the total amount of records in the buffer at the moment of searching.
 // l.confMu is expected to be locked.
 func (l *queryLog) searchMemory(params *searchParams, cache clientCache) (entries []*logEntry, total int) {
-	// We use this configuration check because a buffer can contain a single log
+	// Check memory size, as the buffer can contain a single log record.  See
-	// record.  See [newQueryLog].
+	// [newQueryLog].
 	if l.conf.MemSize == 0 {
 		return nil, 0
 	}