* stats: pass configuration object via stats.New()

home/dns.go

@@ -36,8 +36,11 @@ func initDNSServer(baseDir string) {
 		log.Fatalf("Cannot create DNS data dir at %s: %s", baseDir, err)
 	}
 
-	statsDBFilename := filepath.Join(baseDir, "stats.db")
+	statsConf := stats.Config{
-	config.stats, err = stats.New(statsDBFilename, config.DNS.StatsInterval, nil)
+		Filename:  filepath.Join(baseDir, "stats.db"),
+		LimitDays: config.DNS.StatsInterval,
+	}
+	config.stats, err = stats.New(statsConf)
 	if err != nil {
 		log.Fatal("Couldn't initialize statistics module")
 	}

stats/stats.go

@@ -8,12 +8,16 @@ import (
 
 type unitIDCallback func() uint32
 
+// Config - module configuration
+type Config struct {
+	Filename  string         // database file name
+	LimitDays uint32         // time limit (in days)
+	UnitID    unitIDCallback // user function to get the current unit ID.  If nil, the current time hour is used.
+}
+
 // New - create object
-// filename: DB file name
+func New(conf Config) (Stats, error) {
-// limit: time limit (in days)
+	return createObject(conf)
-// unitID: user function to get the current unit ID.  If nil, the current time hour is used.
-func New(filename string, limit uint32, unitID unitIDCallback) (Stats, error) {
-	return createObject(filename, limit, unitID)
 }
 
 // Stats - main interface

stats/stats_test.go

@@ -26,7 +26,11 @@ func UIntArrayEquals(a []uint64, b []uint64) bool {
 }
 
 func TestStats(t *testing.T) {
-	s, _ := New("./stats.db", 1, nil)
+	conf := Config{
+		Filename:  "./stats.db",
+		LimitDays: 1,
+	}
+	s, _ := New(conf)
 
 	e := Entry{}
 
@@ -73,7 +77,7 @@ func TestStats(t *testing.T) {
 
 	s.Clear()
 	s.Close()
-	os.Remove("./stats.db")
+	os.Remove(conf.Filename)
 }
 
 func TestLargeNumbers(t *testing.T) {
@@ -85,9 +89,13 @@ func TestLargeNumbers(t *testing.T) {
 	}
 
 	// log.SetLevel(log.DEBUG)
-	fn := "./stats.db"
+	conf := Config{
-	os.Remove(fn)
+		Filename:  "./stats.db",
-	s, _ := New(fn, 1, newID)
+		LimitDays: 1,
+		UnitID:    newID,
+	}
+	os.Remove(conf.Filename)
+	s, _ := New(conf)
 	e := Entry{}
 
 	n := 1000 // number of distinct clients and domains every hour
@@ -111,5 +119,5 @@ func TestLargeNumbers(t *testing.T) {
 	assert.True(t, d["num_dns_queries"].(uint64) == uint64(int(hour)*n))
 
 	s.Close()
-	os.Remove(fn)
+	os.Remove(conf.Filename)
 }

stats/stats_unit.go

@@ -22,10 +22,10 @@ const (
 // statsCtx - global context
 type statsCtx struct {
 	limit uint32 // maximum time we need to keep data for (in hours)
-	filename string         // database file name
-	unitID   unitIDCallback // user function which returns the current unit ID
 	db    *bolt.DB
 
+	conf Config
+
 	unit     *unit      // the current unit
 	unitLock sync.Mutex // protect 'unit'
 }
@@ -62,20 +62,19 @@ type unitDB struct {
 	TimeAvg uint32 // usec
 }
 
-func createObject(filename string, limitDays uint32, unitID unitIDCallback) (*statsCtx, error) {
+func createObject(conf Config) (*statsCtx, error) {
 	s := statsCtx{}
-	s.limit = limitDays * 24
+	s.limit = conf.LimitDays * 24
-	s.filename = filename
+	s.conf = conf
-	s.unitID = newUnitID
+	if conf.UnitID == nil {
-	if unitID != nil {
+		s.conf.UnitID = newUnitID
-		s.unitID = unitID
 	}
 
 	if !s.dbOpen() {
 		return nil, fmt.Errorf("open database")
 	}
 
-	id := s.unitID()
+	id := s.conf.UnitID()
 	tx := s.beginTxn(true)
 	var udb *unitDB
 	if tx != nil {
@@ -122,9 +121,9 @@ func createObject(filename string, limitDays uint32, unitID unitIDCallback) (*st
 func (s *statsCtx) dbOpen() bool {
 	var err error
 	log.Tracef("db.Open...")
-	s.db, err = bolt.Open(s.filename, 0644, nil)
+	s.db, err = bolt.Open(s.conf.Filename, 0644, nil)
 	if err != nil {
-		log.Error("Stats: open DB: %s: %s", s.filename, err)
+		log.Error("Stats: open DB: %s: %s", s.conf.Filename, err)
 		return false
 	}
 	log.Tracef("db.Open")
@@ -208,7 +207,7 @@ func (s *statsCtx) periodicFlush() {
 			break
 		}
 
-		id := s.unitID()
+		id := s.conf.UnitID()
 		if ptr.id == id {
 			time.Sleep(time.Second)
 			continue
@@ -406,10 +405,10 @@ func (s *statsCtx) Clear() {
 	}
 
 	u := unit{}
-	s.initUnit(&u, s.unitID())
+	s.initUnit(&u, s.conf.UnitID())
 	_ = s.swapUnit(&u)
 
-	err := os.Remove(s.filename)
+	err := os.Remove(s.conf.Filename)
 	if err != nil {
 		log.Error("os.Remove: %s", err)
 	}
@@ -481,7 +480,7 @@ func (s *statsCtx) GetData(timeUnit TimeUnit) map[string]interface{} {
 	}
 
 	units := []*unitDB{} //per-hour units
-	lastID := s.unitID()
+	lastID := s.conf.UnitID()
 	firstID := lastID - s.limit + 1
 	for i := firstID; i != lastID; i++ {
 		u := s.loadUnitFromDB(tx, i)