gomqtt is a very good libs and used in our projects, thank all gomqtt…

… contributors. But because some logics of our projects are different from gomqtt's, we cannot use some gomqtt's public structs directly. For example, we need a mqtt client with auto-reconnect feature and without any message cache in memory, so we must implement it by myself and in order to avoid to copy code we hope gomqtt/client/tracker can be marked as a public struct.

client/client.go

@@ -121,7 +121,7 @@ type Client struct {
 	clean bool
 
 	keepAlive     time.Duration
-	tracker       *tracker
+	tracker       *Tracker
 	futureStore   *future.Store
 	connectFuture *future.Future
 
@@ -177,7 +177,7 @@ func (c *Client) Connect(config *Config) (ConnectFuture, error) {
 
 	// allocate and initialize tracker
 	c.keepAlive = keepAlive
-	c.tracker = newTracker(keepAlive)
+	c.tracker = NewTracker(keepAlive)
 
 	// dial broker (with custom dialer if present)
 	if config.Dialer != nil {
@@ -482,7 +482,7 @@ func (c *Client) processor() error {
 		case *packet.Unsuback:
 			err = c.processUnsuback(typedPkt)
 		case *packet.Pingresp:
-			c.tracker.pong()
+			c.tracker.Pong()
 		case *packet.Publish:
 			err = c.processPublish(typedPkt)
 		case *packet.Puback:
@@ -749,12 +749,12 @@ func (c *Client) processPubrel(id packet.ID) error {
 func (c *Client) pinger() error {
 	for {
 		// get current window
-		window := c.tracker.window()
+		window := c.tracker.Window()
 
 		// check if ping is due
 		if window < 0 {
 			// check if a pong has already been sent
-			if c.tracker.pending() {
+			if c.tracker.Pending() {
 				return c.die(ErrClientMissingPong, true, false)
 			}
 
@@ -765,7 +765,7 @@ func (c *Client) pinger() error {
 			}
 
 			// save ping attempt
-			c.tracker.ping()
+			c.tracker.Ping()
 		} else {
 			// log keep alive delay
 			if c.Logger != nil {
@@ -787,7 +787,7 @@ func (c *Client) pinger() error {
 // sends packet and updates lastSend
 func (c *Client) send(pkt packet.Generic, async bool) error {
 	// reset keep alive tracker
-	c.tracker.reset()
+	c.tracker.Reset()
 
 	// send packet
 	err := c.conn.Send(pkt, async)

client/tracker.go

@@ -5,57 +5,57 @@ import (
 	"time"
 )
 
-// a tracker keeps track of keep alive intervals
-type tracker struct {
+// Tracker a tracker keeps track of keep alive intervals
+type Tracker struct {
 	sync.RWMutex
 
 	last    time.Time
 	pings   uint8
 	timeout time.Duration
 }
 
-// returns a new tracker
-func newTracker(timeout time.Duration) *tracker {
-	return &tracker{
+// NewTracker returns a new tracker
+func NewTracker(timeout time.Duration) *Tracker {
+	return &Tracker{
 		last:    time.Now(),
 		timeout: timeout,
 	}
 }
 
-// updates the tracker
-func (t *tracker) reset() {
+// Reset updates the tracker
+func (t *Tracker) Reset() {
 	t.Lock()
 	defer t.Unlock()
 
 	t.last = time.Now()
 }
 
-// returns the current time window
-func (t *tracker) window() time.Duration {
+// Window returns the current time window
+func (t *Tracker) Window() time.Duration {
 	t.RLock()
 	defer t.RUnlock()
 
 	return t.timeout - time.Since(t.last)
 }
 
-// mark ping
-func (t *tracker) ping() {
+// Ping mark ping
+func (t *Tracker) Ping() {
 	t.Lock()
 	defer t.Unlock()
 
 	t.pings++
 }
 
-// mark pong
-func (t *tracker) pong() {
+// Pong mark pong
+func (t *Tracker) Pong() {
 	t.Lock()
 	defer t.Unlock()
 
 	t.pings--
 }
 
-// returns if pings are pending
-func (t *tracker) pending() bool {
+// Pending returns if pings are pending
+func (t *Tracker) Pending() bool {
 	t.RLock()
 	defer t.RUnlock()
 

client/tracker_test.go

@@ -8,19 +8,19 @@ import (
 )
 
 func TestTracker(t *testing.T) {
-	tracker := newTracker(10 * time.Millisecond)
-	assert.False(t, tracker.pending())
-	assert.True(t, tracker.window() > 0)
+	tracker := NewTracker(10 * time.Millisecond)
+	assert.False(t, tracker.Pending())
+	assert.True(t, tracker.Window() > 0)
 
 	time.Sleep(10 * time.Millisecond)
-	assert.True(t, tracker.window() <= 0)
+	assert.True(t, tracker.Window() <= 0)
 
-	tracker.reset()
-	assert.True(t, tracker.window() > 0)
+	tracker.Reset()
+	assert.True(t, tracker.Window() > 0)
 
-	tracker.ping()
-	assert.True(t, tracker.pending())
+	tracker.Ping()
+	assert.True(t, tracker.Pending())
 
-	tracker.pong()
-	assert.False(t, tracker.pending())
+	tracker.Pong()
+	assert.False(t, tracker.Pending())
 }