Switch to golang/dep.

vendor/github.com/cenk/backoff/backoff.go

@@ -15,7 +15,7 @@ import "time"
 // BackOff is a backoff policy for retrying an operation.
 type BackOff interface {
 	// NextBackOff returns the duration to wait before retrying the operation,
-	// or backoff.Stop to indicate that no more retries should be made.
+	// or backoff. Stop to indicate that no more retries should be made.
 	//
 	// Example usage:
 	//

vendor/github.com/cenk/backoff/exponential.go

@@ -63,6 +63,7 @@ type ExponentialBackOff struct {
 
 	currentInterval time.Duration
 	startTime       time.Time
+	random          *rand.Rand
 }
 
 // Clock is an interface that returns current time for BackOff.
@@ -88,6 +89,7 @@ func NewExponentialBackOff() *ExponentialBackOff {
 		MaxInterval:         DefaultMaxInterval,
 		MaxElapsedTime:      DefaultMaxElapsedTime,
 		Clock:               SystemClock,
+		random:              rand.New(rand.NewSource(time.Now().UnixNano())),
 	}
 	b.Reset()
 	return b
@@ -116,13 +118,18 @@ func (b *ExponentialBackOff) NextBackOff() time.Duration {
 		return Stop
 	}
 	defer b.incrementCurrentInterval()
-	return getRandomValueFromInterval(b.RandomizationFactor, rand.Float64(), b.currentInterval)
+	if b.random == nil {
+		b.random = rand.New(rand.NewSource(time.Now().UnixNano()))
+	}
+	return getRandomValueFromInterval(b.RandomizationFactor, b.random.Float64(), b.currentInterval)
 }
 
 // GetElapsedTime returns the elapsed time since an ExponentialBackOff instance
 // is created and is reset when Reset() is called.
 //
-// The elapsed time is computed using time.Now().UnixNano().
+// The elapsed time is computed using time.Now().UnixNano(). It is
+// safe to call even while the backoff policy is used by a running
+// ticker.
 func (b *ExponentialBackOff) GetElapsedTime() time.Duration {
 	return b.Clock.Now().Sub(b.startTime)
 }

vendor/github.com/cenk/backoff/ticker.go

@@ -18,9 +18,12 @@ type Ticker struct {
 	stopOnce sync.Once
 }
 
-// NewTicker returns a new Ticker containing a channel that will send the time at times
-// specified by the BackOff argument. Ticker is guaranteed to tick at least once.
-// The channel is closed when Stop method is called or BackOff stops.
+// NewTicker returns a new Ticker containing a channel that will send
+// the time at times specified by the BackOff argument. Ticker is
+// guaranteed to tick at least once.  The channel is closed when Stop
+// method is called or BackOff stops. It is not safe to manipulate the
+// provided backoff policy (notably calling NextBackOff or Reset)
+// while the ticker is running.
 func NewTicker(b BackOff) *Ticker {
 	c := make(chan time.Time)
 	t := &Ticker{
@@ -29,6 +32,7 @@ func NewTicker(b BackOff) *Ticker {
 		b:    ensureContext(b),
 		stop: make(chan struct{}),
 	}
+	t.b.Reset()
 	go t.run()
 	runtime.SetFinalizer(t, (*Ticker).Stop)
 	return t
@@ -42,7 +46,6 @@ func (t *Ticker) Stop() {
 func (t *Ticker) run() {
 	c := t.c
 	defer close(c)
-	t.b.Reset()
 
 	// Ticker is guaranteed to tick at least once.
 	afterC := t.send(time.Now())

vendor/github.com/cenk/backoff/tries.go

@@ -0,0 +1,35 @@
+package backoff
+
+import "time"
+
+/*
+WithMaxRetries creates a wrapper around another BackOff, which will
+return Stop if NextBackOff() has been called too many times since
+the last time Reset() was called
+
+Note: Implementation is not thread-safe.
+*/
+func WithMaxRetries(b BackOff, max uint64) BackOff {
+	return &backOffTries{delegate: b, maxTries: max}
+}
+
+type backOffTries struct {
+	delegate BackOff
+	maxTries uint64
+	numTries uint64
+}
+
+func (b *backOffTries) NextBackOff() time.Duration {
+	if b.maxTries > 0 {
+		if b.maxTries <= b.numTries {
+			return Stop
+		}
+		b.numTries++
+	}
+	return b.delegate.NextBackOff()
+}
+
+func (b *backOffTries) Reset() {
+	b.numTries = 0
+	b.delegate.Reset()
+}