1 files changed, 97 insertions, 0 deletions
diff --git a/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go b/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go
new file mode 100644
index 000000000..358b69e7f
--- /dev/null
+++ b/vendor/github.com/hpcloud/tail/ratelimiter/leakybucket.go
@@ -0,0 +1,97 @@
+// Package ratelimiter implements the Leaky Bucket ratelimiting algorithm with memcached and in-memory backends.
+package ratelimiter
+
+import (
+	"time"
+)
+
+type LeakyBucket struct {
+	Size         uint16
+	Fill         float64
+	LeakInterval time.Duration // time.Duration for 1 unit of size to leak
+	Lastupdate   time.Time
+	Now          func() time.Time
+}
+
+func NewLeakyBucket(size uint16, leakInterval time.Duration) *LeakyBucket {
+	bucket := LeakyBucket{
+		Size:         size,
+		Fill:         0,
+		LeakInterval: leakInterval,
+		Now:          time.Now,
+		Lastupdate:   time.Now(),
+	}
+
+	return &bucket
+}
+
+func (b *LeakyBucket) updateFill() {
+	now := b.Now()
+	if b.Fill > 0 {
+		elapsed := now.Sub(b.Lastupdate)
+
+		b.Fill -= float64(elapsed) / float64(b.LeakInterval)
+		if b.Fill < 0 {
+			b.Fill = 0
+		}
+	}
+	b.Lastupdate = now
+}
+
+func (b *LeakyBucket) Pour(amount uint16) bool {
+	b.updateFill()
+
+	var newfill float64 = b.Fill + float64(amount)
+
+	if newfill > float64(b.Size) {
+		return false
+	}
+
+	b.Fill = newfill
+
+	return true
+}
+
+// The time at which this bucket will be completely drained
+func (b *LeakyBucket) DrainedAt() time.Time {
+	return b.Lastupdate.Add(time.Duration(b.Fill * float64(b.LeakInterval)))
+}
+
+// The duration until this bucket is completely drained
+func (b *LeakyBucket) TimeToDrain() time.Duration {
+	return b.DrainedAt().Sub(b.Now())
+}
+
+func (b *LeakyBucket) TimeSinceLastUpdate() time.Duration {
+	return b.Now().Sub(b.Lastupdate)
+}
+
+type LeakyBucketSer struct {
+	Size         uint16
+	Fill         float64
+	LeakInterval time.Duration // time.Duration for 1 unit of size to leak
+	Lastupdate   time.Time
+}
+
+func (b *LeakyBucket) Serialise() *LeakyBucketSer {
+	bucket := LeakyBucketSer{
+		Size:         b.Size,
+		Fill:         b.Fill,
+		LeakInterval: b.LeakInterval,
+		Lastupdate:   b.Lastupdate,
+	}
+
+	return &bucket
+}
+
+func (b *LeakyBucketSer) DeSerialise() *LeakyBucket {
+	bucket := LeakyBucket{
+		Size:         b.Size,
+		Fill:         b.Fill,
+		LeakInterval: b.LeakInterval,
+		Lastupdate:   b.Lastupdate,
+		Now:          time.Now,
+	}
+
+	return &bucket
+}