deprecate this repo

README.md

@@ -1,3 +1,8 @@
+# DEPRECATION NOTICE
+
+This package has moved into go-libp2p, split into multiple sub-packages:
+`github.com/libp2p/go-libp2p/p2p/discovery`.
+
 # go-libp2p-discovery
 
 [![](https://img.shields.io/badge/made%20by-Protocol%20Labs-blue.svg?style=flat-square)](https://protocol.ai)

backoff.go

@@ -1,228 +1,67 @@
 package discovery
 
 import (
-	"math"
 	"math/rand"
-	"sync"
 	"time"
+
+	dbackoff "github.com/libp2p/go-libp2p/p2p/discovery/backoff"
 )
 
-type BackoffFactory func() BackoffStrategy
+// Deprecated: use go-libp2p/p2p/discovery/backoff.BackoffFactory instead.
+type BackoffFactory = dbackoff.BackoffFactory
 
 // BackoffStrategy describes how backoff will be implemented. BackoffStratgies are stateful.
-type BackoffStrategy interface {
-	// Delay calculates how long the next backoff duration should be, given the prior calls to Delay
-	Delay() time.Duration
-	// Reset clears the internal state of the BackoffStrategy
-	Reset()
-}
+// Deprecated: use go-libp2p/p2p/discovery/backoff.BackoffStrategy instead.
+type BackoffStrategy = dbackoff.BackoffStrategy
 
 // Jitter implementations taken roughly from https://aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter/
 
 // Jitter must return a duration between min and max. Min must be lower than, or equal to, max.
-type Jitter func(duration, min, max time.Duration, rng *rand.Rand) time.Duration
+// Deprecated: use go-libp2p/p2p/discovery/backoff.Jitter instead.
+type Jitter = dbackoff.Jitter
 
 // FullJitter returns a random number uniformly chose from the range [min, boundedDur].
 // boundedDur is the duration bounded between min and max.
+// Deprecated: use go-libp2p/p2p/discovery/backoff.FullJitter instead.
 func FullJitter(duration, min, max time.Duration, rng *rand.Rand) time.Duration {
-	if duration <= min {
-		return min
-	}
-
-	normalizedDur := boundedDuration(duration, min, max) - min
-
-	return boundedDuration(time.Duration(rng.Int63n(int64(normalizedDur)))+min, min, max)
+	return dbackoff.FullJitter(duration, min, max, rng)
 }
 
 // NoJitter returns the duration bounded between min and max
+// Deprecated: use go-libp2p/p2p/discovery/backoff.NoJitter instead.
 func NoJitter(duration, min, max time.Duration, rng *rand.Rand) time.Duration {
-	return boundedDuration(duration, min, max)
-}
-
-type randomizedBackoff struct {
-	min time.Duration
-	max time.Duration
-	rng *rand.Rand
-}
-
-func (b *randomizedBackoff) BoundedDelay(duration time.Duration) time.Duration {
-	return boundedDuration(duration, b.min, b.max)
-}
-
-func boundedDuration(d, min, max time.Duration) time.Duration {
-	if d < min {
-		return min
-	}
-	if d > max {
-		return max
-	}
-	return d
-}
-
-type attemptBackoff struct {
-	attempt int
-	jitter  Jitter
-	randomizedBackoff
-}
-
-func (b *attemptBackoff) Reset() {
-	b.attempt = 0
+	return dbackoff.NoJitter(duration, min, max, rng)
 }
 
 // NewFixedBackoff creates a BackoffFactory with a constant backoff duration
+// Deprecated: use go-libp2p/p2p/discovery/backoff.NewFixedBackoff instead.
 func NewFixedBackoff(delay time.Duration) BackoffFactory {
-	return func() BackoffStrategy {
-		return &fixedBackoff{delay: delay}
-	}
-}
-
-type fixedBackoff struct {
-	delay time.Duration
-}
-
-func (b *fixedBackoff) Delay() time.Duration {
-	return b.delay
+	return dbackoff.NewFixedBackoff(delay)
 }
 
-func (b *fixedBackoff) Reset() {}
-
 // NewPolynomialBackoff creates a BackoffFactory with backoff of the form c0*x^0, c1*x^1, ...cn*x^n where x is the attempt number
 // jitter is the function for adding randomness around the backoff
 // timeUnits are the units of time the polynomial is evaluated in
 // polyCoefs is the array of polynomial coefficients from [c0, c1, ... cn]
+// Deprecated: use go-libp2p/p2p/discovery/backoff.NewPolynomialBackoff instead.
 func NewPolynomialBackoff(min, max time.Duration, jitter Jitter,
 	timeUnits time.Duration, polyCoefs []float64, rngSrc rand.Source) BackoffFactory {
-	rng := rand.New(&lockedSource{src: rngSrc})
-	return func() BackoffStrategy {
-		return &polynomialBackoff{
-			attemptBackoff: attemptBackoff{
-				randomizedBackoff: randomizedBackoff{
-					min: min,
-					max: max,
-					rng: rng,
-				},
-				jitter: jitter,
-			},
-			timeUnits: timeUnits,
-			poly:      polyCoefs,
-		}
-	}
-}
-
-type polynomialBackoff struct {
-	attemptBackoff
-	timeUnits time.Duration
-	poly      []float64
-}
-
-func (b *polynomialBackoff) Delay() time.Duration {
-	var polySum float64
-	switch len(b.poly) {
-	case 0:
-		return 0
-	case 1:
-		polySum = b.poly[0]
-	default:
-		polySum = b.poly[0]
-		exp := 1
-		attempt := b.attempt
-		b.attempt++
-
-		for _, c := range b.poly[1:] {
-			exp *= attempt
-			polySum += float64(exp) * c
-		}
-	}
-	return b.jitter(time.Duration(float64(b.timeUnits)*polySum), b.min, b.max, b.rng)
+	return dbackoff.NewPolynomialBackoff(min, max, jitter, timeUnits, polyCoefs, rngSrc)
 }
 
 // NewExponentialBackoff creates a BackoffFactory with backoff of the form base^x + offset where x is the attempt number
 // jitter is the function for adding randomness around the backoff
 // timeUnits are the units of time the base^x is evaluated in
+// Deprecated: use go-libp2p/p2p/discovery/backoff.NewExponentialBackoff instead.
 func NewExponentialBackoff(min, max time.Duration, jitter Jitter,
 	timeUnits time.Duration, base float64, offset time.Duration, rngSrc rand.Source) BackoffFactory {
-	rng := rand.New(&lockedSource{src: rngSrc})
-	return func() BackoffStrategy {
-		return &exponentialBackoff{
-			attemptBackoff: attemptBackoff{
-				randomizedBackoff: randomizedBackoff{
-					min: min,
-					max: max,
-					rng: rng,
-				},
-				jitter: jitter,
-			},
-			timeUnits: timeUnits,
-			base:      base,
-			offset:    offset,
-		}
-	}
-}
-
-type exponentialBackoff struct {
-	attemptBackoff
-	timeUnits time.Duration
-	base      float64
-	offset    time.Duration
-}
-
-func (b *exponentialBackoff) Delay() time.Duration {
-	attempt := b.attempt
-	b.attempt++
-	return b.jitter(
-		time.Duration(math.Pow(b.base, float64(attempt))*float64(b.timeUnits))+b.offset, b.min, b.max, b.rng)
+	return dbackoff.NewExponentialBackoff(min, max, jitter, timeUnits, base, offset, rngSrc)
 }
 
 // NewExponentialDecorrelatedJitter creates a BackoffFactory with backoff of the roughly of the form base^x where x is the attempt number.
 // Delays start at the minimum duration and after each attempt delay = rand(min, delay * base), bounded by the max
 // See https://aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter/ for more information
+// Deprecated: use go-libp2p/p2p/discovery/backoff.NewExponentialDecorrelatedJitter instead.
 func NewExponentialDecorrelatedJitter(min, max time.Duration, base float64, rngSrc rand.Source) BackoffFactory {
-	rng := rand.New(&lockedSource{src: rngSrc})
-	return func() BackoffStrategy {
-		return &exponentialDecorrelatedJitter{
-			randomizedBackoff: randomizedBackoff{
-				min: min,
-				max: max,
-				rng: rng,
-			},
-			base: base,
-		}
-	}
-}
-
-type exponentialDecorrelatedJitter struct {
-	randomizedBackoff
-	base      float64
-	lastDelay time.Duration
-}
-
-func (b *exponentialDecorrelatedJitter) Delay() time.Duration {
-	if b.lastDelay < b.min {
-		b.lastDelay = b.min
-		return b.lastDelay
-	}
-
-	nextMax := int64(float64(b.lastDelay) * b.base)
-	b.lastDelay = boundedDuration(time.Duration(b.rng.Int63n(nextMax-int64(b.min)))+b.min, b.min, b.max)
-	return b.lastDelay
-}
-
-func (b *exponentialDecorrelatedJitter) Reset() { b.lastDelay = 0 }
-
-type lockedSource struct {
-	lk  sync.Mutex
-	src rand.Source
-}
-
-func (r *lockedSource) Int63() (n int64) {
-	r.lk.Lock()
-	n = r.src.Int63()
-	r.lk.Unlock()
-	return
-}
-
-func (r *lockedSource) Seed(seed int64) {
-	r.lk.Lock()
-	r.src.Seed(seed)
-	r.lk.Unlock()
+	return dbackoff.NewExponentialDecorrelatedJitter(min, max, base, rngSrc)
 }