use a mock clock in bandwidth tests (#276)

go.mod

@@ -3,12 +3,13 @@ module github.com/libp2p/go-libp2p-core
 go 1.17
 
 require (
+	github.com/benbjohnson/clock v1.3.0
 	github.com/btcsuite/btcd/btcec/v2 v2.1.3
 	github.com/gogo/protobuf v1.3.1
 	github.com/ipfs/go-cid v0.2.0
 	github.com/ipfs/go-log/v2 v2.5.1
 	github.com/libp2p/go-buffer-pool v0.0.2
-	github.com/libp2p/go-flow-metrics v0.0.3
+	github.com/libp2p/go-flow-metrics v0.1.0
 	github.com/libp2p/go-msgio v0.0.6
 	github.com/libp2p/go-openssl v0.0.7
 	github.com/minio/sha256-simd v1.0.0
@@ -37,5 +38,5 @@ require (
 	go.uber.org/zap v1.19.1 // indirect
 	golang.org/x/crypto v0.0.0-20210506145944-38f3c27a63bf // indirect
 	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c // indirect
-	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,5 +1,6 @@
-github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
 github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
+github.com/benbjohnson/clock v1.3.0 h1:ip6w0uFQkncKQ979AypyG0ER7mqUSBdKLOgAle/AT8A=
+github.com/benbjohnson/clock v1.3.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/btcsuite/btcd/btcec/v2 v2.1.3 h1:xM/n3yIhHAhHy04z4i43C8p4ehixJZMsnrVJkgl+MTE=
 github.com/btcsuite/btcd/btcec/v2 v2.1.3/go.mod h1:ctjw4H1kknNJmRN4iP1R7bTQ+v3GJkZBd6mui8ZsAZE=
 github.com/btcsuite/btcd/chaincfg/chainhash v1.0.0/go.mod h1:7SFka0XMvUgj3hfZtydOrQY2mwhPclbT2snogU7SQQc=
@@ -30,8 +31,8 @@ github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/libp2p/go-buffer-pool v0.0.2 h1:QNK2iAFa8gjAe1SPz6mHSMuCcjs+X1wlHzeOSqcmlfs=
 github.com/libp2p/go-buffer-pool v0.0.2/go.mod h1:MvaB6xw5vOrDl8rYZGLFdKAuk/hRoRZd1Vi32+RXyFM=
-github.com/libp2p/go-flow-metrics v0.0.3 h1:8tAs/hSdNvUiLgtlSy3mxwxWP4I9y/jlkPFT7epKdeM=
+github.com/libp2p/go-flow-metrics v0.1.0 h1:0iPhMI8PskQwzh57jB9WxIuIOQ0r+15PChFGkx3Q3WM=
-github.com/libp2p/go-flow-metrics v0.0.3/go.mod h1:HeoSNUrOJVK1jEpDqVEiUOIXqhbnS27omG0uWU5slZs=
+github.com/libp2p/go-flow-metrics v0.1.0/go.mod h1:4Xi8MX8wj5aWNDAZttg6UPmc0ZrnFNsMtpsYUClFtro=
 github.com/libp2p/go-msgio v0.0.6 h1:lQ7Uc0kS1wb1EfRxO2Eir/RJoHkHn7t6o+EiwsYIKJA=
 github.com/libp2p/go-msgio v0.0.6/go.mod h1:4ecVB6d9f4BDSL5fqvPiC4A3KivjWn+Venn/1ALLMWA=
 github.com/libp2p/go-openssl v0.0.7 h1:eCAzdLejcNVBzP/iZM9vqHnQm+XyCEbSSIheIPRGNsw=
@@ -127,5 +128,6 @@ gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

metrics/bandwidth_test.go

@@ -2,16 +2,25 @@ package metrics
 
 import (
 	"fmt"
-	"math"
-	"runtime"
 	"sync"
 	"testing"
 	"time"
 
 	"github.com/libp2p/go-libp2p-core/peer"
 	"github.com/libp2p/go-libp2p-core/protocol"
+
+	"github.com/libp2p/go-flow-metrics"
+
+	"github.com/benbjohnson/clock"
+	"github.com/stretchr/testify/require"
 )
 
+var cl = clock.NewMock()
+
+func init() {
+	flow.SetClock(cl)
+}
+
 func BenchmarkBandwidthCounter(b *testing.B) {
 	b.StopTimer()
 	b.ResetTimer()
@@ -49,20 +58,13 @@ func round(bwc *BandwidthCounter, b *testing.B) {
 	b.StopTimer()
 }
 
-// Allow 1% errors for bw calculations.
-const acceptableError = 0.01
-
 func TestBandwidthCounter(t *testing.T) {
 	bwc := NewBandwidthCounter()
-	start := make(chan struct{})
+	for i := 0; i < 40; i++ {
-	var wg sync.WaitGroup
+		for i := 0; i < 100; i++ {
-	wg.Add(200)
+			p := peer.ID(fmt.Sprintf("peer-%d", i))
-	for i := 0; i < 100; i++ {
+			for j := 0; j < 2; j++ {
-		p := peer.ID(fmt.Sprintf("peer-%d", i))
+				proto := protocol.ID(fmt.Sprintf("proto-%d", j))
-		for j := 0; j < 2; j++ {
-			proto := protocol.ID(fmt.Sprintf("proto-%d", j))
-			go func() {
-				defer wg.Done()
 
 				// make sure the bandwidth counters are active
 				bwc.LogSentMessage(100)
@@ -70,27 +72,15 @@ func TestBandwidthCounter(t *testing.T) {
 				bwc.LogSentMessageStream(100, proto, p)
 				bwc.LogRecvMessageStream(50, proto, p)
 
-				<-start
+				// <-start
-
+			}
-				t := time.NewTicker(100 * time.Millisecond)
-				defer t.Stop()
-
-				for i := 0; i < 39; i++ {
-					bwc.LogSentMessage(100)
-					bwc.LogRecvMessage(50)
-					bwc.LogSentMessageStream(100, proto, p)
-					bwc.LogRecvMessageStream(50, proto, p)
-					<-t.C
-				}
-			}()
 		}
+		cl.Add(100 * time.Millisecond)
 	}
 
 	assertProtocols := func(check func(Stats)) {
 		byProtocol := bwc.GetBandwidthByProtocol()
-		if len(byProtocol) != 2 {
+		require.Len(t, byProtocol, 2, "expected 2 protocols")
-			t.Errorf("expected 2 protocols, got %d", len(byProtocol))
-		}
 		for i := 0; i < 2; i++ {
 			p := protocol.ID(fmt.Sprintf("proto-%d", i))
 			for _, stats := range [...]Stats{bwc.GetBandwidthForProtocol(p), byProtocol[p]} {
@@ -101,9 +91,7 @@ func TestBandwidthCounter(t *testing.T) {
 
 	assertPeers := func(check func(Stats)) {
 		byPeer := bwc.GetBandwidthByPeer()
-		if len(byPeer) != 100 {
+		require.Len(t, byPeer, 100, "expected 100 peers")
-			t.Errorf("expected 100 peers, got %d", len(byPeer))
-		}
 		for i := 0; i < 100; i++ {
 			p := peer.ID(fmt.Sprintf("peer-%d", i))
 			for _, stats := range [...]Stats{bwc.GetBandwidthForPeer(p), byPeer[p]} {
@@ -112,34 +100,22 @@ func TestBandwidthCounter(t *testing.T) {
 		}
 	}
 
-	time.Sleep(time.Second)
-	close(start)
-
-	wg.Wait()
-	time.Sleep(1 * time.Second)
-
 	assertPeers(func(stats Stats) {
-		assertEq(t, 8000, stats.TotalOut)
+		require.Equal(t, int64(8000), stats.TotalOut)
-		assertEq(t, 4000, stats.TotalIn)
+		require.Equal(t, int64(4000), stats.TotalIn)
 	})
 
 	assertProtocols(func(stats Stats) {
-		assertEq(t, 400000, stats.TotalOut)
+		require.Equal(t, int64(400000), stats.TotalOut)
-		assertEq(t, 200000, stats.TotalIn)
+		require.Equal(t, int64(200000), stats.TotalIn)
 	})
 
-	{
+	stats := bwc.GetBandwidthTotals()
-		stats := bwc.GetBandwidthTotals()
+	require.Equal(t, int64(800000), stats.TotalOut)
-		assertEq(t, 800000, stats.TotalOut)
+	require.Equal(t, int64(400000), stats.TotalIn)
-		assertEq(t, 400000, stats.TotalIn)
-	}
 }
 
 func TestResetBandwidthCounter(t *testing.T) {
-	if runtime.GOOS != "linux" {
-		// Specifically, it fails on MacOS because we need a high precision timer.
-		t.Skip("this test is highly timing dependent and only passes reliably on Linux")
-	}
 	bwc := NewBandwidthCounter()
 
 	p := peer.ID("peer-0")
@@ -151,69 +127,44 @@ func TestResetBandwidthCounter(t *testing.T) {
 	bwc.LogSentMessageStream(100, proto, p)
 	bwc.LogRecvMessageStream(50, proto, p)
 
-	time.Sleep(1*time.Second + time.Millisecond)
+	time.Sleep(200 * time.Millisecond) // make sure the meters are registered with the sweeper
+	cl.Add(time.Second)
 
 	bwc.LogSentMessage(42)
 	bwc.LogRecvMessage(24)
 	bwc.LogSentMessageStream(100, proto, p)
 	bwc.LogRecvMessageStream(50, proto, p)
 
-	time.Sleep(1*time.Second + time.Millisecond)
+	cl.Add(time.Second)
 
 	{
 		stats := bwc.GetBandwidthTotals()
-		assertEq(t, 84, stats.TotalOut)
+		require.Equal(t, int64(84), stats.TotalOut)
-		assertEq(t, 48, stats.TotalIn)
+		require.Equal(t, int64(48), stats.TotalIn)
 	}
 
 	{
 		stats := bwc.GetBandwidthByProtocol()
-		assertApproxEq(t, 1, float64(len(stats)))
+		require.Len(t, stats, 1)
 		stat := stats[proto]
-		assertApproxEq(t, 100, stat.RateOut)
+		require.Equal(t, float64(100), stat.RateOut)
-		assertApproxEq(t, 50, stat.RateIn)
+		require.Equal(t, float64(50), stat.RateIn)
 	}
 
 	{
 		stats := bwc.GetBandwidthByPeer()
-		assertApproxEq(t, 1, float64(len(stats)))
+		require.Len(t, stats, 1)
 		stat := stats[p]
-		assertApproxEq(t, 100, stat.RateOut)
+		require.Equal(t, float64(100), stat.RateOut)
-		assertApproxEq(t, 50, stat.RateIn)
+		require.Equal(t, float64(50), stat.RateIn)
 	}
 
 	bwc.Reset()
 	{
 		stats := bwc.GetBandwidthTotals()
-		assertEq(t, 0, stats.TotalOut)
+		require.Zero(t, stats.TotalOut)
-		assertEq(t, 0, stats.TotalIn)
+		require.Zero(t, stats.TotalIn)
-	}
+		require.Empty(t, bwc.GetBandwidthByProtocol(), "expected 0 protocols")
-
+		require.Empty(t, bwc.GetBandwidthByPeer(), "expected 0 peers")
-	{
-		byProtocol := bwc.GetBandwidthByProtocol()
-		if len(byProtocol) != 0 {
-			t.Errorf("expected 0 protocols, got %d", len(byProtocol))
-		}
-	}
-
-	{
-		byPeer := bwc.GetBandwidthByPeer()
-		if len(byPeer) != 0 {
-			t.Errorf("expected 0 peers, got %d", len(byPeer))
-		}
-	}
-}
-
-func assertEq(t *testing.T, expected, actual int64) {
-	if expected != actual {
-		t.Errorf("expected  %d, got %d", expected, actual)
-	}
-}
-
-func assertApproxEq(t *testing.T, expected, actual float64) {
-	t.Helper()
-	margin := expected * acceptableError
-	if !(math.Abs(expected-actual) <= margin) {
-		t.Errorf("expected %f (±%f), got %f", expected, margin, actual)
 	}
 }