Merge pull request #1193 from ydb-platform/last-usage

moved internal/conn.lastUsage into internal/xsync package

Author: asmyasnikov

internal/conn/conn.go

@@ -19,6 +19,7 @@ import (
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/stack"
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xcontext"
 	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xerrors"
+	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xsync"
 	"github.com/ydb-platform/ydb-go-sdk/v3/trace"
 )
 
@@ -55,8 +56,8 @@ type conn struct {
 	endpoint          endpoint.Endpoint // ro access
 	closed            bool
 	state             atomic.Uint32
-	lastUsage         *lastUsage
 	childStreams      *xcontext.CancelsGuard
+	lastUsage         xsync.LastUsage
 	onClose           []func(*conn)
 	onTransportErrors []func(ctx context.Context, cc Conn, cause error)
 }
@@ -504,7 +505,7 @@ func newConn(e endpoint.Endpoint, config Config, opts ...option) *conn {
 		endpoint:     e,
 		config:       config,
 		done:         make(chan struct{}),
-		lastUsage:    newLastUsage(nil),
+		lastUsage:    xsync.NewLastUsage(),
 		childStreams: xcontext.NewCancelsGuard(),
 		onClose: []func(*conn){
 			func(c *conn) {

internal/conn/last_usage.go

@@ -0,0 +1,62 @@
+package xsync
+
+import (
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/jonboulle/clockwork"
+)
+
+type (
+	LastUsage interface {
+		Get() time.Time
+		Start() (stop func())
+	}
+	lastUsage struct {
+		locks atomic.Int64
+		t     atomic.Pointer[time.Time]
+		clock clockwork.Clock
+	}
+	lastUsageOption func(g *lastUsage)
+)
+
+func WithClock(clock clockwork.Clock) lastUsageOption {
+	return func(g *lastUsage) {
+		g.clock = clock
+	}
+}
+
+func NewLastUsage(opts ...lastUsageOption) *lastUsage {
+	lastUsage := &lastUsage{
+		clock: clockwork.NewRealClock(),
+	}
+	for _, opt := range opts {
+		opt(lastUsage)
+	}
+
+	now := lastUsage.clock.Now()
+
+	lastUsage.t.Store(&now)
+
+	return lastUsage
+}
+
+func (g *lastUsage) Get() time.Time {
+	if g.locks.Load() == 0 {
+		return *g.t.Load()
+	}
+
+	return g.clock.Now()
+}
+
+func (g *lastUsage) Start() (stop func()) {
+	g.locks.Add(1)
+
+	return sync.OnceFunc(func() {
+		if g.locks.Add(-1) == 0 {
+			now := g.clock.Now()
+			g.t.Store(&now)
+		}
+	})
+}

internal/xsync/last_usage_guard.go

@@ -1,4 +1,4 @@
-package conn
+package xsync
 
 import (
 	"testing"
@@ -8,7 +8,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func Test_lastUsage_Lock(t *testing.T) {
+func TestLastUsageGuardLock(t *testing.T) {
 	t.Run("NowFromLocked", func(t *testing.T) {
 		start := time.Unix(0, 0)
 		clock := clockwork.NewFakeClockAt(start)