arkd-wallet: unit tests outpointLocker

pkg/arkd-wallet/core/application/wallet/key_manager.go

@@ -67,7 +67,7 @@ func newKeyManager(seed []byte, network *chaincfg.Params) (*keyManager, error) {
 		return nil, err
 	}
 
-	forfeitPrvkey, err := deriveForfeitPrvkey(mainAccount, network)
+	forfeitPrvkey, err := deriveForfeitPrvkey(mainAccount)
 	if err != nil {
 		return nil, err
 	}
@@ -114,7 +114,7 @@ func computeTaprootDerivationScheme(accountKey *hdkeychain.ExtendedKey) (string,
 	return neutered.String() + "-[taproot]", nil
 }
 
-func deriveForfeitPrvkey(xpub *hdkeychain.ExtendedKey, network *chaincfg.Params) (*btcec.PrivateKey, error) {
+func deriveForfeitPrvkey(xpub *hdkeychain.ExtendedKey) (*btcec.PrivateKey, error) {
 	key, err := xpub.Derive(0)
 	if err != nil {
 		return nil, err

pkg/arkd-wallet/core/application/wallet/outpoint_locker.go

@@ -2,6 +2,7 @@ package wallet
 
 import (
 	"context"
+	"fmt"
 	"sync"
 	"time"
 
@@ -23,20 +24,35 @@ func newOutpointLocker(lockFor time.Duration) *outpointLocker {
 }
 
 func (l *outpointLocker) lock(ctx context.Context, outpoints ...wire.OutPoint) error {
+	if len(outpoints) == 0 {
+		return nil
+	}
+
+	lockedOutpoints, err := l.get(ctx)
+	if err != nil {
+		return err
+	}
+
 	l.locker.Lock()
 	defer l.locker.Unlock()
 
 	now := time.Now()
 	lockedUntil := now.Add(l.lockExpiry)
 
+	for _, outpoint := range outpoints {
+		if _, isLocked := lockedOutpoints[outpoint]; isLocked {
+			return fmt.Errorf("outpoint %s is already locked", outpoint)
+		}
+	}
+
 	for _, outpoint := range outpoints {
 		l.lockedOutpoints[outpoint] = lockedUntil
 	}
 
 	return nil
 }
 
-func (l *outpointLocker) get(ctx context.Context) (map[wire.OutPoint]struct{}, error) {
+func (l *outpointLocker) get(_ context.Context) (map[wire.OutPoint]struct{}, error) {
 	l.locker.Lock()
 	defer l.locker.Unlock()
 

pkg/arkd-wallet/core/application/wallet/outpoint_locker_test.go

@@ -0,0 +1,141 @@
+package wallet
+
+import (
+	"crypto/rand"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/btcsuite/btcd/wire"
+	"github.com/stretchr/testify/require"
+)
+
+func TestOutpointLocker(t *testing.T) {
+	t.Run("new", func(t *testing.T) {
+		lockDuration := 5 * time.Minute
+		locker := newOutpointLocker(lockDuration)
+
+		require.NotNil(t, locker)
+		require.Equal(t, lockDuration, locker.lockExpiry)
+		require.NotNil(t, locker.lockedOutpoints)
+		require.Empty(t, locker.lockedOutpoints)
+	})
+
+	t.Run("lock", func(t *testing.T) {
+		lockDuration := 1 * time.Hour
+		locker := newOutpointLocker(lockDuration)
+
+		outpoint1 := wire.OutPoint{Hash: random32Bytes(), Index: 0}
+		outpoint2 := wire.OutPoint{Hash: random32Bytes(), Index: 1}
+
+		// test locking single outpoint
+		err := locker.lock(t.Context(), outpoint1)
+		require.NoError(t, err)
+
+		// verify outpoint is locked
+		lockedOutpoints, err := locker.get(t.Context())
+		require.NoError(t, err)
+		require.Len(t, lockedOutpoints, 1)
+		require.Contains(t, lockedOutpoints, outpoint1)
+
+		// test locking multiple outpoints
+		err = locker.lock(t.Context(), outpoint2)
+		require.NoError(t, err)
+
+		// verify both outpoints are locked
+		lockedOutpoints, err = locker.get(t.Context())
+		require.NoError(t, err)
+		require.Len(t, lockedOutpoints, 2)
+		require.Contains(t, lockedOutpoints, outpoint1)
+		require.Contains(t, lockedOutpoints, outpoint2)
+
+		// test locking same outpoint again
+		time.Sleep(10 * time.Millisecond)
+		err = locker.lock(t.Context(), outpoint1)
+		require.ErrorContains(t, err, "already locked")
+
+		// verify outpoint is still locked with updated expiry
+		lockedOutpoints, err = locker.get(t.Context())
+		require.NoError(t, err)
+		require.Len(t, lockedOutpoints, 2)
+		require.Contains(t, lockedOutpoints, outpoint1)
+		require.Contains(t, lockedOutpoints, outpoint2)
+	})
+
+	t.Run("lock and unlock", func(t *testing.T) {
+		lockDuration := 100 * time.Millisecond
+		locker := newOutpointLocker(lockDuration)
+
+		outpoint1 := wire.OutPoint{Hash: random32Bytes(), Index: 0}
+		outpoint2 := wire.OutPoint{Hash: random32Bytes(), Index: 1}
+
+		// lock outpoints
+		err := locker.lock(t.Context(), outpoint1, outpoint2)
+		require.NoError(t, err)
+
+		lockedOutpoints, err := locker.get(t.Context())
+		require.NoError(t, err)
+		require.Len(t, lockedOutpoints, 2)
+		require.Contains(t, lockedOutpoints, outpoint1)
+		require.Contains(t, lockedOutpoints, outpoint2)
+
+		// wait for locks to expire
+		time.Sleep(lockDuration + 50*time.Millisecond)
+
+		lockedOutpoints, err = locker.get(t.Context())
+		require.NoError(t, err)
+		require.Empty(t, lockedOutpoints)
+	})
+}
+
+func TestOutpointLocker_ConcurrentGetAndLock(t *testing.T) {
+	// half lock, half get
+	numberOfRoutines := 100
+	lockDuration := 100 * time.Millisecond
+	locker := newOutpointLocker(lockDuration)
+
+	outpoints := make([]wire.OutPoint, 0, numberOfRoutines/2)
+	for index := range numberOfRoutines / 2 {
+		outpoints = append(outpoints, wire.OutPoint{Hash: random32Bytes(), Index: uint32(index)})
+	}
+
+	wg := sync.WaitGroup{}
+	wg.Add(numberOfRoutines)
+
+	go func() {
+		// start one half of goroutines that lock the outpoint
+		for _, outpoint := range outpoints {
+			go func(outpoint wire.OutPoint) {
+				err := locker.lock(t.Context(), outpoint)
+				require.NoError(t, err)
+				wg.Done()
+			}(outpoint)
+		}
+	}()
+
+	go func() {
+		// start the other half of goroutines that get locked outpoints
+		for range numberOfRoutines / 2 {
+			go func() {
+				_, err := locker.get(t.Context())
+				require.NoError(t, err)
+				wg.Done()
+			}()
+		}
+	}()
+
+	wg.Wait()
+
+	lockedOutpoints, err := locker.get(t.Context())
+	require.NoError(t, err)
+	require.Len(t, lockedOutpoints, len(outpoints))
+	for _, outpoint := range outpoints {
+		require.Contains(t, lockedOutpoints, outpoint)
+	}
+}
+
+func random32Bytes() [32]byte {
+	var b [32]byte
+	rand.Read(b[:])
+	return b
+}