implements DiscardTransaction(), required for #32

cmd/status/library.go

@@ -158,6 +158,25 @@ func CompleteTransaction(id, password *C.char) *C.char {
 	return C.CString(string(outBytes))
 }
 
+//export DiscardTransaction
+func DiscardTransaction(id *C.char) *C.char {
+	err := geth.DiscardTransaction(C.GoString(id))
+
+	errString := ""
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		errString = err.Error()
+	}
+
+	out := geth.DiscardTransactionResult{
+		Id:    C.GoString(id),
+		Error: errString,
+	}
+	outBytes, _ := json.Marshal(&out)
+
+	return C.CString(string(outBytes))
+}
+
 //export StartNode
 func StartNode(datadir *C.char) *C.char {
 	// This starts a geth node with the given datadir

geth/txqueue.go

@@ -27,10 +27,11 @@ const (
 	MessageIdKey           = "message_id"
 
 	// tx error codes
-	SendTransactionNoErrorCode       = "0"
-	SendTransactionDefaultErrorCode  = "1"
-	SendTransactionPasswordErrorCode = "2"
-	SendTransactionTimeoutErrorCode  = "3"
+	SendTransactionNoErrorCode        = "0"
+	SendTransactionDefaultErrorCode   = "1"
+	SendTransactionPasswordErrorCode  = "2"
+	SendTransactionTimeoutErrorCode   = "3"
+	SendTransactionDiscardedErrorCode = "4"
 )
 
 func onSendTransactionRequest(queuedTx status.QueuedTx) {
@@ -47,11 +48,16 @@ func onSendTransactionRequest(queuedTx status.QueuedTx) {
 	C.StatusServiceSignalEvent(C.CString(string(body)))
 }
 
-func onSendTransactionReturn(queuedTx status.QueuedTx, err error) {
+func onSendTransactionReturn(queuedTx *status.QueuedTx, err error) {
 	if err == nil {
 		return
 	}
 
+	// discard notifications with empty tx
+	if queuedTx == nil {
+		return
+	}
+
 	// error occurred, signal up to application
 	event := GethEvent{
 		Type: EventTransactionFailed,
@@ -73,15 +79,16 @@ func sendTransactionErrorCode(err error) string {
 		return SendTransactionNoErrorCode
 	}
 
-	if err == accounts.ErrDecrypt {
+	switch err {
+	case accounts.ErrDecrypt:
 		return SendTransactionPasswordErrorCode
-	}
-
-	if err == status.ErrQueuedTxTimedOut {
+	case status.ErrQueuedTxTimedOut:
 		return SendTransactionTimeoutErrorCode
+	case status.ErrQueuedTxDiscarded:
+		return SendTransactionDiscardedErrorCode
+	default:
+		return SendTransactionDefaultErrorCode
 	}
-
-	return SendTransactionDefaultErrorCode
 }
 
 func CompleteTransaction(id, password string) (common.Hash, error) {
@@ -95,6 +102,17 @@ func CompleteTransaction(id, password string) (common.Hash, error) {
 	return backend.CompleteQueuedTransaction(status.QueuedTxId(id), password)
 }
 
+func DiscardTransaction(id string) error {
+	lightEthereum, err := GetNodeManager().LightEthereumService()
+	if err != nil {
+		return err
+	}
+
+	backend := lightEthereum.StatusBackend
+
+	return backend.DiscardQueuedTransaction(status.QueuedTxId(id))
+}
+
 func messageIdFromContext(ctx context.Context) string {
 	if ctx == nil {
 		return ""

geth/txqueue_test.go

@@ -257,6 +257,147 @@ func TestDoubleCompleteQueuedTransactions(t *testing.T) {
 	time.Sleep(5 * time.Second)
 }
 
+func TestDiscardQueuedTransactions(t *testing.T) {
+	err := geth.PrepareTestNode()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	accountManager, err := geth.GetNodeManager().AccountManager()
+	if err != nil {
+		t.Errorf(err.Error())
+		return
+	}
+
+	// create an account
+	address, _, _, err := geth.CreateAccount(newAccountPassword)
+	if err != nil {
+		t.Errorf("could not create account: %v", err)
+		return
+	}
+
+	// obtain reference to status backend
+	lightEthereum, err := geth.GetNodeManager().LightEthereumService()
+	if err != nil {
+		t.Errorf("Test failed: LES service is not running: %v", err)
+		return
+	}
+	backend := lightEthereum.StatusBackend
+
+	// reset queue
+	backend.TransactionQueue().Reset()
+
+	// make sure you panic if transaction complete doesn't return
+	completeQueuedTransaction := make(chan struct{}, 1)
+	geth.PanicAfter(20*time.Second, completeQueuedTransaction, "TestDiscardQueuedTransactions")
+
+	// replace transaction notification handler
+	var txId string
+	txFailedEventCalled := false
+	geth.SetDefaultNodeNotificationHandler(func(jsonEvent string) {
+		var envelope geth.GethEvent
+		if err := json.Unmarshal([]byte(jsonEvent), &envelope); err != nil {
+			t.Errorf("cannot unmarshal event's JSON: %s", jsonEvent)
+			return
+		}
+		if envelope.Type == geth.EventTransactionQueued {
+			event := envelope.Event.(map[string]interface{})
+			txId = event["id"].(string)
+			t.Logf("transaction queued (will be discarded soon): {id: %s}\n", txId)
+
+			if !backend.TransactionQueue().Has(status.QueuedTxId(txId)) {
+				t.Errorf("txqueue should still have test tx: %s", txId)
+				return
+			}
+
+			// discard
+			err := geth.DiscardTransaction(txId)
+			if err != nil {
+				t.Errorf("cannot discard tx: %v", err)
+				return
+			}
+
+			// try completing discarded transaction
+			_, err = geth.CompleteTransaction(txId, testAddressPassword)
+			if err.Error() != "transaction hash not found" {
+				t.Error("expects tx not found, but call to CompleteTransaction succeeded")
+				return
+			}
+
+			time.Sleep(1 * time.Second) // make sure that tx complete signal propagates
+			if backend.TransactionQueue().Has(status.QueuedTxId(txId)) {
+				t.Errorf("txqueue should not have test tx at this point (it should be discarded): %s", txId)
+				return
+			}
+
+			completeQueuedTransaction <- struct{}{} // so that timeout is aborted
+		}
+
+		if envelope.Type == geth.EventTransactionFailed {
+			event := envelope.Event.(map[string]interface{})
+			t.Logf("transaction return event received: {id: %s}\n", event["id"].(string))
+
+			receivedErrMessage := event["error_message"].(string)
+			expectedErrMessage := status.ErrQueuedTxDiscarded.Error()
+			if receivedErrMessage != expectedErrMessage {
+				t.Errorf("unexpected error message received: got %v", receivedErrMessage)
+				return
+			}
+
+			receivedErrCode := event["error_code"].(string)
+			if receivedErrCode != geth.SendTransactionDiscardedErrorCode {
+				t.Errorf("unexpected error code received: got %v", receivedErrCode)
+				return
+			}
+
+			txFailedEventCalled = true
+		}
+	})
+
+	// send from the same test account (which is guaranteed to have ether)
+	from, err := utils.MakeAddress(accountManager, testAddress)
+	if err != nil {
+		t.Errorf("could not retrieve account from address: %v", err)
+		return
+	}
+
+	to, err := utils.MakeAddress(accountManager, address)
+	if err != nil {
+		t.Errorf("could not retrieve account from address: %v", err)
+		return
+	}
+
+	//  this call blocks, and should return when DiscardQueuedTransaction() is called
+	txHashCheck, err := backend.SendTransaction(nil, status.SendTxArgs{
+		From:  from.Address,
+		To:    &to.Address,
+		Value: rpc.NewHexNumber(big.NewInt(1000000000000)),
+	})
+	if err != status.ErrQueuedTxDiscarded {
+		t.Errorf("expeced error not thrown: %v", err)
+		return
+	}
+
+	if !reflect.DeepEqual(txHashCheck, common.Hash{}) {
+		t.Error("transaction returned hash, while it shouldn't")
+		return
+	}
+
+	if backend.TransactionQueue().Count() != 0 {
+		t.Error("tx queue must be empty at this point")
+		return
+	}
+
+	if !txFailedEventCalled {
+		t.Error("expected tx failure signal is not received")
+		return
+	}
+
+	t.Log("sleep extra time, to allow sync")
+	time.Sleep(5 * time.Second)
+}
+
 func TestNonExistentQueuedTransactions(t *testing.T) {
 	err := geth.PrepareTestNode()
 	if err != nil {

geth/types.go

@@ -53,6 +53,11 @@ type CompleteTransactionResult struct {
 	Error string `json:"error"`
 }
 
+type DiscardTransactionResult struct {
+	Id    string `json:"id"`
+	Error string `json:"error"`
+}
+
 type GethEvent struct {
 	Type  string      `json:"type"`
 	Event interface{} `json:"event"`

vendor/github.com/ethereum/go-ethereum/internal/ethapi/api.go

@@ -1028,19 +1028,26 @@ func (s *PublicTransactionPoolAPI) SendTransaction(ctx context.Context, args Sen
 		Context: ctx,
 		Args:    status.SendTxArgs(args),
 		Done:    make(chan struct{}, 1),
+		Discard: make(chan struct{}, 1),
 	}
 
 	// send transaction to pending pool
 	s.txQueue <- queuedTx
 
-	// now wait up until transaction is complete (via call to CompleteQueuedTransaction) or timeout occurs
+	// now wait up until transaction is:
+	// - completed (via CompleteQueuedTransaction),
+	// - discarded (via DiscardQueuedTransaction)
+	// - or times out
 	backend := GetStatusBackend()
 	select {
 	case <-queuedTx.Done:
-		backend.NotifyOnQueuedTxReturn(queuedTx.Id, queuedTx.Err)
+		backend.NotifyOnQueuedTxReturn(queuedTx, queuedTx.Err)
+		return queuedTx.Hash, queuedTx.Err
+	case <-queuedTx.Discard:
+		backend.NotifyOnQueuedTxReturn(queuedTx, status.ErrQueuedTxDiscarded)
 		return queuedTx.Hash, queuedTx.Err
 	case <-time.After(status.DefaultTxSendCompletionTimeout * time.Second):
-		backend.NotifyOnQueuedTxReturn(queuedTx.Id, status.ErrQueuedTxTimedOut)
+		backend.NotifyOnQueuedTxReturn(queuedTx, status.ErrQueuedTxTimedOut)
 		return common.Hash{}, status.ErrQueuedTxTimedOut
 	}
 

vendor/github.com/ethereum/go-ethereum/internal/ethapi/status_backend.go

@@ -47,12 +47,12 @@ func GetStatusBackend() *StatusBackend {
 	return statusBackend
 }
 
-func (b *StatusBackend) NotifyOnQueuedTxReturn(id status.QueuedTxId, err error) {
+func (b *StatusBackend) NotifyOnQueuedTxReturn(queuedTx *status.QueuedTx, err error) {
 	if b == nil {
 		return
 	}
 
-	b.txQueue.NotifyOnQueuedTxReturn(id, err)
+	b.txQueue.NotifyOnQueuedTxReturn(queuedTx, err)
 }
 
 func (b *StatusBackend) SetTransactionReturnHandler(fn status.EnqueuedTxReturnHandler) {
@@ -95,7 +95,7 @@ func (b *StatusBackend) CompleteQueuedTransaction(id status.QueuedTxId, passphra
 
 	// on password error, notify the app, and keep tx in queue (so that CompleteQueuedTransaction() can be resent)
 	if err == accounts.ErrDecrypt {
-		b.NotifyOnQueuedTxReturn(id, err)
+		b.NotifyOnQueuedTxReturn(queuedTx, err)
 		return hash, err // SendTransaction is still blocked
 	}
 
@@ -107,6 +107,23 @@ func (b *StatusBackend) CompleteQueuedTransaction(id status.QueuedTxId, passphra
 	return hash, err
 }
 
+// DiscardQueuedTransaction discards queued transaction forcing SendTransaction to return
+func (b *StatusBackend) DiscardQueuedTransaction(id status.QueuedTxId) error {
+	queuedTx, err := b.txQueue.Get(id)
+	if err != nil {
+		return err
+	}
+
+	// remove from queue, before notifying SendTransaction
+	b.TransactionQueue().Remove(queuedTx.Id)
+
+	// allow SendTransaction to return
+	queuedTx.Err = status.ErrQueuedTxDiscarded
+	queuedTx.Discard <- struct{}{} // sendTransaction() waits on this, notify so that it can return
+
+	return nil
+}
+
 func (b *StatusBackend) transactionQueueForwardingLoop() {
 	txQueue, err := b.txapi.GetTransactionQueue()
 	if err != nil {

vendor/github.com/ethereum/go-ethereum/les/status/txqueue.go

@@ -19,6 +19,7 @@ const (
 var (
 	ErrQueuedTxIdNotFound = errors.New("transaction hash not found")
 	ErrQueuedTxTimedOut   = errors.New("transaction sending timed out")
+	ErrQueuedTxDiscarded  = errors.New("transaction has been discarded")
 )
 
 // TxQueue is capped container that holds pending transactions
@@ -42,6 +43,7 @@ type QueuedTx struct {
 	Context context.Context
 	Args    SendTxArgs
 	Done    chan struct{}
+	Discard chan struct{}
 	Err     error
 }
 
@@ -51,7 +53,7 @@ type QueuedTxId string
 type EnqueuedTxHandler func(QueuedTx)
 
 // EnqueuedTxReturnHandler is a function that receives response when tx is complete (both on success and error)
-type EnqueuedTxReturnHandler func(queuedTx QueuedTx, err error)
+type EnqueuedTxReturnHandler func(queuedTx *QueuedTx, err error)
 
 // SendTxArgs represents the arguments to submbit a new transaction into the transaction pool.
 type SendTxArgs struct {
@@ -85,6 +87,15 @@ func (q *TxQueue) evictionLoop() {
 	}
 }
 
+// Reset is to be used in tests only, as it simply creates new transaction map, w/o any cleanup of the previous one
+func (q *TxQueue) Reset() {
+	q.mu.Lock()
+	defer q.mu.Unlock()
+
+	q.transactions = make(map[QueuedTxId]*QueuedTx)
+	q.evictableIds = make(chan QueuedTxId, DefaultTxQueueCap)
+}
+
 func (q *TxQueue) Enqueue(tx *QueuedTx) error {
 	if q.txEnqueueHandler == nil { //discard, until handler is provided
 		return nil
@@ -145,14 +156,19 @@ func (q *TxQueue) SetTxReturnHandler(fn EnqueuedTxReturnHandler) {
 	q.txReturnHandler = fn
 }
 
-func (q *TxQueue) NotifyOnQueuedTxReturn(id QueuedTxId, err error) {
+func (q *TxQueue) NotifyOnQueuedTxReturn(queuedTx *QueuedTx, err error) {
 	if q == nil {
 		return
 	}
 
+	// discard, if transaction is not found
+	if queuedTx == nil {
+		return
+	}
+
 	// on success, remove item from the queue and stop propagating
 	if err == nil {
-		q.Remove(id)
+		q.Remove(queuedTx.Id)
 		return
 	}
 
@@ -161,17 +177,11 @@ func (q *TxQueue) NotifyOnQueuedTxReturn(id QueuedTxId, err error) {
 		return
 	}
 
-	// discard, if transaction is not found
-	tx, _ := q.Get(id)
-	if tx == nil {
-		return
-	}
-
 	// remove from queue on any error (except for password related one) and propagate
 	if err != accounts.ErrDecrypt {
-		q.Remove(id)
+		q.Remove(queuedTx.Id)
 	}
 
 	// notify handler
-	q.txReturnHandler(*tx, err)
+	q.txReturnHandler(queuedTx, err)
 }