feat(connext): log created outgoing hashlock xfers

This handles the http request xud receives from connext when an outgoing
hash lock transfer is created by logging an appropriate message.
Previously this would be logged as a `warn` due to an unknown incoming
transfer.

lib/connextclient/ConnextClient.ts

@@ -91,11 +91,14 @@ class ConnextClient extends SwapClient {
   public address?: string;
   /** A map of currency symbols to token addresses. */
   public tokenAddresses = new Map<string, string>();
-  /** A map of expected invoices by hash.
+  /**
+   * A map of expected invoices by hash.
    * This is equivalent to invoices of lnd with the difference
    * being that we're managing the state of invoice on xud level.
    */
   private expectedIncomingTransfers = new Map<string, ExpectedIncomingTransfer>();
+  /** The set of hashes for outgoing transfers. */
+  private outgoingTransferHashes = new Set<string>();
   private port: number;
   private host: string;
   private webhookport: number;
@@ -146,11 +149,18 @@ class ConnextClient extends SwapClient {
       timelock,
       rHash,
     } = transferReceivedRequest;
+
+    if (this.outgoingTransferHashes.has(rHash)) {
+      this.outgoingTransferHashes.delete(rHash);
+      this.logger.debug(`outgoing hash lock transfer with rHash ${rHash} created`);
+      return;
+    }
     const expectedIncomingTransfer = this.expectedIncomingTransfers.get(rHash);
     if (!expectedIncomingTransfer) {
       this.logger.warn(`received unexpected incoming transfer created event with rHash ${rHash}`);
       return;
     }
+
     const {
       units: expectedUnits,
       expiry: expectedTimelock,
@@ -588,6 +598,7 @@ class ConnextClient extends SwapClient {
    */
   private executeHashLockTransfer = async (payload: TokenPaymentRequest): Promise<string> => {
     this.logger.debug(`sending payment of ${payload.amount} with hash ${payload.lockHash} to ${payload.recipient}`);
+    this.outgoingTransferHashes.add(payload.lockHash);
     const res = await this.sendRequest('/hashlock-transfer', 'POST', payload);
     const { appId } = await parseResponseBody<ConnextTransferResponse>(res);
     return appId;