Added blockEvent handler

Signed-off-by: sapthasurendran <saptha.surendran@ibm.com>

asset-transfer-basic/rest-api-typescript/src/fabric.ts

@@ -12,7 +12,10 @@ import {
   TxEventHandler,
   TxEventHandlerFactory,
   Wallets,
-  Network
+  Network,
+  BlockListener,
+  BlockEvent,
+  TransactionEvent,
 } from 'fabric-network';
 import { Redis } from 'ioredis';
 import * as config from './config';
@@ -25,7 +28,6 @@ import {
   TransactionNotFoundError,
 } from './errors';
 
-
 export const getNetwork = async (gateway: Gateway): Promise<Network> => {
   const network = await gateway.getNetwork(config.channelName);
   return network;
@@ -354,3 +356,21 @@ const isDuplicateTransaction = (error: {
   return false;
 };
 
+export const blockEventHandler = (redis: Redis): BlockListener => {
+  const blockListner = async (event: BlockEvent) => {
+    logger.debug('Block event received ');
+    const transEvents: Array<TransactionEvent> = event.getTransactionEvents();
+
+    for (const transEvent of transEvents) {
+      if (transEvent && transEvent.isValid) {
+        logger.debug(
+          'Remove transation with txnId %s',
+          transEvent.transactionId
+        );
+        await clearTransactionDetails(redis, transEvent.transactionId);
+      }
+    }
+  };
+
+  return blockListner;
+};

asset-transfer-basic/rest-api-typescript/src/index.ts

@@ -2,10 +2,10 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import { Contract } from 'fabric-network';
+import { Contract, Network } from 'fabric-network';
 import { Redis } from 'ioredis';
 import * as config from './config';
-import { startRetryLoop } from './fabric';
+import { startRetryLoop, blockEventHandler } from './fabric';
 import { logger } from './logger';
 import { createServer } from './server';
 
@@ -14,6 +14,8 @@ async function main() {
 
   const contract: Contract = app.get('contracts').contract;
   const redis: Redis = app.get('redis');
+  const network: Network = app.get('network');
+  await network.addBlockListener(blockEventHandler(redis));
   startRetryLoop(contract, redis);
 
   app.listen(config.port, () => {

asset-transfer-basic/rest-api-typescript/src/server.ts

@@ -51,10 +51,10 @@ export const createServer = async (): Promise<Application> => {
 
   const gateway = await getGateway();
   const contracts = await getContracts(gateway);
-  const network = await getNetwork(gateway)
+  const network = await getNetwork(gateway);
   app.set('contracts', contracts);
   app.set('redis', redis);
-  app.set('network',network)
+  app.set('network', network);
 
   // Health routes
   app.get('/ready', (_req, res) =>