Bugfix: timeout error crashing explorer

app/platform/fabric/gateway/FabricGateway.ts

@@ -434,13 +434,26 @@ export class FabricGateway {
 			if (!this.waitingResp) {
 				this.waitingResp = true;
 				logger.info('Sending discovery request...');
-				await this.ds.send({
-					asLocalhost: this.asLocalhost,
-					requestTimeout: 5000,
-					refreshAge: 15000,
-					targets: this.dsTargets
-				});
-				logger.info('Succeeded to send discovery request');
+				await this.ds
+          .send({
+            asLocalhost: this.asLocalhost,
+            requestTimeout: 5000,
+            refreshAge: 15000,
+            targets: this.dsTargets,
+          })
+          .then(() => {
+            logger.info('Succeeded to send discovery request');
+          })
+          .catch(error => {
+            if (error) {
+              logger.warn(
+                'Failed to send discovery request for channel',
+                error,
+              );
+              this.waitingResp = false;
+              this.ds.close();
+            }
+          });
 			} else {
 				logger.info('Have already been sending a request');
 				return null;

app/platform/fabric/sync/SyncService.ts

@@ -360,6 +360,15 @@ export class SyncServices {
 	async syncBlocks(client, channel_name) {
 		const network_id = client.getNetworkId();
 
+    // Get channel information from ledger
+    const channelInfo = await client.fabricGateway.queryChainInfo(channel_name);
+
+    if (!channelInfo) {
+      logger.info(
+        `syncBlocks: Failed to retrieve channelInfo >> ${channel_name}`,
+      );
+      return;
+    }
 		const synch_key = `${network_id}_${channel_name}`;
 		logger.info(`syncBlocks: Start >> ${synch_key}`);
 		if (this.synchInProcess.includes(synch_key)) {
@@ -368,8 +377,6 @@ export class SyncServices {
 		}
 		this.synchInProcess.push(synch_key);
 
-		// Get channel information from ledger
-		const channelInfo = await client.fabricGateway.queryChainInfo(channel_name);
 		const channel_genesis_hash = client.getChannelGenHash(channel_name);
 		const blockHeight = parseInt(channelInfo.height.low) - 1;
 		// Query missing blocks from DB

app/sync.ts

@@ -58,7 +58,10 @@ process.on('unhandledRejection', (up : {message : string}) => {
 	} else {
 		logger.error(up);
 	}
-	shutDown();
+  // prevent timeout error from calling shutdown
+	if (!up.message.includes('REQUEST TIMEOUT')) {
+    shutDown();
+  }
 });
 process.on('uncaughtException', up => {
 	logger.error(

app/test/FabricGateway.test.ts

@@ -10,6 +10,7 @@ import sinon from 'sinon';
 import { FabricGateway } from '../platform/fabric/gateway/FabricGateway';
 
 // DiscoveryService (this.ds)
+const stubSend = sinon.stub();
 const stubSign = sinon.stub();
 const stubGetDiscoveryResults = sinon.stub();
 const stubClose = sinon.stub();
@@ -35,7 +36,7 @@ function getFabricGatewayInstance() {
 					return {
 						build: sinon.stub(),
 						sign: stubSign,
-						send: sinon.stub(),
+						send: stubSend,
 						getDiscoveryResults: stubGetDiscoveryResults,
 						close: stubClose
 					};
@@ -91,6 +92,7 @@ function getFabricGatewayInstance() {
 
 function resetAllStubs() {
 	// DiscoveryService (this.ds)
+  stubSend.reset();
 	stubSign.reset();
 	stubGetDiscoveryResults.reset();
 	stubClose.reset();
@@ -173,18 +175,25 @@ describe('sendDiscoveryRequest', () => {
 		resetAllStubs();
 	});
 
+  it('should throw error when discoveryService.sends() throw error', async () => {
+    stubSend.rejects(Promise.reject(new Error('REQUEST TIMEOUT')));
+    await gw.sendDiscoveryRequest();
+    expect(stubWarn.called).be.equal(true);
+    expect(stubClose.calledOnce).be.equal(true);
+  });
+
+  it('should throw error when failed to call getDiscoveryResults()', async () => {
+    stubGetDiscoveryResults.throws();
+    await gw.sendDiscoveryRequest();
+    expect(stubWarn.called).be.equal(true);
+    expect(stubClose.calledOnce).be.equal(true);
+  });
+
 	it('should return without error', async () => {
 		stubGetDiscoveryResults.returns(Promise.resolve());
 		await gw.sendDiscoveryRequest();
 		expect(stubError.called).be.equal(false);
 	});
-
-	it('should throw error when failed to call getDiscoveryResults()', async () => {
-		stubGetDiscoveryResults.throws();
-		await gw.sendDiscoveryRequest();
-		expect(stubWarn.called).be.equal(true);
-		expect(stubClose.calledOnce).be.equal(true);
-	});
 });
 
 describe('getDiscoveryResult', () => {