FABN-1050: Catch errors thrown by event callbacks

Catch (and log) any errors thrown by transaction and block
event listener onEvent and onError callbacks.

Change-Id: Ic0607b86b89cc7150ca372b1f14cac8652ccdc58
Signed-off-by: Mark S. Lewis <mark_lewis@uk.ibm.com>

fabric-client/lib/ChannelEventHub.js

@@ -1533,8 +1533,8 @@ class EventRegistration {
 	 *        setting if not option setting is set by the user
 	 */
 	constructor(onEvent, onError, options, default_unregister, default_disconnect) {
-		this.onEvent = onEvent;
-		this.onError = onError;
+		this._onEventFn = onEvent;
+		this._onErrorFn = onError;
 		this.unregister = default_unregister;
 		this.disconnect = default_disconnect;
 		this.unregister_action = () => { }; // do nothing by default
@@ -1556,4 +1556,20 @@ class EventRegistration {
 			}
 		}
 	}
+
+	onEvent(...args) {
+		try {
+			this._onEventFn(...args);
+		} catch (error) {
+			logger.warn('Event notification callback failed', error);
+		}
+	}
+
+	onError(...args) {
+		try {
+			this._onErrorFn(...args);
+		} catch (error) {
+			logger.warn('Error notifacation callback failed', error);
+		}
+	}
 }

fabric-client/test/ChannelEventHub.js

@@ -487,20 +487,48 @@ describe('ChannelEventHub', () => {
 	});
 
 	describe('#disconnect', () => {
+		let hub;
+
+		beforeEach(() => {
+			hub = new ChannelEventHub('channel', 'peer');
+		});
+
 		it('should call a debug log', () => {
-			const hub = new ChannelEventHub('channel', 'peer');
 			hub._disconnect_running = true;
 			hub.disconnect();
 			sinon.assert.calledWith(FakeLogger.debug, 'disconnect - disconnect is running');
 		});
 
 		it('should log, call _disconnect and change disconnect_running to false', () => {
-			const hub = new ChannelEventHub('channel', 'peer');
 			hub._disconnect = sandbox.stub();
 			hub.disconnect();
 			hub._disconnect_running.should.be.false;
 			sinon.assert.calledWith(hub._disconnect, sinon.match(Error));
 		});
+
+		it('handles errors thrown by block event listeners', () => {
+			const onEventStub = sandbox.stub().throws('onEvent');
+			const onErrorStub = sandbox.stub().throws('onError');
+			hub.registerBlockEvent(onEventStub, onErrorStub, {});
+			hub.registerBlockEvent(onEventStub, onErrorStub, {});
+
+			hub.disconnect();
+
+			sinon.assert.calledTwice(onErrorStub);
+		});
+
+		it('handles errors throw by tx event listeners', () => {
+			const onEventStub = sandbox.stub().throws('onEvent');
+			const txErrorStub = sandbox.stub().throws('tx onError');
+			const allErrorStub = sandbox.stub().throws('all onError');
+			hub.registerTxEvent('1', onEventStub, txErrorStub, {});
+			hub.registerTxEvent('all', onEventStub, allErrorStub, {});
+
+			hub.disconnect();
+
+			sinon.assert.calledOnce(txErrorStub);
+			sinon.assert.calledOnce(allErrorStub);
+		});
 	});
 
 	describe('#close', () => {
@@ -1528,6 +1556,17 @@ describe('ChannelEventHub', () => {
 			sinon.assert.calledWith(FakeLogger.debug, '_processBlockEvents - calling block listener callback');
 			sinon.assert.calledWith(onEventStub, 'block');
 		});
+
+		it('handles errors thrown from block listeners', () => {
+			const onEventStub = sandbox.stub().throws('onEvent');
+			const onErrorStub = sandbox.stub().throws('onError');
+			hub.registerBlockEvent(onEventStub, onErrorStub, {});
+			hub.registerBlockEvent(onEventStub, onErrorStub, {});
+
+			hub._processBlockEvents('block');
+
+			sinon.assert.calledTwice(onEventStub);
+		});
 	});
 
 	describe('#_processTxEvents', () => {
@@ -1576,6 +1615,26 @@ describe('ChannelEventHub', () => {
 			sinon.assert.calledWith(_checkTransactionIdStub, 1, 'code0', 1);
 			sinon.assert.calledWith(_checkTransactionIdStub, 1, 'code1', 1);
 		});
+
+		it('handles errors thrown from tx event listeners', () => {
+			hub = new ChannelEventHub('channel', 'peer');
+			const fakeTx1 = {txid: '1'};
+			const fakeTx2 = {txid: '2'};
+			const block = {
+				number: 1,
+				filtered_transactions: [fakeTx1, fakeTx2]
+			};
+			const txOnEventStub = sandbox.stub().throws('tx onEvent');
+			const allOnEventStub = sandbox.stub().throws('all onEvent');
+			const onErrorStub = sandbox.stub().throws('onError');
+			hub.registerTxEvent(fakeTx1.txid, txOnEventStub, onErrorStub, {});
+			hub.registerTxEvent('all', allOnEventStub, onErrorStub, {});
+
+			hub._processTxEvents(block);
+
+			sinon.assert.calledOnce(txOnEventStub);
+			sinon.assert.calledTwice(allOnEventStub);
+		});
 	});
 
 	describe('#_checkTransactionId', () => {
@@ -2048,8 +2107,8 @@ describe('EventRegistration', () => {
 
 		it('should set the correct parameters', () => {
 			const reg = new EventRegistration('onEvent', 'onError', null, 'default_unregister', 'default_disconnect');
-			reg.onEvent.should.equal('onEvent');
-			reg.onError.should.equal('onError');
+			reg._onEventFn.should.equal('onEvent');
+			reg._onErrorFn.should.equal('onError');
 			reg.unregister.should.equal('default_unregister');
 			reg.disconnect.should.equal('default_disconnect');
 			reg.unregister_action.should.be.instanceof(Function);