Adding functionality to subscribe command that exits after receving s…

…o many events or after receiving an event with matching data. Tests are needed.

src/cli/subscribe.js

@@ -8,6 +8,13 @@ module.exports = ({ commandProcessor, root }) => {
 			},
 			'device': {
 				describe: 'Listen to events from this device only'
+			},
+			'until': {
+				describe: 'Listen until we see an event exactly matching this data'
+			},
+			'count': {
+				number: true,
+				describe: 'Listen until we see this many events'
 			}
 		},
 		handler: (args) => {
@@ -18,7 +25,9 @@ module.exports = ({ commandProcessor, root }) => {
 			'$0 $command': 'Subscribe to all event published by my devices',
 			'$0 $command update': 'Subscribe to events starting with update from my devices',
 			'$0 $command --device x': 'Subscribe to all events published by device x',
-			'$0 $command --all': 'Subscribe to public events and all events published by my devices'
+			'$0 $command --all': 'Subscribe to public events and all events published by my devices',
+			'$0 $command --until x': 'Subscribe to all events and exit when an event has data matching x',
+			'$0 $command --count x': 'Subscribe to all events and exit after seeing x events'
 		}
 	});
 };

src/cmd/subscribe.js

@@ -3,7 +3,7 @@ const ApiClient = require('../lib/api-client');
 
 
 module.exports = class SubscribeCommand {
-	startListening(event, { device, all }) {
+	startListening(event, { device, all, until, max }) {
 		const api = new ApiClient();
 		api.ensureToken();
 
@@ -35,6 +35,16 @@ module.exports = class SubscribeCommand {
 			console.log('Subscribing to ' + eventLabel + ' from ' + deviceId + "'s stream");
 		}
 
+		if (until) {
+			console.log(`This command will exit after receiving event data matching: '${until}'`);
+		}
+
+		let eventCount = 0;
+		if (max) {
+			max = Math.abs(max);
+			console.log(`This command will exit after receiving ${max} event(s)...`);
+		}
+
 		let chunks = [];
 		function appendToQueue(arr) {
 			for (let i = 0; i < arr.length; i++) {
@@ -64,6 +74,19 @@ module.exports = class SubscribeCommand {
 			}
 
 			console.log(JSON.stringify(obj));
+
+			if (until && until === obj.data) {
+				console.log('Matching event received. Exiting...');
+				process.exit(1); // One matching event
+			}
+
+			if (max) {
+				eventCount = eventCount + 1;
+				if (eventCount === max) {
+					console.log(`${eventCount} event(s) received. Exiting...`);
+					process.exit(eventCount); // Number of events we received
+				}
+			}
 		}
 
 		return api.getEventStream(eventName, deviceId, (event) => {