Expose getLiveSyncDeviceDescriptors method

Add new public method `getLiveSyncDeviceDescriptors` to `liveSyncService` - its purpose is to get information for current LiveSync operation.

Author: rosen-vladimirov

PublicAPI.md

@@ -623,6 +623,29 @@ tns.liveSyncService.stopLiveSync(projectDir, deviceIdentifiers)
 	});
 ```
 
+### getLiveSyncDeviceDescriptors
+Gives information for currently running LiveSync operation and parameters used to start it on each device.
+
+* Definition
+```TypeScript
+/**
+ * Returns the device information for current LiveSync operation of specified project.
+ * In case LiveSync has been started on many devices, but stopped for some of them at a later point,
+ * calling the method after that will return information only for devices for which LiveSync operation is in progress.
+ * @param {string} projectDir The path to project for which the LiveSync operation is executed
+ * @returns {ILiveSyncDeviceInfo[]} Array of elements describing parameters used to start LiveSync on each device.
+*/
+getLiveSyncDeviceDescriptors(projectDir: string): ILiveSyncDeviceInfo[];
+```
+
+* Usage
+```JavaScript
+const projectDir = "myProjectDir";
+const deviceIdentifiers = [ "4df18f307d8a8f1b", "12318af23ebc0e25" ];
+const currentlyRunningDescriptors = tns.liveSyncService.getLiveSyncDeviceDescriptors(projectDir);
+console.log(`LiveSync for ${projectDir} is currently running on the following devices: ${currentlyRunningDescriptors.map(descriptor => descriptor.identifier)}`);
+```
+
 ### Events
 `liveSyncService` raises several events in order to provide information for current state of the operation.
 * liveSyncStarted - raised whenever CLI starts a LiveSync operation for specific device. When `liveSync` method is called, the initial LiveSync operation will emit `liveSyncStarted` for each specified device. After that the event will be emitted only in case when liveSync method is called again with different device instances. The event is raised with the following data:

lib/definitions/livesync.d.ts

@@ -185,6 +185,15 @@ interface ILiveSyncService {
 	 * @returns {Promise<void>}
 	 */
 	stopLiveSync(projectDir: string, deviceIdentifiers?: string[], stopOptions?: { shouldAwaitAllActions: boolean }): Promise<void>;
+
+	/**
+	 * Returns the device information for current LiveSync operation of specified project.
+	 * In case LiveSync has been started on many devices, but stopped for some of them at a later point,
+	 * calling the method after that will return information only for devices for which LiveSync operation is in progress.
+	 * @param {string} projectDir The path to project for which the LiveSync operation is executed
+	 * @returns {ILiveSyncDeviceInfo[]} Array of elements describing parameters used to start LiveSync on each device.
+	 */
+	getLiveSyncDeviceDescriptors(projectDir: string): ILiveSyncDeviceInfo[];
 }
 
 /**

lib/services/livesync/livesync-service.ts

@@ -50,7 +50,7 @@ export class LiveSyncService extends EventEmitter implements ILiveSyncService {
 
 			const deviceIdentifiersToRemove = deviceIdentifiers || _.map(liveSyncProcessInfo.deviceDescriptors, d => d.identifier);
 
-			const removedDeviceIdentifiers = _.remove(liveSyncProcessInfo.deviceDescriptors, descriptor => _.indexOf(deviceIdentifiersToRemove, descriptor.identifier) !== -1)
+			const removedDeviceIdentifiers = _.remove(liveSyncProcessInfo.deviceDescriptors, descriptor => _.includes(deviceIdentifiersToRemove, descriptor.identifier))
 				.map(descriptor => descriptor.identifier);
 
 			// In case deviceIdentifiers are not passed, we should stop the whole LiveSync.
@@ -90,6 +90,12 @@ export class LiveSyncService extends EventEmitter implements ILiveSyncService {
 		}
 	}
 
+	public getLiveSyncDeviceDescriptors(projectDir: string): ILiveSyncDeviceInfo[] {
+		const liveSyncProcessesInfo = this.liveSyncProcessesInfo[projectDir] || <ILiveSyncProcessInfo>{};
+		const currentDescriptors = liveSyncProcessesInfo.deviceDescriptors;
+		return currentDescriptors || [];
+	}
+
 	protected async refreshApplication(projectData: IProjectData, liveSyncResultInfo: ILiveSyncResultInfo): Promise<void> {
 		const platformLiveSyncService = this.getLiveSyncService(liveSyncResultInfo.deviceAppData.platform);
 		try {
@@ -124,7 +130,8 @@ export class LiveSyncService extends EventEmitter implements ILiveSyncService {
 		const isAlreadyLiveSyncing = this.liveSyncProcessesInfo[projectData.projectDir] && !this.liveSyncProcessesInfo[projectData.projectDir].isStopped;
 
 		// Prevent cases where liveSync is called consecutive times with the same device, for example [ A, B, C ] and then [ A, B, D ] - we want to execute initialSync only for D.
-		const deviceDescriptorsForInitialSync = isAlreadyLiveSyncing ? _.differenceBy(deviceDescriptors, this.liveSyncProcessesInfo[projectData.projectDir].deviceDescriptors, deviceDescriptorPrimaryKey) : deviceDescriptors;
+		const currentlyRunningDeviceDescriptors = this.getLiveSyncDeviceDescriptors(projectData.projectDir);
+		const deviceDescriptorsForInitialSync = isAlreadyLiveSyncing ? _.differenceBy(deviceDescriptors, currentlyRunningDeviceDescriptors, deviceDescriptorPrimaryKey) : deviceDescriptors;
 		this.setLiveSyncProcessInfo(liveSyncData.projectDir, deviceDescriptors);
 
 		await this.initialSync(projectData, deviceDescriptorsForInitialSync, liveSyncData);
@@ -143,7 +150,7 @@ export class LiveSyncService extends EventEmitter implements ILiveSyncService {
 		this.liveSyncProcessesInfo[projectDir].currentSyncAction = this.liveSyncProcessesInfo[projectDir].actionsChain;
 		this.liveSyncProcessesInfo[projectDir].isStopped = false;
 
-		const currentDeviceDescriptors = this.liveSyncProcessesInfo[projectDir].deviceDescriptors || [];
+		const currentDeviceDescriptors = this.getLiveSyncDeviceDescriptors(projectDir);
 		this.liveSyncProcessesInfo[projectDir].deviceDescriptors = _.uniqBy(currentDeviceDescriptors.concat(deviceDescriptors), deviceDescriptorPrimaryKey);
 	}
 

test/stubs.ts

@@ -500,6 +500,10 @@ export class LiveSyncServiceStub implements ILiveSyncService {
 	public async stopLiveSync(projectDir: string): Promise<void> {
 		return;
 	}
+
+	public getLiveSyncDeviceDescriptors(projectDir: string): ILiveSyncDeviceInfo[] {
+		return [];
+	}
 }
 
 export class AndroidToolsInfoStub implements IAndroidToolsInfo {