Fix connect ECONNREFUSED error when trying to debug on iOS Sim

When trying to debug on iOS Simulator (via NativeScript Inspector), we often receive `Error: connect ECONNREFUSED 127.0.0.1:18181` error.
There are two different problems. First one is incorrect identifying of the application's PID - we are using `_.trimStart` method totally incorrectly and in case your application identifier has numbers in it, they'll also be replaced in the search PID string. For example in case your app id is `org.nativescript.app10`, and the real PID of the running application is 18129, the current usage of `trimStart` method will give you the PID 8129.
Fix this by applying regular expression and find the correct PID.

The second problem is that there's some delay between opening the NativeScript Inspector and the debugged application on the device. In many cases the first time when we try to connect, we receive the error ECONNREFUSED. However in the previous implementation, we were trying to connect multiple times. Get back the old code and adjust it to work with Promises instead of the old sync execution.

Author: rosen-vladimirov

lib/common

@@ -288,7 +288,7 @@ interface IAndroidToolsInfoData {
 }
 
 interface ISocketProxyFactory extends NodeJS.EventEmitter {
-	createTCPSocketProxy(factory: () => Promise<any>): any;
+	createTCPSocketProxy(factory: () => Promise<any>): Promise<any>;
 	createWebSocketProxy(factory: () => Promise<any>): Promise<any>;
 }
 

lib/declarations.d.ts

@@ -3,6 +3,7 @@ import { CONNECTION_ERROR_EVENT_NAME } from "../../constants";
 import { PacketStream } from "./packet-stream";
 import * as net from "net";
 import * as ws from "ws";
+import * as helpers from "../../common/helpers";
 import temp = require("temp");
 
 export class SocketProxyFactory extends EventEmitter implements ISocketProxyFactory {
@@ -15,6 +16,8 @@ export class SocketProxyFactory extends EventEmitter implements ISocketProxyFact
 	}
 
 	public createTCPSocketProxy(factory: () => Promise<net.Socket>): net.Server {
+		const socketFactory = async (callback: (_socket: net.Socket) => void) => helpers.connectEventually(factory, callback);
+
 		this.$logger.info("\nSetting up proxy...\nPress Ctrl + C to terminate, or disconnect.\n");
 
 		let server = net.createServer({
@@ -31,32 +34,33 @@ export class SocketProxyFactory extends EventEmitter implements ISocketProxyFact
 				}
 			});
 
-			const backendSocket = await factory();
-			this.$logger.info("Backend socket created.");
-
-			backendSocket.on("end", () => {
-				this.$logger.info("Backend socket closed!");
-				if (!(this.$config.debugLivesync && this.$options.watch)) {
-					process.exit(0);
-				}
-			});
+			await socketFactory((backendSocket: net.Socket) => {
+				this.$logger.info("Backend socket created.");
 
-			frontendSocket.on("close", () => {
-				console.log("frontend socket closed");
-				if (!(<any>backendSocket).destroyed) {
-					backendSocket.destroy();
-				}
+				backendSocket.on("end", () => {
+					this.$logger.info("Backend socket closed!");
+					if (!(this.$config.debugLivesync && this.$options.watch)) {
+						process.exit(0);
+					}
+				});
+
+				frontendSocket.on("close", () => {
+					console.log("frontend socket closed");
+					if (!(<any>backendSocket).destroyed) {
+						backendSocket.destroy();
+					}
+				});
+				backendSocket.on("close", () => {
+					console.log("backend socket closed");
+					if (!(<any>frontendSocket).destroyed) {
+						frontendSocket.destroy();
+					}
+				});
+
+				backendSocket.pipe(frontendSocket);
+				frontendSocket.pipe(backendSocket);
+				frontendSocket.resume();
 			});
-			backendSocket.on("close", () => {
-				console.log("backend socket closed");
-				if (!(<any>frontendSocket).destroyed) {
-					frontendSocket.destroy();
-				}
-			});
-
-			backendSocket.pipe(frontendSocket);
-			frontendSocket.pipe(backendSocket);
-			frontendSocket.resume();
 		});
 
 		let socketFileLocation = temp.path({ suffix: ".sock" });

lib/device-sockets/ios/socket-proxy-factory.ts

@@ -103,11 +103,18 @@ class IOSDebugService extends DebugServiceBase implements IPlatformDebugService
 
 		let lineStream = byline(child_process.stdout);
 		this._childProcess = child_process;
+		const pidRegExp = new RegExp(`${debugData.applicationIdentifier}:\\s?(\\d+)`);
 
 		lineStream.on('data', (line: NodeBuffer) => {
 			let lineText = line.toString();
 			if (lineText && _.startsWith(lineText, debugData.applicationIdentifier)) {
-				let pid = _.trimStart(lineText, debugData.applicationIdentifier + ": ");
+				const pidMatch = lineText.match(pidRegExp);
+
+				if (!pidMatch) {
+					this.$logger.trace(`Line ${lineText} does not contain the searched pattern: ${pidRegExp}.`);
+				}
+
+				const pid = pidMatch[1];
 				this._lldbProcess = this.$childProcess.spawn("lldb", ["-p", pid]);
 				if (log4js.levels.TRACE.isGreaterThanOrEqualTo(this.$logger.getLevel())) {
 					this._lldbProcess.stdout.pipe(process.stdout);