fix(serve): assign all ports dynamically (#727)

Up to now only the logger port was dynamically increased if another app
is running already. This meant that manually specifying port arguments
for server and live reload was needed when directly using the
`ionic-app-scripts server` command. The `ionic` CLI command does
already take care of this.

This patch ensures all the ports are chosen dynamically, so it's now
possible to run two applications without any manual intervention.

src/serve.ts

@@ -9,7 +9,7 @@ import { createNotificationServer } from './dev-server/notification-server';
 import { createHttpServer } from './dev-server/http-server';
 import { createLiveReloadServer } from './dev-server/live-reload';
 import { ServeConfig, IONIC_LAB_URL } from './dev-server/serve-config';
-import { findClosestOpenPort } from './util/network';
+import { findClosestOpenPorts } from './util/network';
 
 const DEV_LOGGER_DEFAULT_PORT = 53703;
 const LIVE_RELOAD_DEFAULT_PORT = 35729;
@@ -20,18 +20,19 @@ export function serve(context: BuildContext) {
   setContext(context);
 
   let config: ServeConfig;
-  const notificationPort = getNotificationPort(context);
   const host = getHttpServerHost(context);
+  const notificationPort = getNotificationPort(context);
+  const liveReloadServerPort = getLiveReloadServerPort(context);
+  const hostPort = getHttpServerPort(context);
 
-  return findClosestOpenPort(host, notificationPort)
-    .then((notificationPortFound) => {
-      const hostPort = getHttpServerPort(context);
+  return findClosestOpenPorts(host, [notificationPort, liveReloadServerPort, hostPort])
+    .then(([notificationPortFound, liveReloadServerPortFound, hostPortFound]) => {
       const hostLocation = (host === '0.0.0.0') ? 'localhost' : host;
 
       config = {
-        httpPort: hostPort,
+        httpPort: hostPortFound,
         host: host,
-        hostBaseUrl: `http://${hostLocation}:${hostPort}`,
+        hostBaseUrl: `http://${hostLocation}:${hostPortFound}`,
         rootDir: context.rootDir,
         wwwDir: context.wwwDir,
         buildDir: context.buildDir,
@@ -40,7 +41,7 @@ export function serve(context: BuildContext) {
         launchLab: launchLab(context),
         browserToLaunch: browserToLaunch(context),
         useLiveReload: useLiveReload(context),
-        liveReloadPort: getLiveReloadServerPort(context),
+        liveReloadPort: liveReloadServerPortFound,
         notificationPort: notificationPortFound,
         useServerLogs: useServerLogs(context),
         useProxy: useProxy(context),

src/util/network.ts

@@ -1,5 +1,10 @@
 import * as net from 'net';
 
+export function findClosestOpenPorts(host: string, ports: number[]): Promise<number[]> {
+  const promises = ports.map(port => findClosestOpenPort(host, port));
+  return Promise.all(promises);
+}
+
 export function findClosestOpenPort(host: string, port: number): Promise<number> {
   function t(portToCheck: number): Promise<number> {
     return isPortTaken(host, portToCheck).then(isTaken => {