chore: convert some server files into TypeScript (#757)

packages/cli/package.json

@@ -30,6 +30,8 @@
     "@react-native-community/cli-types": "^3.0.0-alpha.2",
     "@types/mkdirp": "^0.5.2",
     "@types/semver": "^6.0.2",
+    "@types/ws": "^6.0.3",
+    "@types/node-notifier": "^5.4.0",
     "chalk": "^2.4.2",
     "command-exists": "^1.2.8",
     "commander": "^2.19.0",

packages/cli/src/commands/server/copyToClipBoard.js → packages/cli/src/commands/server/copyToClipBoard.ts

@@ -18,7 +18,7 @@ fs.chmodSync(xsel, '0755');
 /**
  * Copy the content to host system clipboard.
  */
-function copyToClipBoard(content) {
+function copyToClipBoard(content: string) {
   switch (process.platform) {
     case 'darwin': {
       const child = spawn('pbcopy', []);

packages/cli/src/commands/server/launchDebugger.js → packages/cli/src/commands/server/launchDebugger.ts

@@ -5,7 +5,6 @@
  * LICENSE file in the root directory of this source tree.
  *
  * @format
- * @flow
  */
 
 import open from 'open';
@@ -14,7 +13,7 @@ import {logger} from '@react-native-community/cli-tools';
 import launchDefaultBrowser from './launchDefaultBrowser';
 import chalk from 'chalk';
 
-function commandExistsUnixSync(commandName) {
+function commandExistsUnixSync(commandName: string) {
   try {
     const stdout = execSync(
       `command -v ${commandName} 2>/dev/null` +

packages/cli/src/commands/server/launchDefaultBrowser.js → packages/cli/src/commands/server/launchDefaultBrowser.ts

@@ -5,18 +5,19 @@
  * LICENSE file in the root directory of this source tree.
  *
  * @format
- * @flow
  */
 
 import open from 'open';
 import {logger} from '@react-native-community/cli-tools';
 
-function launchDefaultBrowser(url: string) {
-  open(url, err => {
+async function launchDefaultBrowser(url: string) {
+  try {
+    await open(url);
+  } catch (err) {
     if (err) {
       logger.error('Browser exited with error:', err);
     }
-  });
+  }
 }
 
 export default launchDefaultBrowser;

packages/cli/src/commands/server/launchEditor.js → packages/cli/src/commands/server/launchEditor.ts

@@ -10,11 +10,12 @@
 import chalk from 'chalk';
 import fs from 'fs';
 import path from 'path';
-import {execSync, spawn} from 'child_process';
+import {execSync, spawn, ChildProcess} from 'child_process';
+// @ts-ignore @types not installed
 import shellQuote from 'shell-quote';
 import {logger} from '@react-native-community/cli-tools';
 
-function isTerminalEditor(editor) {
+function isTerminalEditor(editor: string) {
   switch (editor) {
     case 'vim':
     case 'emacs':
@@ -28,7 +29,7 @@ function isTerminalEditor(editor) {
 // Map from full process name to binary that starts the process
 // We can't just re-use full process name, because it will spawn a new instance
 // of the app every time
-const COMMON_EDITORS = {
+const COMMON_EDITORS: Record<string, string> = {
   '/Applications/Atom.app/Contents/MacOS/Atom': 'atom',
   '/Applications/Atom Beta.app/Contents/MacOS/Atom Beta':
     '/Applications/Atom Beta.app/Contents/MacOS/Atom Beta',
@@ -46,14 +47,19 @@ const COMMON_EDITORS = {
 // alphanumeric characters, periods, dashes, slashes, and underscores.
 const WINDOWS_FILE_NAME_WHITELIST = /^(?:[\x2D-9A-Z\\_a-z\xAA\xB5\xBA\xC0-\xD6\xD8-\xF6\xF8-\u02C1\u02C6-\u02D1\u02E0-\u02E4\u02EC\u02EE\u0370-\u0374\u0376\u0377\u037A-\u037D\u037F\u0386\u0388-\u038A\u038C\u038E-\u03A1\u03A3-\u03F5\u03F7-\u0481\u048A-\u052F\u0531-\u0556\u0559\u0560-\u0588\u05D0-\u05EA\u05EF-\u05F2\u0620-\u064A\u066E\u066F\u0671-\u06D3\u06D5\u06E5\u06E6\u06EE\u06EF\u06FA-\u06FC\u06FF\u0710\u0712-\u072F\u074D-\u07A5\u07B1\u07CA-\u07EA\u07F4\u07F5\u07FA\u0800-\u0815\u081A\u0824\u0828\u0840-\u0858\u0860-\u086A\u08A0-\u08B4\u08B6-\u08BD\u0904-\u0939\u093D\u0950\u0958-\u0961\u0971-\u0980\u0985-\u098C\u098F\u0990\u0993-\u09A8\u09AA-\u09B0\u09B2\u09B6-\u09B9\u09BD\u09CE\u09DC\u09DD\u09DF-\u09E1\u09F0\u09F1\u09FC\u0A05-\u0A0A\u0A0F\u0A10\u0A13-\u0A28\u0A2A-\u0A30\u0A32\u0A33\u0A35\u0A36\u0A38\u0A39\u0A59-\u0A5C\u0A5E\u0A72-\u0A74\u0A85-\u0A8D\u0A8F-\u0A91\u0A93-\u0AA8\u0AAA-\u0AB0\u0AB2\u0AB3\u0AB5-\u0AB9\u0ABD\u0AD0\u0AE0\u0AE1\u0AF9\u0B05-\u0B0C\u0B0F\u0B10\u0B13-\u0B28\u0B2A-\u0B30\u0B32\u0B33\u0B35-\u0B39\u0B3D\u0B5C\u0B5D\u0B5F-\u0B61\u0B71\u0B83\u0B85-\u0B8A\u0B8E-\u0B90\u0B92-\u0B95\u0B99\u0B9A\u0B9C\u0B9E\u0B9F\u0BA3\u0BA4\u0BA8-\u0BAA\u0BAE-\u0BB9\u0BD0\u0C05-\u0C0C\u0C0E-\u0C10\u0C12-\u0C28\u0C2A-\u0C39\u0C3D\u0C58-\u0C5A\u0C60\u0C61\u0C80\u0C85-\u0C8C\u0C8E-\u0C90\u0C92-\u0CA8\u0CAA-\u0CB3\u0CB5-\u0CB9\u0CBD\u0CDE\u0CE0\u0CE1\u0CF1\u0CF2\u0D05-\u0D0C\u0D0E-\u0D10\u0D12-\u0D3A\u0D3D\u0D4E\u0D54-\u0D56\u0D5F-\u0D61\u0D7A-\u0D7F\u0D85-\u0D96\u0D9A-\u0DB1\u0DB3-\u0DBB\u0DBD\u0DC0-\u0DC6\u0E01-\u0E30\u0E32\u0E33\u0E40-\u0E46\u0E81\u0E82\u0E84\u0E87\u0E88\u0E8A\u0E8D\u0E94-\u0E97\u0E99-\u0E9F\u0EA1-\u0EA3\u0EA5\u0EA7\u0EAA\u0EAB\u0EAD-\u0EB0\u0EB2\u0EB3\u0EBD\u0EC0-\u0EC4\u0EC6\u0EDC-\u0EDF\u0F00\u0F40-\u0F47\u0F49-\u0F6C\u0F88-\u0F8C\u1000-\u102A\u103F\u1050-\u1055\u105A-\u105D\u1061\u1065\u1066\u106E-\u1070\u1075-\u1081\u108E\u10A0-\u10C5\u10C7\u10CD\u10D0-\u10FA\u10FC-\u1248\u124A-\u124D\u1250-\u1256\u1258\u125A-\u125D\u1260-\u1288\u128A-\u128D\u1290-\u12B0\u12B2-\u12B5\u12B8-\u12BE\u12C0\u12C2-\u12C5\u12C8-\u12D6\u12D8-\u1310\u1312-\u1315\u1318-\u135A\u1380-\u138F\u13A0-\u13F5\u13F8-\u13FD\u1401-\u166C\u166F-\u167F\u1681-\u169A\u16A0-\u16EA\u16F1-\u16F8\u1700-\u170C\u170E-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176C\u176E-\u1770\u1780-\u17B3\u17D7\u17DC\u1820-\u1878\u1880-\u1884\u1887-\u18A8\u18AA\u18B0-\u18F5\u1900-\u191E\u1950-\u196D\u1970-\u1974\u1980-\u19AB\u19B0-\u19C9\u1A00-\u1A16\u1A20-\u1A54\u1AA7\u1B05-\u1B33\u1B45-\u1B4B\u1B83-\u1BA0\u1BAE\u1BAF\u1BBA-\u1BE5\u1C00-\u1C23\u1C4D-\u1C4F\u1C5A-\u1C7D\u1C80-\u1C88\u1C90-\u1CBA\u1CBD-\u1CBF\u1CE9-\u1CEC\u1CEE-\u1CF1\u1CF5\u1CF6\u1D00-\u1DBF\u1E00-\u1F15\u1F18-\u1F1D\u1F20-\u1F45\u1F48-\u1F4D\u1F50-\u1F57\u1F59\u1F5B\u1F5D\u1F5F-\u1F7D\u1F80-\u1FB4\u1FB6-\u1FBC\u1FBE\u1FC2-\u1FC4\u1FC6-\u1FCC\u1FD0-\u1FD3\u1FD6-\u1FDB\u1FE0-\u1FEC\u1FF2-\u1FF4\u1FF6-\u1FFC\u2071\u207F\u2090-\u209C\u2102\u2107\u210A-\u2113\u2115\u2119-\u211D\u2124\u2126\u2128\u212A-\u212D\u212F-\u2139\u213C-\u213F\u2145-\u2149\u214E\u2183\u2184\u2C00-\u2C2E\u2C30-\u2C5E\u2C60-\u2CE4\u2CEB-\u2CEE\u2CF2\u2CF3\u2D00-\u2D25\u2D27\u2D2D\u2D30-\u2D67\u2D6F\u2D80-\u2D96\u2DA0-\u2DA6\u2DA8-\u2DAE\u2DB0-\u2DB6\u2DB8-\u2DBE\u2DC0-\u2DC6\u2DC8-\u2DCE\u2DD0-\u2DD6\u2DD8-\u2DDE\u2E2F\u3005\u3006\u3031-\u3035\u303B\u303C\u3041-\u3096\u309D-\u309F\u30A1-\u30FA\u30FC-\u30FF\u3105-\u312F\u3131-\u318E\u31A0-\u31BA\u31F0-\u31FF\u3400-\u4DB5\u4E00-\u9FEF\uA000-\uA48C\uA4D0-\uA4FD\uA500-\uA60C\uA610-\uA61F\uA62A\uA62B\uA640-\uA66E\uA67F-\uA69D\uA6A0-\uA6E5\uA717-\uA71F\uA722-\uA788\uA78B-\uA7B9\uA7F7-\uA801\uA803-\uA805\uA807-\uA80A\uA80C-\uA822\uA840-\uA873\uA882-\uA8B3\uA8F2-\uA8F7\uA8FB\uA8FD\uA8FE\uA90A-\uA925\uA930-\uA946\uA960-\uA97C\uA984-\uA9B2\uA9CF\uA9E0-\uA9E4\uA9E6-\uA9EF\uA9FA-\uA9FE\uAA00-\uAA28\uAA40-\uAA42\uAA44-\uAA4B\uAA60-\uAA76\uAA7A\uAA7E-\uAAAF\uAAB1\uAAB5\uAAB6\uAAB9-\uAABD\uAAC0\uAAC2\uAADB-\uAADD\uAAE0-\uAAEA\uAAF2-\uAAF4\uAB01-\uAB06\uAB09-\uAB0E\uAB11-\uAB16\uAB20-\uAB26\uAB28-\uAB2E\uAB30-\uAB5A\uAB5C-\uAB65\uAB70-\uABE2\uAC00-\uD7A3\uD7B0-\uD7C6\uD7CB-\uD7FB\uF900-\uFA6D\uFA70-\uFAD9\uFB00-\uFB06\uFB13-\uFB17\uFB1D\uFB1F-\uFB28\uFB2A-\uFB36\uFB38-\uFB3C\uFB3E\uFB40\uFB41\uFB43\uFB44\uFB46-\uFBB1\uFBD3-\uFD3D\uFD50-\uFD8F\uFD92-\uFDC7\uFDF0-\uFDFB\uFE70-\uFE74\uFE76-\uFEFC\uFF21-\uFF3A\uFF41-\uFF5A\uFF66-\uFFBE\uFFC2-\uFFC7\uFFCA-\uFFCF\uFFD2-\uFFD7\uFFDA-\uFFDC]|\uD800[\uDC00-\uDC0B\uDC0D-\uDC26\uDC28-\uDC3A\uDC3C\uDC3D\uDC3F-\uDC4D\uDC50-\uDC5D\uDC80-\uDCFA\uDE80-\uDE9C\uDEA0-\uDED0\uDF00-\uDF1F\uDF2D-\uDF40\uDF42-\uDF49\uDF50-\uDF75\uDF80-\uDF9D\uDFA0-\uDFC3\uDFC8-\uDFCF]|\uD801[\uDC00-\uDC9D\uDCB0-\uDCD3\uDCD8-\uDCFB\uDD00-\uDD27\uDD30-\uDD63\uDE00-\uDF36\uDF40-\uDF55\uDF60-\uDF67]|\uD802[\uDC00-\uDC05\uDC08\uDC0A-\uDC35\uDC37\uDC38\uDC3C\uDC3F-\uDC55\uDC60-\uDC76\uDC80-\uDC9E\uDCE0-\uDCF2\uDCF4\uDCF5\uDD00-\uDD15\uDD20-\uDD39\uDD80-\uDDB7\uDDBE\uDDBF\uDE00\uDE10-\uDE13\uDE15-\uDE17\uDE19-\uDE35\uDE60-\uDE7C\uDE80-\uDE9C\uDEC0-\uDEC7\uDEC9-\uDEE4\uDF00-\uDF35\uDF40-\uDF55\uDF60-\uDF72\uDF80-\uDF91]|\uD803[\uDC00-\uDC48\uDC80-\uDCB2\uDCC0-\uDCF2\uDD00-\uDD23\uDF00-\uDF1C\uDF27\uDF30-\uDF45]|\uD804[\uDC03-\uDC37\uDC83-\uDCAF\uDCD0-\uDCE8\uDD03-\uDD26\uDD44\uDD50-\uDD72\uDD76\uDD83-\uDDB2\uDDC1-\uDDC4\uDDDA\uDDDC\uDE00-\uDE11\uDE13-\uDE2B\uDE80-\uDE86\uDE88\uDE8A-\uDE8D\uDE8F-\uDE9D\uDE9F-\uDEA8\uDEB0-\uDEDE\uDF05-\uDF0C\uDF0F\uDF10\uDF13-\uDF28\uDF2A-\uDF30\uDF32\uDF33\uDF35-\uDF39\uDF3D\uDF50\uDF5D-\uDF61]|\uD805[\uDC00-\uDC34\uDC47-\uDC4A\uDC80-\uDCAF\uDCC4\uDCC5\uDCC7\uDD80-\uDDAE\uDDD8-\uDDDB\uDE00-\uDE2F\uDE44\uDE80-\uDEAA\uDF00-\uDF1A]|\uD806[\uDC00-\uDC2B\uDCA0-\uDCDF\uDCFF\uDE00\uDE0B-\uDE32\uDE3A\uDE50\uDE5C-\uDE83\uDE86-\uDE89\uDE9D\uDEC0-\uDEF8]|\uD807[\uDC00-\uDC08\uDC0A-\uDC2E\uDC40\uDC72-\uDC8F\uDD00-\uDD06\uDD08\uDD09\uDD0B-\uDD30\uDD46\uDD60-\uDD65\uDD67\uDD68\uDD6A-\uDD89\uDD98\uDEE0-\uDEF2]|\uD808[\uDC00-\uDF99]|\uD809[\uDC80-\uDD43]|[\uD80C\uD81C-\uD820\uD840-\uD868\uD86A-\uD86C\uD86F-\uD872\uD874-\uD879][\uDC00-\uDFFF]|\uD80D[\uDC00-\uDC2E]|\uD811[\uDC00-\uDE46]|\uD81A[\uDC00-\uDE38\uDE40-\uDE5E\uDED0-\uDEED\uDF00-\uDF2F\uDF40-\uDF43\uDF63-\uDF77\uDF7D-\uDF8F]|\uD81B[\uDE40-\uDE7F\uDF00-\uDF44\uDF50\uDF93-\uDF9F\uDFE0\uDFE1]|\uD821[\uDC00-\uDFF1]|\uD822[\uDC00-\uDEF2]|\uD82C[\uDC00-\uDD1E\uDD70-\uDEFB]|\uD82F[\uDC00-\uDC6A\uDC70-\uDC7C\uDC80-\uDC88\uDC90-\uDC99]|\uD835[\uDC00-\uDC54\uDC56-\uDC9C\uDC9E\uDC9F\uDCA2\uDCA5\uDCA6\uDCA9-\uDCAC\uDCAE-\uDCB9\uDCBB\uDCBD-\uDCC3\uDCC5-\uDD05\uDD07-\uDD0A\uDD0D-\uDD14\uDD16-\uDD1C\uDD1E-\uDD39\uDD3B-\uDD3E\uDD40-\uDD44\uDD46\uDD4A-\uDD50\uDD52-\uDEA5\uDEA8-\uDEC0\uDEC2-\uDEDA\uDEDC-\uDEFA\uDEFC-\uDF14\uDF16-\uDF34\uDF36-\uDF4E\uDF50-\uDF6E\uDF70-\uDF88\uDF8A-\uDFA8\uDFAA-\uDFC2\uDFC4-\uDFCB]|\uD83A[\uDC00-\uDCC4\uDD00-\uDD43]|\uD83B[\uDE00-\uDE03\uDE05-\uDE1F\uDE21\uDE22\uDE24\uDE27\uDE29-\uDE32\uDE34-\uDE37\uDE39\uDE3B\uDE42\uDE47\uDE49\uDE4B\uDE4D-\uDE4F\uDE51\uDE52\uDE54\uDE57\uDE59\uDE5B\uDE5D\uDE5F\uDE61\uDE62\uDE64\uDE67-\uDE6A\uDE6C-\uDE72\uDE74-\uDE77\uDE79-\uDE7C\uDE7E\uDE80-\uDE89\uDE8B-\uDE9B\uDEA1-\uDEA3\uDEA5-\uDEA9\uDEAB-\uDEBB]|\uD869[\uDC00-\uDED6\uDF00-\uDFFF]|\uD86D[\uDC00-\uDF34\uDF40-\uDFFF]|\uD86E[\uDC00-\uDC1D\uDC20-\uDFFF]|\uD873[\uDC00-\uDEA1\uDEB0-\uDFFF]|\uD87A[\uDC00-\uDFE0]|\uD87E[\uDC00-\uDE1D])+$/;
 
-function addWorkspaceToArgumentsIfExists(args, workspace) {
+function addWorkspaceToArgumentsIfExists(args: string[], workspace: string) {
   if (workspace) {
     args.unshift(workspace);
   }
   return args;
 }
 
-function getArgumentsForLineNumber(editor, fileName, lineNumber, workspace) {
+function getArgumentsForLineNumber(
+  editor: string,
+  fileName: string,
+  lineNumber: number,
+  workspace: any,
+) {
   switch (path.basename(editor)) {
     case 'vim':
     case 'mvim':
@@ -124,7 +130,7 @@ function guessEditor() {
   return [null];
 }
 
-function printInstructions(title) {
+function printInstructions(title: string) {
   logger.info(
     [
       '',
@@ -140,23 +146,27 @@ function printInstructions(title) {
   );
 }
 
-function transformToAbsolutePathIfNeeded(pathName) {
+function transformToAbsolutePathIfNeeded(pathName: string) {
   if (!path.isAbsolute(pathName)) {
     return path.resolve(process.cwd(), pathName);
   }
   return pathName;
 }
 
-function findRootForFile(projectRoots, fileName) {
+function findRootForFile(projectRoots: string[], fileName: string) {
   const absoluteFileName = transformToAbsolutePathIfNeeded(fileName);
   return projectRoots.find(root => {
     const absoluteRoot = transformToAbsolutePathIfNeeded(root);
     return absoluteFileName.startsWith(absoluteRoot + path.sep);
   });
 }
 
-let _childProcess = null;
-function launchEditor(fileName, lineNumber, projectRoots) {
+let _childProcess: ChildProcess | null = null;
+function launchEditor(
+  fileName: string,
+  lineNumber: number,
+  projectRoots: string[],
+) {
   if (!fs.existsSync(fileName)) {
     return;
   }

packages/cli/src/commands/server/messageSocket.js → packages/cli/src/commands/server/messageSocket.ts

@@ -9,10 +9,27 @@ import url from 'url';
 import {Server as WebSocketServer} from 'ws';
 import notifier from 'node-notifier';
 import {logger} from '@react-native-community/cli-tools';
+import {Server as HttpServer} from 'http';
+import {Server as HttpsServer} from 'https';
 
 const PROTOCOL_VERSION = 2;
 
-function parseMessage(data, binary) {
+type IdObject = {
+  requestId: string;
+  clientId: string;
+};
+
+type Message = {
+  version?: string;
+  id?: IdObject;
+  method?: string;
+  target: string;
+  result?: any;
+  error?: Error;
+  params?: Record<string, any>;
+};
+
+function parseMessage(data: string, binary: any) {
   if (binary) {
     logger.error('Expected text message, got binary!');
     return undefined;
@@ -31,21 +48,21 @@ function parseMessage(data, binary) {
   return undefined;
 }
 
-function isBroadcast(message) {
+function isBroadcast(message: Message) {
   return (
     typeof message.method === 'string' &&
     message.id === undefined &&
     message.target === undefined
   );
 }
 
-function isRequest(message) {
+function isRequest(message: Message) {
   return (
     typeof message.method === 'string' && typeof message.target === 'string'
   );
 }
 
-function isResponse(message) {
+function isResponse(message: Message) {
   return (
     typeof message.id === 'object' &&
     typeof message.id.requestId !== 'undefined' &&
@@ -54,15 +71,16 @@ function isResponse(message) {
   );
 }
 
-function attachToServer(server, path) {
+type Server = HttpServer | HttpsServer;
+function attachToServer(server: Server, path: string) {
   const wss = new WebSocketServer({
     server,
     path,
   });
   const clients = new Map();
   let nextClientId = 0;
 
-  function getClientWs(clientId) {
+  function getClientWs(clientId: string) {
     const clientWs = clients.get(clientId);
     if (clientWs === undefined) {
       throw new Error(
@@ -72,7 +90,10 @@ function attachToServer(server, path) {
     return clientWs;
   }
 
-  function handleSendBroadcast(broadcasterId, message) {
+  function handleSendBroadcast(
+    broadcasterId: string | null,
+    message: Partial<Message>,
+  ) {
     const forwarded = {
       version: PROTOCOL_VERSION,
       method: message.method,
@@ -104,7 +125,7 @@ function attachToServer(server, path) {
   wss.on('connection', clientWs => {
     const clientId = `client#${nextClientId++}`;
 
-    function handleCaughtError(message, error) {
+    function handleCaughtError(message: Message, error: Error) {
       const errorMessage = {
         id: message.id,
         method: message.method,
@@ -138,7 +159,7 @@ function attachToServer(server, path) {
       }
     }
 
-    function handleServerRequest(message) {
+    function handleServerRequest(message: Message) {
       let result = null;
       switch (message.method) {
         case 'getid':
@@ -165,7 +186,7 @@ function attachToServer(server, path) {
       );
     }
 
-    function forwardRequest(message) {
+    function forwardRequest(message: Message) {
       getClientWs(message.target).send(
         JSON.stringify({
           version: PROTOCOL_VERSION,
@@ -179,7 +200,10 @@ function attachToServer(server, path) {
       );
     }
 
-    function forwardResponse(message) {
+    function forwardResponse(message: Message) {
+      if (!message.id) {
+        return;
+      }
       getClientWs(message.id.clientId).send(
         JSON.stringify({
           version: PROTOCOL_VERSION,
@@ -192,12 +216,13 @@ function attachToServer(server, path) {
 
     clients.set(clientId, clientWs);
     const onCloseHandler = () => {
+      // @ts-ignore
       clientWs.onmessage = null;
       clients.delete(clientId);
     };
     clientWs.onclose = onCloseHandler;
     clientWs.onerror = onCloseHandler;
-    clientWs.onmessage = event => {
+    clientWs.onmessage = (event: any) => {
       const message = parseMessage(event.data, event.binary);
       if (message === undefined) {
         logger.error('Received message not matching protocol');
@@ -225,7 +250,7 @@ function attachToServer(server, path) {
   });
 
   return {
-    broadcast: (method, params) => {
+    broadcast: (method: string, params: Record<string, any>) => {
       handleSendBroadcast(null, {method, params});
     },
   };

packages/cli/src/commands/server/runServer.js

@@ -13,7 +13,9 @@ import morgan from 'morgan';
 import path from 'path';
 import {logger} from '@react-native-community/cli-tools';
 import type {ConfigT} from 'types';
+// $FlowFixMe - converted to TS
 import messageSocket from './messageSocket';
+// $FlowFixMe - converted to TS
 import webSocketProxy from './webSocketProxy';
 import MiddlewareManager from './middleware/MiddlewareManager';
 // $FlowFixMe - converted to TS

packages/cli/src/commands/server/webSocketProxy.js → packages/cli/src/commands/server/webSocketProxy.ts

@@ -9,18 +9,21 @@
 
 import ws from 'ws';
 import {logger} from '@react-native-community/cli-tools';
+import {Server as HttpServer} from 'http';
+import {Server as HttpsServer} from 'https';
 
-function attachToServer(server, path) {
+type Server = HttpServer | HttpsServer;
+function attachToServer(server: Server, path: string) {
   const WebSocketServer = ws.Server;
   const wss = new WebSocketServer({
     server,
     path,
   });
 
-  let debuggerSocket;
-  let clientSocket;
+  let debuggerSocket: ws | null;
+  let clientSocket: ws | null;
 
-  function send(dest, message) {
+  function send(dest: ws | null, message: ws.Data) {
     if (!dest) {
       return;
     }
@@ -45,7 +48,8 @@ function attachToServer(server, path) {
     send(debuggerSocket, JSON.stringify({method: '$disconnected'}));
   };
 
-  wss.on('connection', connection => {
+  wss.on('connection', (connection: ws) => {
+    // @ts-ignore current definition of ws does not have upgradeReq type
     const {url} = connection.upgradeReq;
 
     if (url.indexOf('role=debugger') > -1) {
@@ -54,13 +58,18 @@ function attachToServer(server, path) {
         return;
       }
       debuggerSocket = connection;
-      debuggerSocket.onerror = debuggerSocketCloseHandler;
-      debuggerSocket.onclose = debuggerSocketCloseHandler;
-      debuggerSocket.onmessage = ({data}) => send(clientSocket, data);
+      if (debuggerSocket) {
+        debuggerSocket.onerror = debuggerSocketCloseHandler;
+        debuggerSocket.onclose = debuggerSocketCloseHandler;
+        debuggerSocket.onmessage = ({data}) => send(clientSocket, data);
+      }
     } else if (url.indexOf('role=client') > -1) {
       if (clientSocket) {
+        // @ts-ignore not nullable with current type definition of ws
         clientSocket.onerror = null;
+        // @ts-ignore not nullable with current type definition of ws
         clientSocket.onclose = null;
+        // @ts-ignore not nullable with current type definition of ws
         clientSocket.onmessage = null;
         clientSocket.close(1011, 'Another client connected');
       }

yarn.lock

@@ -2149,6 +2149,13 @@
   dependencies:
     "@types/node" "*"
 
+"@types/node-notifier@^5.4.0":
+  version "5.4.0"
+  resolved "https://registry.yarnpkg.com/@types/node-notifier/-/node-notifier-5.4.0.tgz#4e66c85eb41cce8387b4cd9c6c67852be41a99db"
+  integrity sha512-M1XvCG6Rwej6+W0+kWultE46YS7erOy+W7suRmXtKwLGT3ytj6YEe9lqo47nRfL1xILzg9xJpKeNczIsWR8ymw==
+  dependencies:
+    "@types/node" "*"
+
 "@types/node@*":
   version "12.0.0"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-12.0.0.tgz#d11813b9c0ff8aaca29f04cbc12817f4c7d656e5"
@@ -2182,6 +2189,13 @@
   resolved "https://registry.yarnpkg.com/@types/wcwidth/-/wcwidth-1.0.0.tgz#a58f4673050f98c46ae8f852340889343b21a1f5"
   integrity sha512-X/WFfwGCIisEnd9EOSsX/jt7BHPDkcvQVYwVzc1nsE2K5bC56mWKnmNs0wyjcGcQsP7Wxq2zWSmhDDbF5Z7dDg==
 
+"@types/ws@^6.0.3":
+  version "6.0.3"
+  resolved "https://registry.yarnpkg.com/@types/ws/-/ws-6.0.3.tgz#b772375ba59d79066561c8d87500144d674ba6b3"
+  integrity sha512-yBTM0P05Tx9iXGq00BbJPo37ox68R5vaGTXivs6RGh/BQ6QP5zqZDGWdAO6JbRE/iR1l80xeGAwCQS2nMV9S/w==
+  dependencies:
+    "@types/node" "*"
+
 "@types/xmldoc@^1.1.4":
   version "1.1.4"
   resolved "https://registry.yarnpkg.com/@types/xmldoc/-/xmldoc-1.1.4.tgz#5867d4e29739719c633bf16413c5a4a4c1c3c802"