Use helper util for global object

This makes the library use `self` when `global` and `window` are
undefined, fixing a compatibility issue with some service worker
contexts.

src/common/lib/util/logger.ts

@@ -1,4 +1,5 @@
 import Platform from 'common/platform';
+import * as Utils from 'common/lib/util/utils';
 
 export type LoggerOptions = {
   handler: LoggerFunction;
@@ -7,7 +8,7 @@ export type LoggerOptions = {
 type LoggerFunction = (...args: string[]) => void;
 
 // Workaround for salesforce lightning locker compatibility
-let globalOrWindow = global || window;
+let globalObject = Utils.getGlobalObject();
 
 enum LogLevels {
   None = 0,
@@ -47,7 +48,7 @@ const getDefaultLoggers = (): [Function, Function] => {
   /* Can't just check for console && console.log; fails in IE <=9 */
   if (
     (typeof Window === 'undefined' && typeof WorkerGlobalScope === 'undefined') /* node */ ||
-    typeof globalOrWindow?.console?.log?.apply === 'function' /* sensible browsers */
+    typeof globalObject?.console?.log?.apply === 'function' /* sensible browsers */
   ) {
     consoleLogger = function (...args: unknown[]) {
       console.log.apply(console, args);
@@ -57,7 +58,7 @@ const getDefaultLoggers = (): [Function, Function] => {
           console.warn.apply(console, args);
         }
       : consoleLogger;
-  } else if (globalOrWindow?.console.log as unknown) {
+  } else if (globalObject?.console.log as unknown) {
     /* IE <= 9 with the console open -- console.log does not
      * inherit from Function, so has no apply method */
     consoleLogger = errorLogger = function () {

src/platform/web/lib/transport/jsonptransport.ts

@@ -13,14 +13,14 @@ import { TryConnectCallback } from 'common/lib/transport/transport';
 import XHRStates from 'common/constants/XHRStates';
 
 // Workaround for salesforce lightning locker compatibility
-let globalOrWindow = (global || window) as unknown as {
+let globalObject = Utils.getGlobalObject() as unknown as {
   _ablyjs_jsonp: Record<string, unknown>;
   JSONPTransport: typeof JSONPTransport;
 };
 
 const noop = function () {};
 /* Can't just use window.Ably, as that won't exist if using the commonjs version. */
-const _: Record<string, unknown> = (globalOrWindow._ablyjs_jsonp = {});
+const _: Record<string, unknown> = (globalObject._ablyjs_jsonp = {});
 
 /* express strips out parantheses from the callback!
  * Kludge to still alow its responses to work, while not keeping the
@@ -264,7 +264,7 @@ export class Request extends EventEmitter {
 }
 
 export default function (connectionManager: typeof ConnectionManager): typeof JSONPTransport {
-  globalOrWindow.JSONPTransport = JSONPTransport;
+  globalObject.JSONPTransport = JSONPTransport;
   if (JSONPTransport.isAvailable()) {
     connectionManager.supportedTransports[shortName] = JSONPTransport;
   }

src/platform/web/platform.ts

@@ -1,8 +1,9 @@
 import msgpack from './lib/util/msgpack';
 import { IPlatform, TypedArray } from '../../common/types/IPlatform';
+import * as Utils from 'common/lib/util/utils';
 
 // Workaround for salesforce lightning locker compat
-const globalOrWindow = global || window;
+const globalObject = Utils.getGlobalObject();
 
 declare var msCrypto: typeof crypto; // for IE11
 
@@ -16,12 +17,12 @@ function allowComet() {
   /* xhr requests from local files are unreliable in some browsers, such as Chrome 65 and higher -- see eg
    * https://stackoverflow.com/questions/49256429/chrome-65-unable-to-make-post-requests-from-local-files-to-flask
    * So if websockets are supported, then just forget about comet transports and use that */
-  const loc = globalOrWindow.location;
-  return !globalOrWindow.WebSocket || !loc || !loc.origin || loc.origin.indexOf('http') > -1;
+  const loc = globalObject.location;
+  return !globalObject.WebSocket || !loc || !loc.origin || loc.origin.indexOf('http') > -1;
 }
 
-const userAgent = globalOrWindow.navigator && globalOrWindow.navigator.userAgent.toString();
-const currentUrl = globalOrWindow.location && globalOrWindow.location.href;
+const userAgent = globalObject.navigator && globalObject.navigator.userAgent.toString();
+const currentUrl = globalObject.location && globalObject.location.href;
 
 const Platform: IPlatform = {
   agent: 'browser',
@@ -30,36 +31,36 @@ const Platform: IPlatform = {
   currentUrl: currentUrl,
   noUpgrade: userAgent && !!userAgent.match(/MSIE\s8\.0/),
   binaryType: 'arraybuffer',
-  WebSocket: globalOrWindow.WebSocket,
-  xhrSupported: globalOrWindow.XMLHttpRequest && 'withCredentials' in new XMLHttpRequest(),
+  WebSocket: globalObject.WebSocket,
+  xhrSupported: globalObject.XMLHttpRequest && 'withCredentials' in new XMLHttpRequest(),
   jsonpSupported: typeof document !== 'undefined',
   allowComet: allowComet(),
   streamingSupported: true,
   useProtocolHeartbeats: true,
   createHmac: null,
   msgpack: msgpack,
-  supportsBinary: !!globalOrWindow.TextDecoder,
+  supportsBinary: !!globalObject.TextDecoder,
   preferBinary: false,
-  ArrayBuffer: globalOrWindow.ArrayBuffer,
-  atob: globalOrWindow.atob,
+  ArrayBuffer: globalObject.ArrayBuffer,
+  atob: globalObject.atob,
   nextTick:
-    typeof globalOrWindow.setImmediate !== 'undefined'
-      ? globalOrWindow.setImmediate.bind(globalOrWindow)
+    typeof globalObject.setImmediate !== 'undefined'
+      ? globalObject.setImmediate.bind(globalObject)
       : function (f: () => void) {
           setTimeout(f, 0);
         },
-  addEventListener: globalOrWindow.addEventListener,
+  addEventListener: globalObject.addEventListener,
   inspect: JSON.stringify,
   stringByteSize: function (str: string) {
     /* str.length will be an underestimate for non-ascii strings. But if we're
      * in a browser too old to support TextDecoder, not much we can do. Better
      * to underestimate, so if we do go over-size, the server will reject the
      * message */
-    return (globalOrWindow.TextDecoder && new globalOrWindow.TextEncoder().encode(str).length) || str.length;
+    return (globalObject.TextDecoder && new globalObject.TextEncoder().encode(str).length) || str.length;
   },
-  TextEncoder: globalOrWindow.TextEncoder,
-  TextDecoder: globalOrWindow.TextDecoder,
-  Promise: globalOrWindow.Promise,
+  TextEncoder: globalObject.TextEncoder,
+  TextDecoder: globalObject.TextDecoder,
+  Promise: globalObject.Promise,
   getRandomValues: (function (crypto) {
     if (crypto === undefined) {
       return undefined;
@@ -70,7 +71,7 @@ const Platform: IPlatform = {
         callback(null);
       }
     };
-  })(globalOrWindow.crypto || msCrypto),
+  })(globalObject.crypto || msCrypto),
 };
 
 export default Platform;