Don't clobber global space in WS provider (#1922)

* Don't clbber global space in WS provider

* Re-use getWSClass

packages/rpc-provider/src/ws/Provider.ts

@@ -5,13 +5,12 @@
 
 import { JsonRpcResponse, ProviderInterface, ProviderInterfaceCallback, ProviderInterfaceEmitted, ProviderInterfaceEmitCb } from '../types';
 
-import './polyfill';
-
 import EventEmitter from 'eventemitter3';
 import { assert, isNull, isUndefined, logger } from '@polkadot/util';
 
 import Coder from '../coder';
 import defaults from '../defaults';
+import getWSClass from './getWSClass';
 
 type CallbackHandler = (error?: null | Error, value?: any) => void;
 
@@ -122,9 +121,11 @@ export default class WsProvider implements WSProviderInterface {
    * @description The [[WsProvider]] connects automatically by default, however if you decided otherwise, you may
    * connect manually using this method.
    */
-  public connect (): void {
+  public async connect (): Promise<void> {
     try {
-      this.#websocket = new WebSocket(this.#endpoint);
+      const WS = await getWSClass();
+
+      this.#websocket = new WS(this.#endpoint);
       this.#websocket.onclose = this.#onSocketClose;
       this.#websocket.onerror = this.#onSocketError;
       this.#websocket.onmessage = this.#onSocketMessage;

packages/rpc-provider/src/ws/getWSClass.spec.ts

@@ -5,10 +5,11 @@
 import { Constructor } from '@polkadot/types/types';
 
 import { Global } from './../mock/types';
+import getWSClass from './getWSClass';
 
 declare const global: Global;
 
-describe('ws/polyfill', (): void => {
+describe('getWebScoket', (): void => {
   let origWs: Constructor<WebSocket>;
 
   beforeEach((): void => {
@@ -19,17 +20,19 @@ describe('ws/polyfill', (): void => {
     global.WebSocket = origWs;
   });
 
-  it('polyfills with no exceptions (with WebSocket)', (): void => {
+  it('polyfills with no exceptions (with WebSocket)', async (): Promise<void> => {
     (global as any).WebSocket = undefined;
-    require('./polyfill');
 
-    expect(global.WebSocket).toBeDefined();
+    const WS = await getWSClass();
+
+    expect(WS).toBeDefined();
   });
 
-  it('polyfills with no exceptions (without WebSocket)', (): void => {
+  it('polyfills with no exceptions (without WebSocket)', async (): Promise<void> => {
     (global as any).WebSocket = (): boolean => true;
-    require('./polyfill');
 
-    expect(global.WebSocket).toBeDefined();
+    const WS = await getWSClass();
+
+    expect(WS).toBeDefined();
   });
 });

packages/rpc-provider/src/ws/getWSClass.ts

@@ -0,0 +1,13 @@
+// Copyright 2017-2020 @polkadot/rpc-provider authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+export default async function getWSClass (): Promise<typeof WebSocket> {
+  if (typeof WebSocket === 'undefined') {
+    const { w3cwebsocket } = await import('websocket');
+
+    return w3cwebsocket as unknown as typeof WebSocket;
+  }
+
+  return WebSocket;
+}

packages/rpc-provider/src/ws/polyfill.ts

@@ -1,7 +0,0 @@
-// Copyright 2017-2020 @polkadot/rpc-provider authors & contributors
-// This software may be modified and distributed under the terms
-// of the Apache-2.0 license. See the LICENSE file for details.
-
-if (typeof WebSocket === 'undefined') {
-  (global as any).WebSocket = require('websocket').w3cwebsocket;
-}