From 85e544afd95a5890761a613263a5eba0c9a18a93 Mon Sep 17 00:00:00 2001
From: Damien Arrachequesne <damien.arrachequesne@gmail.com>
Date: Thu, 4 Jun 2020 14:42:12 +0200
Subject: [PATCH] fix: remove explicit require of uws

So that bundlers like webpack do not try to include it in the build.

As a side-effect, any implementation which matches the API of the ws
module can now be used.

Before that change, you had to explicitly exclude uws:

```
// webpack.config.js
module.exports = {
  // ...
  externals: {
     uws: 'uws'
  }
};
```

Related: https://github.com/socketio/engine.io/issues/575

Backported from master: https://github.com/socketio/engine.io/commit/82cdca23bab0ed69b61b60961900d456a3065e6a
---
 lib/server.js | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/lib/server.js b/lib/server.js
index 3fbee3e07..6d998e8fb 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -102,12 +102,8 @@ Server.prototype.init = function () {
 
   if (this.ws) this.ws.close();
 
-  var wsModule;
-  switch (this.wsEngine) {
-    case 'uws': wsModule = require('uws'); break;
-    case 'ws': wsModule = require('ws'); break;
-    default: throw new Error('unknown wsEngine');
-  }
+  // add explicit require for bundlers like webpack
+  var wsModule = this.wsEngine === 'ws' ? require('ws') : require(this.wsEngine);
   this.ws = new wsModule.Server({
     noServer: true,
     clientTracking: false,