chore(release): 3.0.1

Diff: https://github.com/socketio/socket.io/compare/3.0.0...3.0.1
docs(examples): update examples to Socket.IO v3
2026-01-11 16:08:24 -05:00 · 2020-11-09 10:27:58 +01:00 · 2020-11-09 10:19:40 +01:00 · 2020-11-09 08:58:14 +01:00 · 2020-11-08 00:07:56 +01:00 · 2020-11-05 22:25:35 +01:00
32 changed files with 11900 additions and 857 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,168 @@
+## [3.0.1](https://github.com/socketio/socket.io/compare/3.0.0...3.0.1) (2020-11-09)
+
+
+### Bug Fixes
+
+* export ServerOptions and Namespace types ([#3684](https://github.com/socketio/socket.io/issues/3684)) ([f62f180](https://github.com/socketio/socket.io/commit/f62f180edafdd56d8a8a277e092bc66df0c5f07f))
+* **typings:** update the signature of the emit method ([50671d9](https://github.com/socketio/socket.io/commit/50671d984a81535a6a15c704546ca7465e2ea295))
+
+
+# [3.0.0](https://github.com/socketio/socket.io/compare/2.3.0...3.0.0) (2020-11-05)
+
+### Bug Fixes
+
+* close clients with no namespace ([91cd255](https://github.com/socketio/socket.io/commit/91cd255ba76ff6a780c62740f9f5cd3a76f5d7c7))
+
+### Features
+
+* emit an Error object upon middleware error ([54bf4a4](https://github.com/socketio/socket.io/commit/54bf4a44e9e896dfb64764ee7bd4e8823eb7dc7b))
+* serve msgpack bundle ([aa7574f](https://github.com/socketio/socket.io/commit/aa7574f88471aa30ae472a5cddf1000a8baa70fd))
+* add support for catch-all listeners ([5c73733](https://github.com/socketio/socket.io/commit/5c737339858d59eab4b5ee2dd6feff0e82c4fe5a))
+* make Socket#join() and Socket#leave() synchronous ([129c641](https://github.com/socketio/socket.io/commit/129c6417bd818bc8b4e1b831644323876e627c13))
+* remove prod dependency to socket.io-client ([7603da7](https://github.com/socketio/socket.io/commit/7603da71a535481e3fc60e38b013abf78516d322))
+* move binary detection back to the parser ([669592d](https://github.com/socketio/socket.io/commit/669592d120409a5cf00f128070dee6d22259ba4f))
+* add ES6 module export ([8b6b100](https://github.com/socketio/socket.io/commit/8b6b100c284ccce7d85e55659e3397f533916847))
+* do not reuse the Engine.IO id ([2875d2c](https://github.com/socketio/socket.io/commit/2875d2cfdfa463e64cb520099749f543bbc4eb15))
+* remove Server#set() method ([029f478](https://github.com/socketio/socket.io/commit/029f478992f59b1eb5226453db46363a570eea46))
+* remove Socket#rooms object ([1507b41](https://github.com/socketio/socket.io/commit/1507b416d584381554d1ed23c9aaf3b650540071))
+* remove the 'origins' option ([a8c0600](https://github.com/socketio/socket.io/commit/a8c06006098b512ba1b8b8df82777349db486f41))
+* remove the implicit connection to the default namespace ([3289f7e](https://github.com/socketio/socket.io/commit/3289f7ec376e9ec88c2f90e2735c8ca8d01c0e97))
+* throw upon reserved event names ([4bd5b23](https://github.com/socketio/socket.io/commit/4bd5b2339a66a5a675e20f689fff2e70ff12d236))
+
+### BREAKING CHANGES
+
+* the Socket#use() method is removed (see [5c73733](https://github.com/socketio/socket.io/commit/5c737339858d59eab4b5ee2dd6feff0e82c4fe5a))
+
+* Socket#join() and Socket#leave() do not accept a callback argument anymore.
+
+Before:
+
+```js
+socket.join("room1", () => {
+ io.to("room1").emit("hello");
+});
+```
+
+After:
+
+```js
+socket.join("room1");
+io.to("room1").emit("hello");
+// or await socket.join("room1"); for custom adapters
+```
+
+* the "connected" map is renamed to "sockets"
+* the Socket#binary() method is removed, as this use case is now covered by the ability to provide your own parser.
+* the 'origins' option is removed
+
+Before:
+
+```js
+new Server(3000, {
+  origins: ["https://example.com"]
+});
+```
+
+The 'origins' option was used in the allowRequest method, in order to
+determine whether the request should pass or not. And the Engine.IO
+server would implicitly add the necessary Access-Control-Allow-xxx
+headers.
+
+After:
+
+```js
+new Server(3000, {
+  cors: {
+    origin: "https://example.com",
+    methods: ["GET", "POST"],
+    allowedHeaders: ["content-type"]
+  }
+});
+```
+
+The already existing 'allowRequest' option can be used for validation:
+
+```js
+new Server(3000, {
+  allowRequest: (req, callback) => {
+    callback(null, req.headers.referer.startsWith("https://example.com"));
+  }
+});
+```
+
+* Socket#rooms is now a Set instead of an object
+
+* Namespace#connected is now a Map instead of an object
+
+* there is no more implicit connection to the default namespace:
+
+```js
+// client-side
+const socket = io("/admin");
+
+// server-side
+io.on("connect", socket => {
+  // not triggered anymore
+})
+
+io.use((socket, next) => {
+  // not triggered anymore
+});
+
+io.of("/admin").use((socket, next) => {
+  // triggered
+});
+```
+
+* the Server#set() method was removed
+
+This method was kept for backward-compatibility with pre-1.0 versions.
+
+
+# [3.0.0-rc4](https://github.com/socketio/socket.io/compare/3.0.0-rc3...3.0.0-rc4) (2020-10-30)
+
+
+### Features
+
+* emit an Error object upon middleware error ([54bf4a4](https://github.com/socketio/socket.io/commit/54bf4a44e9e896dfb64764ee7bd4e8823eb7dc7b))
+* serve msgpack bundle ([aa7574f](https://github.com/socketio/socket.io/commit/aa7574f88471aa30ae472a5cddf1000a8baa70fd))
+
+
+
+# [3.0.0-rc3](https://github.com/socketio/socket.io/compare/3.0.0-rc2...3.0.0-rc3) (2020-10-26)
+
+
+### Features
+
+* add support for catch-all listeners ([5c73733](https://github.com/socketio/socket.io/commit/5c737339858d59eab4b5ee2dd6feff0e82c4fe5a))
+* make Socket#join() and Socket#leave() synchronous ([129c641](https://github.com/socketio/socket.io/commit/129c6417bd818bc8b4e1b831644323876e627c13))
+* remove prod dependency to socket.io-client ([7603da7](https://github.com/socketio/socket.io/commit/7603da71a535481e3fc60e38b013abf78516d322))
+
+
+### BREAKING CHANGES
+
+* the Socket#use() method is removed (see [5c73733](https://github.com/socketio/socket.io/commit/5c737339858d59eab4b5ee2dd6feff0e82c4fe5a))
+
+* Socket#join() and Socket#leave() do not accept a callback argument anymore.
+
+Before:
+
+```js
+socket.join("room1", () => {
+ io.to("room1").emit("hello");
+});
+```
+
+After:
+
+```js
+socket.join("room1");
+io.to("room1").emit("hello");
+// or await socket.join("room1"); for custom adapters
+```
+
+
+
 # [3.0.0-rc2](https://github.com/socketio/socket.io/compare/3.0.0-rc1...3.0.0-rc2) (2020-10-15)


--- a/client-dist/socket.io.js
+++ b/client-dist/socket.io.js
--- a/client-dist/socket.io.js.map
+++ b/client-dist/socket.io.js.map
--- a/client-dist/socket.io.min.js
+++ b/client-dist/socket.io.min.js
--- a/client-dist/socket.io.min.js.map
+++ b/client-dist/socket.io.min.js.map
--- a/client-dist/socket.io.msgpack.min.js
+++ b/client-dist/socket.io.msgpack.min.js
--- a/client-dist/socket.io.msgpack.min.js.map
+++ b/client-dist/socket.io.msgpack.min.js.map
--- a/examples/chat/README.md
+++ b/examples/chat/README.md
@@ -1,7 +1,7 @@

 # Socket.IO Chat

-A simple chat demo for socket.io
+A simple chat demo for Socket.IO

 ## How to use

--- a/examples/chat/index.js
+++ b/examples/chat/index.js
@@ -1,10 +1,10 @@
 // Setup basic express server
-var express = require('express');
-var app = express();
-var path = require('path');
-var server = require('http').createServer(app);
-var io = require('socket.io')(server);
-var port = process.env.PORT || 3000;
+const express = require('express');
+const app = express();
+const path = require('path');
+const server = require('http').createServer(app);
+const io = require('socket.io')(server);
+const port = process.env.PORT || 3000;

 server.listen(port, () => {
  console.log('Server listening at port %d', port);
@@ -15,10 +15,10 @@ app.use(express.static(path.join(__dirname, 'public')));

 // Chatroom

-var numUsers = 0;
+let numUsers = 0;

 io.on('connection', (socket) => {
-  var addedUser = false;
+  let addedUser = false;

  // when the client emits 'new message', this listens and executes
  socket.on('new message', (data) => {
--- a/examples/chat/package-lock.json
+++ b/examples/chat/package-lock.json
@@ -13,54 +13,16 @@
        "negotiator": "0.6.2"
      }
    },
-    "after": {
-      "version": "0.8.2",
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      "integrity": "sha1-ml9pkFGx5wczKPKgCJaLZOopVdI="
    },
-    "arraybuffer.slice": {
-      "version": "0.0.7",
-      "resolved": "https://registry.npmjs.org/arraybuffer.slice/-/arraybuffer.slice-0.0.7.tgz",
-      "integrity": "sha512-wGUIVQXuehL5TCqQun8OW81jGzAWycqzFF8lFp+GOM5BXLYj3bKNsYC4daB7n6XjCqxQA/qgTJ+8ANR3acjrog=="
-    },
-    "async-limiter": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/async-limiter/-/async-limiter-1.0.1.tgz",
-      "integrity": "sha512-csOlWGAcRFJaI6m+F2WKdnMKr4HhdhFVBk0H/QbJFMCr+uO2kwohwXQPxw/9OCxp05r5ghVBFSyioixx3gfkNQ=="
-    },
-    "backo2": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/backo2/-/backo2-1.0.2.tgz",
-      "integrity": "sha1-MasayLEpNjRj41s+u2n038+6eUc="
-    },
-    "base64-arraybuffer": {
-      "version": "0.1.5",
-      "resolved": "https://registry.npmjs.org/base64-arraybuffer/-/base64-arraybuffer-0.1.5.tgz",
-      "integrity": "sha1-c5JncZI7Whl0etZmqlzUv5xunOg="
-    },
    "base64id": {
      "version": "2.0.0",
      "resolved": "https://registry.npmjs.org/base64id/-/base64id-2.0.0.tgz",
      "integrity": "sha512-lGe34o6EHj9y3Kts9R4ZYs/Gr+6N7MCaMlIFA3F1R2O5/m7K06AxfSeO5530PEERE6/WyEg3lsuyw4GHlPZHog=="
    },
-    "better-assert": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/better-assert/-/better-assert-1.0.2.tgz",
-      "integrity": "sha1-QIZrnhueC1W0gYlDEeaPr/rrxSI=",
-      "requires": {
-        "callsite": "1.0.0"
-      }
-    },
-    "blob": {
-      "version": "0.0.5",
-      "resolved": "https://registry.npmjs.org/blob/-/blob-0.0.5.tgz",
-      "integrity": "sha512-gaqbzQPqOoamawKg0LGVd7SzLgXS+JH61oWprSLH+P+abTczqJbhTR8CmJ2u9/bUYNmHTGJx/UEmn6doAvvuig=="
-    },
    "body-parser": {
      "version": "1.19.0",
      "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.19.0.tgz",
@@ -83,25 +45,10 @@
      "resolved": "https://registry.npmjs.org/bytes/-/bytes-3.1.0.tgz",
      "integrity": "sha512-zauLjrfCG+xvoyaqLoV8bLVXXNGC4JqlxFCutSDWA6fJrTo2ZuvLYTqZ7aHBLZSMOopbzwv8f+wZcVzfVTI2Dg=="
    },
-    "callsite": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/callsite/-/callsite-1.0.0.tgz",
-      "integrity": "sha1-KAOY5dZkvXQDi28JBRU+borxvCA="
-    },
-    "component-bind": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/component-bind/-/component-bind-1.0.0.tgz",
-      "integrity": "sha1-AMYIq33Nk4l8AAllGx06jh5zu9E="
-    },
    "component-emitter": {
-      "version": "1.2.1",
-      "resolved": "https://registry.npmjs.org/component-emitter/-/component-emitter-1.2.1.tgz",
-      "integrity": "sha1-E3kY1teCg/ffemt8WmPhQOaUJeY="
-    },
-    "component-inherit": {
-      "version": "0.0.3",
-      "resolved": "https://registry.npmjs.org/component-inherit/-/component-inherit-0.0.3.tgz",
-      "integrity": "sha1-ZF/ErfWLcrZJ1crmUTVhnbJv8UM="
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/component-emitter/-/component-emitter-1.3.0.tgz",
+      "integrity": "sha512-Rd3se6QB+sO1TwqZjscQrurpEPIfO0/yYnSin6Q/rD3mOutHvUrCAhJub3r90uNb+SESBuE0QYoB90YdfatsRg=="
    },
    "content-disposition": {
      "version": "0.5.3",
@@ -126,6 +73,15 @@
      "resolved": "https://registry.npmjs.org/cookie-signature/-/cookie-signature-1.0.6.tgz",
      "integrity": "sha1-4wOogrNCzD7oylE6eZmXNNqzriw="
    },
+    "cors": {
+      "version": "2.8.5",
+      "resolved": "https://registry.npmjs.org/cors/-/cors-2.8.5.tgz",
+      "integrity": "sha512-KIHbLJqu73RGr/hnbrO9uBeixNGuvSQjul/jdFvS/KFSIH1hWVd1ng7zOHx+YrEfInLG7q4n6GHQ9cDtxv/P6g==",
+      "requires": {
+        "object-assign": "^4",
+        "vary": "^1"
+      }
+    },
    "debug": {
      "version": "2.6.9",
      "resolved": "https://registry.npmjs.org/debug/-/debug-2.6.9.tgz",
@@ -155,22 +111,23 @@
      "integrity": "sha1-rT/0yG7C0CkyL1oCw6mmBslbP1k="
    },
    "engine.io": {
-      "version": "3.4.1",
-      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-3.4.1.tgz",
-      "integrity": "sha512-8MfIfF1/IIfxuc2gv5K+XlFZczw/BpTvqBdl0E2fBLkYQp4miv4LuDTVtYt4yMyaIFLEr4vtaSgV4mjvll8Crw==",
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-4.0.1.tgz",
+      "integrity": "sha512-6EaSBxasBUwxRdf6B68SEYpD3tcrG80J4YTzHl/D+9Q+vM0AMHZabfYcc2WdnvEaQxZjX/UZsa+UdGoM0qQQkQ==",
      "requires": {
        "accepts": "~1.3.4",
        "base64id": "2.0.0",
-        "cookie": "0.3.1",
+        "cookie": "~0.4.1",
+        "cors": "~2.8.5",
        "debug": "~4.1.0",
-        "engine.io-parser": "~2.2.0",
+        "engine.io-parser": "~4.0.0",
        "ws": "^7.1.2"
      },
      "dependencies": {
        "cookie": {
-          "version": "0.3.1",
-          "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.3.1.tgz",
-          "integrity": "sha1-5+Ch+e9DtMi6klxcWpboBtFoc7s="
+          "version": "0.4.1",
+          "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.4.1.tgz",
+          "integrity": "sha512-ZwrFkGJxUR3EIoXtO+yVE69Eb7KlixbaeAWfBQB9vVsNn/o+Yw69gBWSSDK825hQNdN+wF8zELf3dFNl/kxkUA=="
        },
        "debug": {
          "version": "4.1.1",
@@ -187,58 +144,10 @@
        }
      }
    },
-    "engine.io-client": {
-      "version": "3.4.1",
-      "resolved": "https://registry.npmjs.org/engine.io-client/-/engine.io-client-3.4.1.tgz",
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-      "requires": {
-        "component-emitter": "1.2.1",
-        "component-inherit": "0.0.3",
-        "debug": "~4.1.0",
-        "engine.io-parser": "~2.2.0",
-        "has-cors": "1.1.0",
-        "indexof": "0.0.1",
-        "parseqs": "0.0.5",
-        "parseuri": "0.0.5",
-        "ws": "~6.1.0",
-        "xmlhttprequest-ssl": "~1.5.4",
-        "yeast": "0.1.2"
-      },
-      "dependencies": {
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-          "version": "4.1.1",
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-          "requires": {
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-        "ws": {
-          "version": "6.1.4",
-          "resolved": "https://registry.npmjs.org/ws/-/ws-6.1.4.tgz",
-          "integrity": "sha512-eqZfL+NE/YQc1/ZynhojeV8q+H050oR8AZ2uIev7RU10svA9ZnJUddHcOUZTJLinZ9yEfdA2kSATS2qZK5fhJA==",
-          "requires": {
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    "engine.io-parser": {
-      "version": "2.2.0",
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-      "requires": {
-        "after": "0.8.2",
-        "arraybuffer.slice": "~0.0.7",
-        "base64-arraybuffer": "0.1.5",
-        "blob": "0.0.5",
-        "has-binary2": "~1.0.2"
-      }
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-4.0.1.tgz",
+      "integrity": "sha512-v5aZK1hlckcJDGmHz3W8xvI3NUHYc9t8QtTbqdR5OaH3S9iJZilPubauOm+vLWOMMWzpE3hiq92l9lTAHamRCg=="
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    "escape-html": {
      "version": "1.0.3",
@@ -311,19 +220,6 @@
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      "integrity": "sha1-PYyt2Q2XZWn6g1qx+OSyOhBWBac="
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-    "has-binary2": {
-      "version": "1.0.3",
-      "resolved": "https://registry.npmjs.org/has-binary2/-/has-binary2-1.0.3.tgz",
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-      "requires": {
-        "isarray": "2.0.1"
-      }
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-    "has-cors": {
-      "version": "1.1.0",
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-      "integrity": "sha1-XkdHk/fqmEPRu5nCPu9J/xJv/zk="
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      "version": "1.7.2",
      "resolved": "https://registry.npmjs.org/http-errors/-/http-errors-1.7.2.tgz",
@@ -344,11 +240,6 @@
        "safer-buffer": ">= 2.1.2 < 3"
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-    "indexof": {
-      "version": "0.0.1",
-      "resolved": "https://registry.npmjs.org/indexof/-/indexof-0.0.1.tgz",
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@@ -359,11 +250,6 @@
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-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/isarray/-/isarray-2.0.1.tgz",
-      "integrity": "sha1-o32U7ZzaLVmGXJ92/llu4fM4dB4="
-    },
    "media-typer": {
      "version": "0.3.0",
      "resolved": "https://registry.npmjs.org/media-typer/-/media-typer-0.3.0.tgz",
@@ -407,10 +293,10 @@
      "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.2.tgz",
      "integrity": "sha512-hZXc7K2e+PgeI1eDBe/10Ard4ekbfrrqG8Ep+8Jmf4JID2bNg7NvCPOZN+kfF574pFQI7mum2AUqDidoKqcTOw=="
    },
-    "object-component": {
-      "version": "0.0.3",
-      "resolved": "https://registry.npmjs.org/object-component/-/object-component-0.0.3.tgz",
-      "integrity": "sha1-8MaapQ78lbhmwYb0AKM3acsvEpE="
+    "object-assign": {
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
+      "integrity": "sha1-IQmtx5ZYh8/AXLvUQsrIv7s2CGM="
    },
    "on-finished": {
      "version": "2.3.0",
@@ -420,22 +306,6 @@
        "ee-first": "1.1.1"
      }
    },
-    "parseqs": {
-      "version": "0.0.5",
-      "resolved": "https://registry.npmjs.org/parseqs/-/parseqs-0.0.5.tgz",
-      "integrity": "sha1-1SCKNzjkZ2bikbouoXNoSSGouJ0=",
-      "requires": {
-        "better-assert": "~1.0.0"
-      }
-    },
-    "parseuri": {
-      "version": "0.0.5",
-      "resolved": "https://registry.npmjs.org/parseuri/-/parseuri-0.0.5.tgz",
-      "integrity": "sha1-gCBKUNTbt3m/3G6+J3jZDkvOMgo=",
-      "requires": {
-        "better-assert": "~1.0.0"
-      }
-    },
    "parseurl": {
      "version": "1.3.3",
      "resolved": "https://registry.npmjs.org/parseurl/-/parseurl-1.3.3.tgz",
@@ -530,16 +400,16 @@
      "integrity": "sha512-JvdAWfbXeIGaZ9cILp38HntZSFSo3mWg6xGcJJsd+d4aRMOqauag1C63dJfDw7OaMYwEbHMOxEZ1lqVRYP2OAw=="
    },
    "socket.io": {
-      "version": "2.3.0",
-      "resolved": "https://registry.npmjs.org/socket.io/-/socket.io-2.3.0.tgz",
-      "integrity": "sha512-2A892lrj0GcgR/9Qk81EaY2gYhCBxurV0PfmmESO6p27QPrUK1J3zdns+5QPqvUYK2q657nSj0guoIil9+7eFg==",
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/socket.io/-/socket.io-3.0.0.tgz",
+      "integrity": "sha512-arLQtd+UoJ08NXBRBGUJDyQ9B+cc9WwD67hc5s1WQcs2DyAkYzI5HWg4U0CrFtK00kjyAWxBGhLwVbfOeMqz1A==",
      "requires": {
+        "accepts": "~1.3.4",
+        "base64id": "~2.0.0",
        "debug": "~4.1.0",
-        "engine.io": "~3.4.0",
-        "has-binary2": "~1.0.2",
-        "socket.io-adapter": "~1.1.0",
-        "socket.io-client": "2.3.0",
-        "socket.io-parser": "~3.4.0"
+        "engine.io": "~4.0.0",
+        "socket.io-adapter": "~2.0.3",
+        "socket.io-parser": "~4.0.1"
      },
      "dependencies": {
        "debug": {
@@ -558,79 +428,17 @@
      }
    },
    "socket.io-adapter": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/socket.io-adapter/-/socket.io-adapter-1.1.2.tgz",
-      "integrity": "sha512-WzZRUj1kUjrTIrUKpZLEzFZ1OLj5FwLlAFQs9kuZJzJi5DKdU7FsWc36SNmA8iDOtwBQyT8FkrriRM8vXLYz8g=="
-    },
-    "socket.io-client": {
-      "version": "2.3.0",
-      "resolved": "https://registry.npmjs.org/socket.io-client/-/socket.io-client-2.3.0.tgz",
-      "integrity": "sha512-cEQQf24gET3rfhxZ2jJ5xzAOo/xhZwK+mOqtGRg5IowZsMgwvHwnf/mCRapAAkadhM26y+iydgwsXGObBB5ZdA==",
-      "requires": {
-        "backo2": "1.0.2",
-        "base64-arraybuffer": "0.1.5",
-        "component-bind": "1.0.0",
-        "component-emitter": "1.2.1",
-        "debug": "~4.1.0",
-        "engine.io-client": "~3.4.0",
-        "has-binary2": "~1.0.2",
-        "has-cors": "1.1.0",
-        "indexof": "0.0.1",
-        "object-component": "0.0.3",
-        "parseqs": "0.0.5",
-        "parseuri": "0.0.5",
-        "socket.io-parser": "~3.3.0",
-        "to-array": "0.1.4"
-      },
-      "dependencies": {
-        "debug": {
-          "version": "4.1.1",
-          "resolved": "https://registry.npmjs.org/debug/-/debug-4.1.1.tgz",
-          "integrity": "sha512-pYAIzeRo8J6KPEaJ0VWOh5Pzkbw/RetuzehGM7QRRX5he4fPHx2rdKMB256ehJCkX+XRQm16eZLqLNS8RSZXZw==",
-          "requires": {
-            "ms": "^2.1.1"
-          }
-        },
-        "ms": {
-          "version": "2.1.2",
-          "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
-          "integrity": "sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w=="
-        },
-        "socket.io-parser": {
-          "version": "3.3.0",
-          "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-3.3.0.tgz",
-          "integrity": "sha512-hczmV6bDgdaEbVqhAeVMM/jfUfzuEZHsQg6eOmLgJht6G3mPKMxYm75w2+qhAQZ+4X+1+ATZ+QFKeOZD5riHng==",
-          "requires": {
-            "component-emitter": "1.2.1",
-            "debug": "~3.1.0",
-            "isarray": "2.0.1"
-          },
-          "dependencies": {
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-              "version": "3.1.0",
-              "resolved": "https://registry.npmjs.org/debug/-/debug-3.1.0.tgz",
-              "integrity": "sha512-OX8XqP7/1a9cqkxYw2yXss15f26NKWBpDXQd0/uK/KPqdQhxbPa994hnzjcE2VqQpDslf55723cKPUOGSmMY3g==",
-              "requires": {
-                "ms": "2.0.0"
-              }
-            },
-            "ms": {
-              "version": "2.0.0",
-              "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
-              "integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
-            }
-          }
-        }
-      }
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/socket.io-adapter/-/socket.io-adapter-2.0.3.tgz",
+      "integrity": "sha512-2wo4EXgxOGSFueqvHAdnmi5JLZzWqMArjuP4nqC26AtLh5PoCPsaRbRdah2xhcwTAMooZfjYiNVNkkmmSMaxOQ=="
    },
    "socket.io-parser": {
-      "version": "3.4.0",
-      "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-3.4.0.tgz",
-      "integrity": "sha512-/G/VOI+3DBp0+DJKW4KesGnQkQPFmUCbA/oO2QGT6CWxU7hLGWqU3tyuzeSK/dqcyeHsQg1vTe9jiZI8GU9SCQ==",
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.0.1.tgz",
+      "integrity": "sha512-5JfNykYptCwU2lkOI0ieoePWm+6stEhkZ2UnLDjqnE1YEjUlXXLd1lpxPZ+g+h3rtaytwWkWrLQCaJULlGqjOg==",
      "requires": {
-        "component-emitter": "1.2.1",
-        "debug": "~4.1.0",
-        "isarray": "2.0.1"
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0"
      },
      "dependencies": {
        "debug": {
@@ -653,11 +461,6 @@
      "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.5.0.tgz",
      "integrity": "sha1-Fhx9rBd2Wf2YEfQ3cfqZOBR4Yow="
    },
-    "to-array": {
-      "version": "0.1.4",
-      "resolved": "https://registry.npmjs.org/to-array/-/to-array-0.1.4.tgz",
-      "integrity": "sha1-F+bBH3PdTz10zaek/zI46a2b+JA="
-    },
    "toidentifier": {
      "version": "1.0.0",
      "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.0.tgz",
@@ -688,19 +491,9 @@
      "integrity": "sha1-IpnwLG3tMNSllhsLn3RSShj2NPw="
    },
    "ws": {
-      "version": "7.2.3",
-      "resolved": "https://registry.npmjs.org/ws/-/ws-7.2.3.tgz",
-      "integrity": "sha512-HTDl9G9hbkNDk98naoR/cHDws7+EyYMOdL1BmjsZXRUjf7d+MficC4B7HLUPlSiho0vg+CWKrGIt/VJBd1xunQ=="
-    },
-    "xmlhttprequest-ssl": {
-      "version": "1.5.5",
-      "resolved": "https://registry.npmjs.org/xmlhttprequest-ssl/-/xmlhttprequest-ssl-1.5.5.tgz",
-      "integrity": "sha1-wodrBhaKrcQOV9l+gRkayPQ5iz4="
-    },
-    "yeast": {
-      "version": "0.1.2",
-      "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
-      "integrity": "sha1-AI4G2AlDIMNy28L47XagymyKxBk="
+      "version": "7.4.0",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.4.0.tgz",
+      "integrity": "sha512-kyFwXuV/5ymf+IXhS6f0+eAFvydbaBW3zjpT6hUdAh/hbVjTIB5EHBGi0bPoCLSK2wcuz3BrEkB9LrYv1Nm4NQ=="
    }
  }
 }
--- a/examples/chat/package.json
+++ b/examples/chat/package.json
@@ -8,7 +8,7 @@
  "license": "BSD",
  "dependencies": {
    "express": "~4.17.1",
-    "socket.io": "~2.3.0"
+    "socket.io": "^3.0.0"
  },
  "scripts": {
    "start": "node index.js"
--- a/examples/es-modules/README.md
+++ b/examples/es-modules/README.md
@@ -0,0 +1,17 @@
+
+# Example with [ES modules](https://nodejs.org/api/esm.html)
+
+## How to use
+
+```
+# install the dependencies
+$ npm ci
+
+# start the server
+$ node server.js
+
+# start the client
+$ node client.js
+```
+
+You need Node.js `>=12.17.0`.
--- a/examples/es-modules/client.js
+++ b/examples/es-modules/client.js
@@ -0,0 +1,18 @@
+import { Manager } from "socket.io-client";
+
+const manager = new Manager("ws://localhost:8080");
+const socket = manager.socket("/");
+
+socket.on("connect", () => {
+  console.log(`connect ${socket.id}`);
+});
+
+socket.on("disconnect", () => {
+  console.log(`disconnect`);
+});
+
+setInterval(() => {
+  socket.emit("ping", () => {
+    console.log("pong");
+  });
+}, 1000);
--- a/examples/es-modules/package-lock.json
+++ b/examples/es-modules/package-lock.json
@@ -0,0 +1,217 @@
+{
+  "name": "es-modules",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "@types/component-emitter": {
+      "version": "1.2.10",
+      "resolved": "https://registry.npmjs.org/@types/component-emitter/-/component-emitter-1.2.10.tgz",
+      "integrity": "sha512-bsjleuRKWmGqajMerkzox19aGbscQX5rmmvvXl3wlIp5gMG1HgkiwPxsN5p070fBDKTNSPgojVbuY1+HWMbFhg=="
+    },
+    "accepts": {
+      "version": "1.3.7",
+      "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.7.tgz",
+      "integrity": "sha512-Il80Qs2WjYlJIBNzNkK6KYqlVMTbZLXgHx2oT0pU/fjRHyEp+PEfEPY0R3WCwAGVOtauxh1hOxNgIf5bv7dQpA==",
+      "requires": {
+        "mime-types": "~2.1.24",
+        "negotiator": "0.6.2"
+      }
+    },
+    "backo2": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/backo2/-/backo2-1.0.2.tgz",
+      "integrity": "sha1-MasayLEpNjRj41s+u2n038+6eUc="
+    },
+    "base64-arraybuffer": {
+      "version": "0.1.4",
+      "resolved": "https://registry.npmjs.org/base64-arraybuffer/-/base64-arraybuffer-0.1.4.tgz",
+      "integrity": "sha1-mBjHngWbE1X5fgQooBfIOOkLqBI="
+    },
+    "base64id": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/base64id/-/base64id-2.0.0.tgz",
+      "integrity": "sha512-lGe34o6EHj9y3Kts9R4ZYs/Gr+6N7MCaMlIFA3F1R2O5/m7K06AxfSeO5530PEERE6/WyEg3lsuyw4GHlPZHog=="
+    },
+    "component-bind": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/component-bind/-/component-bind-1.0.0.tgz",
+      "integrity": "sha1-AMYIq33Nk4l8AAllGx06jh5zu9E="
+    },
+    "component-emitter": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/component-emitter/-/component-emitter-1.3.0.tgz",
+      "integrity": "sha512-Rd3se6QB+sO1TwqZjscQrurpEPIfO0/yYnSin6Q/rD3mOutHvUrCAhJub3r90uNb+SESBuE0QYoB90YdfatsRg=="
+    },
+    "cookie": {
+      "version": "0.4.1",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.4.1.tgz",
+      "integrity": "sha512-ZwrFkGJxUR3EIoXtO+yVE69Eb7KlixbaeAWfBQB9vVsNn/o+Yw69gBWSSDK825hQNdN+wF8zELf3dFNl/kxkUA=="
+    },
+    "cors": {
+      "version": "2.8.5",
+      "resolved": "https://registry.npmjs.org/cors/-/cors-2.8.5.tgz",
+      "integrity": "sha512-KIHbLJqu73RGr/hnbrO9uBeixNGuvSQjul/jdFvS/KFSIH1hWVd1ng7zOHx+YrEfInLG7q4n6GHQ9cDtxv/P6g==",
+      "requires": {
+        "object-assign": "^4",
+        "vary": "^1"
+      }
+    },
+    "debug": {
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/debug/-/debug-4.1.1.tgz",
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+      "requires": {
+        "ms": "^2.1.1"
+      }
+    },
+    "engine.io": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-4.0.1.tgz",
+      "integrity": "sha512-6EaSBxasBUwxRdf6B68SEYpD3tcrG80J4YTzHl/D+9Q+vM0AMHZabfYcc2WdnvEaQxZjX/UZsa+UdGoM0qQQkQ==",
+      "requires": {
+        "accepts": "~1.3.4",
+        "base64id": "2.0.0",
+        "cookie": "~0.4.1",
+        "cors": "~2.8.5",
+        "debug": "~4.1.0",
+        "engine.io-parser": "~4.0.0",
+        "ws": "^7.1.2"
+      }
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+    "engine.io-client": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io-client/-/engine.io-client-4.0.1.tgz",
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+      "requires": {
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+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0",
+        "engine.io-parser": "~4.0.1",
+        "has-cors": "1.1.0",
+        "parseqs": "0.0.6",
+        "parseuri": "0.0.6",
+        "ws": "~7.2.1",
+        "xmlhttprequest-ssl": "~1.5.4",
+        "yeast": "0.1.2"
+      },
+      "dependencies": {
+        "ws": {
+          "version": "7.2.5",
+          "resolved": "https://registry.npmjs.org/ws/-/ws-7.2.5.tgz",
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+        }
+      }
+    },
+    "engine.io-parser": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-4.0.1.tgz",
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+    },
+    "has-cors": {
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+      "resolved": "https://registry.npmjs.org/has-cors/-/has-cors-1.1.0.tgz",
+      "integrity": "sha1-XkdHk/fqmEPRu5nCPu9J/xJv/zk="
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+    },
+    "mime-types": {
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+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.27.tgz",
+      "integrity": "sha512-JIhqnCasI9yD+SsmkquHBxTSEuZdQX5BuQnS2Vc7puQQQ+8yiP5AY5uWhpdv4YL4VM5c6iliiYWPgJ/nJQLp7w==",
+      "requires": {
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+      }
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+    "ms": {
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+      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
+      "integrity": "sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w=="
+    },
+    "negotiator": {
+      "version": "0.6.2",
+      "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.2.tgz",
+      "integrity": "sha512-hZXc7K2e+PgeI1eDBe/10Ard4ekbfrrqG8Ep+8Jmf4JID2bNg7NvCPOZN+kfF574pFQI7mum2AUqDidoKqcTOw=="
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+      "resolved": "https://registry.npmjs.org/parseuri/-/parseuri-0.0.6.tgz",
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+    },
+    "socket.io": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/socket.io/-/socket.io-3.0.0.tgz",
+      "integrity": "sha512-arLQtd+UoJ08NXBRBGUJDyQ9B+cc9WwD67hc5s1WQcs2DyAkYzI5HWg4U0CrFtK00kjyAWxBGhLwVbfOeMqz1A==",
+      "requires": {
+        "accepts": "~1.3.4",
+        "base64id": "~2.0.0",
+        "debug": "~4.1.0",
+        "engine.io": "~4.0.0",
+        "socket.io-adapter": "~2.0.3",
+        "socket.io-parser": "~4.0.1"
+      }
+    },
+    "socket.io-adapter": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/socket.io-adapter/-/socket.io-adapter-2.0.3.tgz",
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+    },
+    "socket.io-client": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/socket.io-client/-/socket.io-client-3.0.0.tgz",
+      "integrity": "sha512-NreA86JJSMMSyPomkpyWL+FeKB3wmsWbGbNvtoxPbodV7dEIWxwyOklYfhuTpJJDCpEFd55vET2/ZyYwJ66Bfg==",
+      "requires": {
+        "@types/component-emitter": "^1.2.10",
+        "backo2": "1.0.2",
+        "component-bind": "1.0.0",
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0",
+        "engine.io-client": "~4.0.0",
+        "parseuri": "0.0.6",
+        "socket.io-parser": "~4.0.1"
+      }
+    },
+    "socket.io-parser": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.0.1.tgz",
+      "integrity": "sha512-5JfNykYptCwU2lkOI0ieoePWm+6stEhkZ2UnLDjqnE1YEjUlXXLd1lpxPZ+g+h3rtaytwWkWrLQCaJULlGqjOg==",
+      "requires": {
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0"
+      }
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+    "vary": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
+      "integrity": "sha1-IpnwLG3tMNSllhsLn3RSShj2NPw="
+    },
+    "ws": {
+      "version": "7.4.0",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.4.0.tgz",
+      "integrity": "sha512-kyFwXuV/5ymf+IXhS6f0+eAFvydbaBW3zjpT6hUdAh/hbVjTIB5EHBGi0bPoCLSK2wcuz3BrEkB9LrYv1Nm4NQ=="
+    },
+    "xmlhttprequest-ssl": {
+      "version": "1.5.5",
+      "resolved": "https://registry.npmjs.org/xmlhttprequest-ssl/-/xmlhttprequest-ssl-1.5.5.tgz",
+      "integrity": "sha1-wodrBhaKrcQOV9l+gRkayPQ5iz4="
+    },
+    "yeast": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
+      "integrity": "sha1-AI4G2AlDIMNy28L47XagymyKxBk="
+    }
+  }
+}
--- a/examples/es-modules/package.json
+++ b/examples/es-modules/package.json
@@ -0,0 +1,15 @@
+{
+  "name": "es-modules",
+  "version": "1.0.0",
+  "description": "An example with ES modules (https://nodejs.org/api/esm.html)",
+  "type": "module",
+  "author": "Damien Arrachequesne",
+  "license": "MIT",
+  "engines": {
+    "node": ">=12.17.0"
+  },
+  "dependencies": {
+    "socket.io": "^3.0.0",
+    "socket.io-client": "^3.0.0"
+  }
+}
--- a/examples/es-modules/server.js
+++ b/examples/es-modules/server.js
@@ -0,0 +1,16 @@
+import { Server } from "socket.io";
+
+const io = new Server(8080);
+
+io.on("connect", (socket) => {
+  console.log(`connect ${socket.id}`);
+
+  socket.on("ping", (cb) => {
+    console.log("ping");
+    cb();
+  });
+
+  socket.on("disconnect", () => {
+    console.log(`disconnect ${socket.id}`);
+  });
+});
--- a/examples/typescript/client.ts
+++ b/examples/typescript/client.ts
@@ -0,0 +1,19 @@
+import { Manager } from "socket.io-client";
+
+const manager = new Manager("ws://localhost:8080");
+const socket = manager.socket("/");
+
+socket.on("connect", () => {
+    console.log(`connect ${socket.id}`);
+});
+
+socket.on("disconnect", () => {
+    console.log(`disconnect`);
+});
+
+setInterval(() => {
+    const start = Date.now();
+    socket.emit("ping", () => {
+        console.log(`pong (latency: ${Date.now() - start} ms)`);
+    });
+}, 1000);
--- a/examples/typescript/package-lock.json
+++ b/examples/typescript/package-lock.json
@@ -0,0 +1,268 @@
+{
+  "name": "typescript",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
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+      "resolved": "https://registry.npmjs.org/@types/component-emitter/-/component-emitter-1.2.10.tgz",
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+    },
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+      "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.7.tgz",
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+      "requires": {
+        "mime-types": "~2.1.24",
+        "negotiator": "0.6.2"
+      }
+    },
+    "arg": {
+      "version": "4.1.3",
+      "resolved": "https://registry.npmjs.org/arg/-/arg-4.1.3.tgz",
+      "integrity": "sha512-58S9QDqG0Xx27YwPSt9fJxivjYl432YCwfDMfZ+71RAqUrZef7LrKQZ3LHLOwCS4FLNBplP533Zx895SeOCHvA=="
+    },
+    "backo2": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/backo2/-/backo2-1.0.2.tgz",
+      "integrity": "sha1-MasayLEpNjRj41s+u2n038+6eUc="
+    },
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+      "resolved": "https://registry.npmjs.org/base64-arraybuffer/-/base64-arraybuffer-0.1.4.tgz",
+      "integrity": "sha1-mBjHngWbE1X5fgQooBfIOOkLqBI="
+    },
+    "base64id": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/base64id/-/base64id-2.0.0.tgz",
+      "integrity": "sha512-lGe34o6EHj9y3Kts9R4ZYs/Gr+6N7MCaMlIFA3F1R2O5/m7K06AxfSeO5530PEERE6/WyEg3lsuyw4GHlPZHog=="
+    },
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+      "resolved": "https://registry.npmjs.org/buffer-from/-/buffer-from-1.1.1.tgz",
+      "integrity": "sha512-MQcXEUbCKtEo7bhqEs6560Hyd4XaovZlO/k9V3hjVUF/zwW7KBVdSK4gIt/bzwS9MbR5qob+F5jusZsb0YQK2A=="
+    },
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+      "integrity": "sha1-AMYIq33Nk4l8AAllGx06jh5zu9E="
+    },
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+    },
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+    },
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+      "integrity": "sha512-KIHbLJqu73RGr/hnbrO9uBeixNGuvSQjul/jdFvS/KFSIH1hWVd1ng7zOHx+YrEfInLG7q4n6GHQ9cDtxv/P6g==",
+      "requires": {
+        "object-assign": "^4",
+        "vary": "^1"
+      }
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+      "requires": {
+        "ms": "^2.1.1"
+      }
+    },
+    "diff": {
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.2.tgz",
+      "integrity": "sha512-58lmxKSA4BNyLz+HHMUzlOEpg09FV+ev6ZMe3vJihgdxzgcwZ8VoEEPmALCZG9LmqfVoNMMKpttIYTVG6uDY7A=="
+    },
+    "engine.io": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-4.0.1.tgz",
+      "integrity": "sha512-6EaSBxasBUwxRdf6B68SEYpD3tcrG80J4YTzHl/D+9Q+vM0AMHZabfYcc2WdnvEaQxZjX/UZsa+UdGoM0qQQkQ==",
+      "requires": {
+        "accepts": "~1.3.4",
+        "base64id": "2.0.0",
+        "cookie": "~0.4.1",
+        "cors": "~2.8.5",
+        "debug": "~4.1.0",
+        "engine.io-parser": "~4.0.0",
+        "ws": "^7.1.2"
+      }
+    },
+    "engine.io-client": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io-client/-/engine.io-client-4.0.1.tgz",
+      "integrity": "sha512-3XXfWrEutlf1vg5PlS805bD+AgZXhRIKYAG04f1iCGOs70dWEYlZGfCZUNwPwNx05lBCKs1lIeL3SkLB0P++xw==",
+      "requires": {
+        "base64-arraybuffer": "0.1.4",
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0",
+        "engine.io-parser": "~4.0.1",
+        "has-cors": "1.1.0",
+        "parseqs": "0.0.6",
+        "parseuri": "0.0.6",
+        "ws": "~7.2.1",
+        "xmlhttprequest-ssl": "~1.5.4",
+        "yeast": "0.1.2"
+      },
+      "dependencies": {
+        "ws": {
+          "version": "7.2.5",
+          "resolved": "https://registry.npmjs.org/ws/-/ws-7.2.5.tgz",
+          "integrity": "sha512-C34cIU4+DB2vMyAbmEKossWq2ZQDr6QEyuuCzWrM9zfw1sGc0mYiJ0UnG9zzNykt49C2Fi34hvr2vssFQRS6EA=="
+        }
+      }
+    },
+    "engine.io-parser": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-4.0.1.tgz",
+      "integrity": "sha512-v5aZK1hlckcJDGmHz3W8xvI3NUHYc9t8QtTbqdR5OaH3S9iJZilPubauOm+vLWOMMWzpE3hiq92l9lTAHamRCg=="
+    },
+    "has-cors": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/has-cors/-/has-cors-1.1.0.tgz",
+      "integrity": "sha1-XkdHk/fqmEPRu5nCPu9J/xJv/zk="
+    },
+    "make-error": {
+      "version": "1.3.6",
+      "resolved": "https://registry.npmjs.org/make-error/-/make-error-1.3.6.tgz",
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+    },
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+      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.44.0.tgz",
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+    },
+    "mime-types": {
+      "version": "2.1.27",
+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.27.tgz",
+      "integrity": "sha512-JIhqnCasI9yD+SsmkquHBxTSEuZdQX5BuQnS2Vc7puQQQ+8yiP5AY5uWhpdv4YL4VM5c6iliiYWPgJ/nJQLp7w==",
+      "requires": {
+        "mime-db": "1.44.0"
+      }
+    },
+    "ms": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
+      "integrity": "sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w=="
+    },
+    "negotiator": {
+      "version": "0.6.2",
+      "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.2.tgz",
+      "integrity": "sha512-hZXc7K2e+PgeI1eDBe/10Ard4ekbfrrqG8Ep+8Jmf4JID2bNg7NvCPOZN+kfF574pFQI7mum2AUqDidoKqcTOw=="
+    },
+    "object-assign": {
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
+      "integrity": "sha1-IQmtx5ZYh8/AXLvUQsrIv7s2CGM="
+    },
+    "parseqs": {
+      "version": "0.0.6",
+      "resolved": "https://registry.npmjs.org/parseqs/-/parseqs-0.0.6.tgz",
+      "integrity": "sha512-jeAGzMDbfSHHA091hr0r31eYfTig+29g3GKKE/PPbEQ65X0lmMwlEoqmhzu0iztID5uJpZsFlUPDP8ThPL7M8w=="
+    },
+    "parseuri": {
+      "version": "0.0.6",
+      "resolved": "https://registry.npmjs.org/parseuri/-/parseuri-0.0.6.tgz",
+      "integrity": "sha512-AUjen8sAkGgao7UyCX6Ahv0gIK2fABKmYjvP4xmy5JaKvcbTRueIqIPHLAfq30xJddqSE033IOMUSOMCcK3Sow=="
+    },
+    "socket.io": {
+      "version": "3.0.0-rc3",
+      "resolved": "https://registry.npmjs.org/socket.io/-/socket.io-3.0.0-rc3.tgz",
+      "integrity": "sha512-AVIpRd7OTyhCgg5muz0AqeF06csptsnP8UP10ubLrnL7XKplJFDadUB9fEbwB3iLMpf1NT+YfqTBCVKHhpMlZA==",
+      "requires": {
+        "accepts": "~1.3.4",
+        "base64id": "~2.0.0",
+        "debug": "~4.1.0",
+        "engine.io": "~4.0.0",
+        "socket.io-adapter": "2.0.3-rc2",
+        "socket.io-parser": "4.0.1-rc3"
+      }
+    },
+    "socket.io-adapter": {
+      "version": "2.0.3-rc2",
+      "resolved": "https://registry.npmjs.org/socket.io-adapter/-/socket.io-adapter-2.0.3-rc2.tgz",
+      "integrity": "sha512-ic/fttwhpQ2Ry43ou6gOIeZgpGmsIUFQZ0Ww0DIpCerTKzDdLPG2+AEomG5SGXpppvtbwwesB7O9Azq0JiSs/g=="
+    },
+    "socket.io-client": {
+      "version": "3.0.0-rc3",
+      "resolved": "https://registry.npmjs.org/socket.io-client/-/socket.io-client-3.0.0-rc3.tgz",
+      "integrity": "sha512-9w67FZtTsGlDiwpobQ0l1UeLinx6LuFYEHGTcFRc5P5PyY/4M6ZI7nBFxIhjf0l8DTUfAJwllqzNxSqMW5nxhw==",
+      "requires": {
+        "@types/component-emitter": "^1.2.10",
+        "backo2": "1.0.2",
+        "component-bind": "1.0.0",
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0",
+        "engine.io-client": "~4.0.0",
+        "parseuri": "0.0.6",
+        "socket.io-parser": "4.0.1-rc3"
+      }
+    },
+    "socket.io-parser": {
+      "version": "4.0.1-rc3",
+      "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.0.1-rc3.tgz",
+      "integrity": "sha512-H85dvTVUOBMzquX5AojQvxRPCvH7jMkrhp2la+2gYn/uiS20sK1U8osWCMwU00oUITDUkjDTxLjw0fGkDTA76w==",
+      "requires": {
+        "component-emitter": "~1.3.0",
+        "debug": "~4.1.0"
+      }
+    },
+    "source-map": {
+      "version": "0.6.1",
+      "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",
+      "integrity": "sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g=="
+    },
+    "source-map-support": {
+      "version": "0.5.19",
+      "resolved": "https://registry.npmjs.org/source-map-support/-/source-map-support-0.5.19.tgz",
+      "integrity": "sha512-Wonm7zOCIJzBGQdB+thsPar0kYuCIzYvxZwlBa87yi/Mdjv7Tip2cyVbLj5o0cFPN4EVkuTwb3GDDyUx2DGnGw==",
+      "requires": {
+        "buffer-from": "^1.0.0",
+        "source-map": "^0.6.0"
+      }
+    },
+    "ts-node": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-9.0.0.tgz",
+      "integrity": "sha512-/TqB4SnererCDR/vb4S/QvSZvzQMJN8daAslg7MeaiHvD8rDZsSfXmNeNumyZZzMned72Xoq/isQljYSt8Ynfg==",
+      "requires": {
+        "arg": "^4.1.0",
+        "diff": "^4.0.1",
+        "make-error": "^1.1.1",
+        "source-map-support": "^0.5.17",
+        "yn": "3.1.1"
+      }
+    },
+    "vary": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
+      "integrity": "sha1-IpnwLG3tMNSllhsLn3RSShj2NPw="
+    },
+    "ws": {
+      "version": "7.3.1",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.3.1.tgz",
+      "integrity": "sha512-D3RuNkynyHmEJIpD2qrgVkc9DQ23OrN/moAwZX4L8DfvszsJxpjQuUq3LMx6HoYji9fbIOBY18XWBsAux1ZZUA=="
+    },
+    "xmlhttprequest-ssl": {
+      "version": "1.5.5",
+      "resolved": "https://registry.npmjs.org/xmlhttprequest-ssl/-/xmlhttprequest-ssl-1.5.5.tgz",
+      "integrity": "sha1-wodrBhaKrcQOV9l+gRkayPQ5iz4="
+    },
+    "yeast": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
+      "integrity": "sha1-AI4G2AlDIMNy28L47XagymyKxBk="
+    },
+    "yn": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/yn/-/yn-3.1.1.tgz",
+      "integrity": "sha512-Ux4ygGWsu2c7isFWe8Yu1YluJmqVhxqK2cLXNQA5AcC3QfbGNpM7fu0Y8b/z16pXLnFxZYvWhd3fhBY9DLmC6Q=="
+    }
+  }
+}
--- a/examples/typescript/package.json
+++ b/examples/typescript/package.json
@@ -0,0 +1,17 @@
+{
+  "name": "typescript",
+  "version": "1.0.0",
+  "description": "An example with TypeScript",
+  "private": true,
+  "scripts": {
+    "start:server": "ts-node server.ts",
+    "start:client": "ts-node client.ts"
+  },
+  "author": "Damien Arrachequesne",
+  "license": "MIT",
+  "dependencies": {
+    "socket.io": "beta",
+    "socket.io-client": "beta",
+    "ts-node": "^9.0.0"
+  }
+}
--- a/examples/typescript/server.ts
+++ b/examples/typescript/server.ts
@@ -0,0 +1,16 @@
+import { Server, Socket } from "socket.io";
+
+const io = new Server(8080);
+
+io.on("connect", (socket: Socket) => {
+    console.log(`connect ${socket.id}`);
+
+    socket.on("ping", (cb) => {
+        console.log("ping");
+        cb();
+    });
+
+    socket.on("disconnect", () => {
+        console.log(`disconnect ${socket.id}`);
+    });
+});
--- a/examples/whiteboard/README.md
+++ b/examples/whiteboard/README.md
@@ -1,7 +1,7 @@

 # Socket.IO Collaborative Whiteboard

-A simple collaborative whiteboard for socket.io
+A simple collaborative whiteboard for Socket.IO

 ## How to use

--- a/examples/whiteboard/package-lock.json
+++ b/examples/whiteboard/package-lock.json
@@ -13,54 +13,16 @@
        "negotiator": "0.6.2"
      }
    },
-    "after": {
-      "version": "0.8.2",
-      "resolved": "https://registry.npmjs.org/after/-/after-0.8.2.tgz",
-      "integrity": "sha1-/ts5T58OAqqXaOcCvaI7UF+ufh8="
-    },
    "array-flatten": {
      "version": "1.1.1",
      "resolved": "https://registry.npmjs.org/array-flatten/-/array-flatten-1.1.1.tgz",
      "integrity": "sha1-ml9pkFGx5wczKPKgCJaLZOopVdI="
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-    },
-    "yeast": {
-      "version": "0.1.2",
-      "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
-      "integrity": "sha1-AI4G2AlDIMNy28L47XagymyKxBk="
+      "version": "7.4.0",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.4.0.tgz",
+      "integrity": "sha512-kyFwXuV/5ymf+IXhS6f0+eAFvydbaBW3zjpT6hUdAh/hbVjTIB5EHBGi0bPoCLSK2wcuz3BrEkB9LrYv1Nm4NQ=="
    }
  }
 }
--- a/examples/whiteboard/package.json
+++ b/examples/whiteboard/package.json
@@ -9,7 +9,7 @@
  ],
  "dependencies": {
    "express": "~4.17.1",
-    "socket.io": "~2.3.0"
+    "socket.io": "^3.0.0"
  },
  "scripts": {
    "start": "node index"
--- a/lib/client.ts
+++ b/lib/client.ts
@@ -91,9 +91,11 @@ export class Client {
      } else {
        debug("creation of namespace %s was denied", name);
        this._packet({
-          type: PacketType.ERROR,
+          type: PacketType.CONNECT_ERROR,
          nsp: name,
-          data: "Invalid namespace"
+          data: {
+            message: "Invalid namespace"
+          }
        });
      }
    });
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -1,10 +1,13 @@
-import http from "http";
-import { existsSync as exists, readFileSync as read } from "fs";
-import path from "path";
-import engine from "engine.io";
+import http = require("http");
+import { createReadStream } from "fs";
+import { createDeflate, createGzip, createBrotliCompress } from "zlib";
+import accepts = require("accepts");
+import { pipeline } from "stream";
+import path = require("path");
+import engine = require("engine.io");
 import { Client } from "./client";
 import { EventEmitter } from "events";
-import { Namespace } from "./namespace";
+import { ExtendedError, Namespace } from "./namespace";
 import { ParentNamespace } from "./parent-namespace";
 import { Adapter, Room, SocketId } from "socket.io-adapter";
 import * as parser from "socket.io-parser";
@@ -16,14 +19,8 @@ import { CorsOptions } from "cors";

 const debug = debugModule("socket.io:server");

-const clientVersion = require("socket.io-client/package.json").version;
-
-/**
- * Socket.IO client source.
- */
-
-let clientSource = undefined;
-let clientSourceMap = undefined;
+const clientVersion = require("../package.json").version;
+const dotMapRegex = /\.map/;

 type Transport = "polling" | "websocket";

@@ -175,6 +172,7 @@ export class Server extends EventEmitter {
  private eio;
  private engine;
  private _path: string;
+  private clientPathRegex: RegExp;

  /**
   * @private
@@ -220,27 +218,6 @@ export class Server extends EventEmitter {
  public serveClient(v?: boolean): Server | boolean {
    if (!arguments.length) return this._serveClient;
    this._serveClient = v;
-    const resolvePath = function(file) {
-      const filepath = path.resolve(__dirname, "./../../", file);
-      if (exists(filepath)) {
-        return filepath;
-      }
-      return require.resolve(file);
-    };
-    if (v && !clientSource) {
-      clientSource = read(
-        resolvePath("socket.io-client/dist/socket.io.js"),
-        "utf-8"
-      );
-      try {
-        clientSourceMap = read(
-          resolvePath("socket.io-client/dist/socket.io.js.map"),
-          "utf-8"
-        );
-      } catch (err) {
-        debug("could not load sourcemap file");
-      }
-    }
    return this;
  }

@@ -290,7 +267,15 @@ export class Server extends EventEmitter {
  public path(): string;
  public path(v?: string): Server | string {
    if (!arguments.length) return this._path;
+
    this._path = v.replace(/\/$/, "");
+
+    const escapedPath = this._path.replace(/[-\/\\^$*+?.()|[\]{}]/g, "\\$&");
+    this.clientPathRegex = new RegExp(
+      "^" +
+        escapedPath +
+        "/socket\\.io(\\.min|\\.msgpack\\.min)?\\.js(\\.map)?$"
+    );
    return this;
  }

@@ -410,16 +395,12 @@ export class Server extends EventEmitter {
   */
  private attachServe(srv) {
    debug("attaching client serving req handler");
-    const url = this._path + "/socket.io.js";
-    const urlMap = this._path + "/socket.io.js.map";
+
    const evs = srv.listeners("request").slice(0);
-    const self = this;
    srv.removeAllListeners("request");
-    srv.on("request", function(req, res) {
-      if (0 === req.url.indexOf(urlMap)) {
-        self.serveMap(req, res);
-      } else if (0 === req.url.indexOf(url)) {
-        self.serve(req, res);
+    srv.on("request", (req, res) => {
+      if (this.clientPathRegex.test(req.url)) {
+        this.serve(req, res);
      } else {
        for (let i = 0; i < evs.length; i++) {
          evs[i].call(srv, req, res);
@@ -429,13 +410,17 @@ export class Server extends EventEmitter {
  }

  /**
-   * Handles a request serving `/socket.io.js`
+   * Handles a request serving of client source and map
   *
   * @param {http.IncomingMessage} req
   * @param {http.ServerResponse} res
   * @private
   */
  private serve(req: http.IncomingMessage, res: http.ServerResponse) {
+    const filename = req.url.replace(this._path, "");
+    const isMap = dotMapRegex.test(filename);
+    const type = isMap ? "map" : "source";
+
    // Per the standard, ETags must be quoted:
    // https://tools.ietf.org/html/rfc7232#section-2.3
    const expectedEtag = '"' + clientVersion + '"';
@@ -443,48 +428,68 @@ export class Server extends EventEmitter {
    const etag = req.headers["if-none-match"];
    if (etag) {
      if (expectedEtag == etag) {
-        debug("serve client 304");
+        debug("serve client %s 304", type);
        res.writeHead(304);
        res.end();
        return;
      }
    }

-    debug("serve client source");
+    debug("serve client %s", type);
+
    res.setHeader("Cache-Control", "public, max-age=0");
-    res.setHeader("Content-Type", "application/javascript");
+    res.setHeader(
+      "Content-Type",
+      "application/" + (isMap ? "json" : "javascript")
+    );
    res.setHeader("ETag", expectedEtag);
-    res.writeHead(200);
-    res.end(clientSource);
+
+    if (!isMap) {
+      res.setHeader("X-SourceMap", filename.substring(1) + ".map");
+    }
+    Server.sendFile(filename, req, res);
  }

  /**
-   * Handles a request serving `/socket.io.js.map`
-   *
-   * @param {http.IncomingMessage} req
-   * @param {http.ServerResponse} res
+   * @param filename
+   * @param req
+   * @param res
   * @private
   */
-  private serveMap(req: http.IncomingMessage, res: http.ServerResponse) {
-    // Per the standard, ETags must be quoted:
-    // https://tools.ietf.org/html/rfc7232#section-2.3
-    const expectedEtag = '"' + clientVersion + '"';
+  private static sendFile(
+    filename: string,
+    req: http.IncomingMessage,
+    res: http.ServerResponse
+  ) {
+    const readStream = createReadStream(
+      path.join(__dirname, "../client-dist/", filename)
+    );
+    const encoding = accepts(req).encodings(["br", "gzip", "deflate"]);

-    const etag = req.headers["if-none-match"];
-    if (etag) {
-      if (expectedEtag == etag) {
-        debug("serve client 304");
-        res.writeHead(304);
+    const onError = err => {
+      if (err) {
        res.end();
-        return;
      }
-    }
+    };

-    debug("serve client sourcemap");
-    res.setHeader("Content-Type", "application/json");
-    res.setHeader("ETag", expectedEtag);
-    res.writeHead(200);
-    res.end(clientSourceMap);
+    switch (encoding) {
+      case "br":
+        res.writeHead(200, { "content-encoding": "br" });
+        readStream.pipe(createBrotliCompress()).pipe(res);
+        pipeline(readStream, createBrotliCompress(), res, onError);
+        break;
+      case "gzip":
+        res.writeHead(200, { "content-encoding": "gzip" });
+        pipeline(readStream, createGzip(), res, onError);
+        break;
+      case "deflate":
+        res.writeHead(200, { "content-encoding": "deflate" });
+        pipeline(readStream, createDeflate(), res, onError);
+        break;
+      default:
+        res.writeHead(200);
+        pipeline(readStream, res, onError);
+    }
  }

  /**
@@ -588,7 +593,7 @@ export class Server extends EventEmitter {
   * @public
   */
  public use(
-    fn: (socket: Socket, next: (err?: Error) => void) => void
+    fn: (socket: Socket, next: (err?: ExtendedError) => void) => void
  ): Server {
    this.sockets.use(fn);
    return this;
@@ -706,3 +711,5 @@ emitterMethods.forEach(function(fn) {

 module.exports = (srv?, opts?) => new Server(srv, opts);
 module.exports.Server = Server;
+
+export { Socket, ServerOptions, Namespace };
--- a/lib/namespace.ts
+++ b/lib/namespace.ts
@@ -8,6 +8,10 @@ import { Adapter, Room, SocketId } from "socket.io-adapter";

 const debug = debugModule("socket.io:namespace");

+export interface ExtendedError extends Error {
+  data?: any;
+}
+
 export class Namespace extends EventEmitter {
  public readonly name: string;
  public readonly sockets: Map<SocketId, Socket> = new Map();
@@ -18,7 +22,9 @@ export class Namespace extends EventEmitter {
  readonly server: Server;

  /** @private */
-  _fns: Array<(socket: Socket, next: (err: Error) => void) => void> = [];
+  _fns: Array<
+    (socket: Socket, next: (err: ExtendedError) => void) => void
+  > = [];

  /** @private */
  _rooms: Set<Room> = new Set();
@@ -60,7 +66,7 @@ export class Namespace extends EventEmitter {
   * @public
   */
  public use(
-    fn: (socket: Socket, next: (err?: Error) => void) => void
+    fn: (socket: Socket, next: (err?: ExtendedError) => void) => void
  ): Namespace {
    this._fns.push(fn);
    return this;
@@ -73,7 +79,7 @@ export class Namespace extends EventEmitter {
   * @param {Function} fn - last fn call in the middleware
   * @private
   */
-  private run(socket: Socket, fn: (err: Error) => void) {
+  private run(socket: Socket, fn: (err: ExtendedError) => void) {
    const fns = this._fns.slice(0);
    if (!fns.length) return fn(null);

@@ -129,7 +135,11 @@ export class Namespace extends EventEmitter {
    this.run(socket, err => {
      process.nextTick(() => {
        if ("open" == client.conn.readyState) {
-          if (err) return socket._error(err.message);
+          if (err)
+            return socket._error({
+              message: err.message,
+              data: err.data
+            });

          // track socket
          this.sockets.set(socket.id, socket);
@@ -168,11 +178,10 @@ export class Namespace extends EventEmitter {
  /**
   * Emits to all clients.
   *
-   * @return {Namespace} self
+   * @return {Boolean} Always true
   * @public
   */
-  // @ts-ignore
-  public emit(ev: string, ...args: any[]): Namespace {
+  public emit(ev: string, ...args: any[]): boolean {
    if (RESERVED_EVENTS.has(ev)) {
      throw new Error(`"${ev}" is a reserved event name`);
    }
@@ -199,7 +208,7 @@ export class Namespace extends EventEmitter {
      flags: flags
    });

-    return this;
+    return true;
  }

  /**
--- a/lib/parent-namespace.ts
+++ b/lib/parent-namespace.ts
@@ -10,7 +10,7 @@ export class ParentNamespace extends Namespace {

  _initAdapter() {}

-  public emit(...args): Namespace {
+  public emit(...args: any[]): boolean {
    this.children.forEach(nsp => {
      nsp._rooms = this._rooms;
      nsp._flags = this._flags;
@@ -19,7 +19,7 @@ export class ParentNamespace extends Namespace {
    this._rooms.clear();
    this._flags = {};

-    return this;
+    return true;
  }

  createChild(name) {
--- a/lib/socket.ts
+++ b/lib/socket.ts
@@ -1,6 +1,6 @@
 import { EventEmitter } from "events";
 import { PacketType } from "socket.io-parser";
-import url from "url";
+import url = require("url");
 import debugModule from "debug";
 import { Server } from "./index";
 import { Client } from "./client";
@@ -12,8 +12,8 @@ import base64id from "base64id";
 const debug = debugModule("socket.io:socket");

 export const RESERVED_EVENTS = new Set([
-  "error",
  "connect",
+  "connect_error",
  "disconnect",
  "disconnecting",
  // EventEmitter reserved events: https://nodejs.org/api/events.html#events_event_newlistener
@@ -86,6 +86,7 @@ export class Socket extends EventEmitter {
  > = [];
  private flags: BroadcastFlags = {};
  private _rooms: Set<Room> = new Set();
+  private _anyListeners: Array<(...args: any[]) => void>;

  /**
   * Interface to a `Client` for a given `Namespace`.
@@ -128,11 +129,10 @@ export class Socket extends EventEmitter {
  /**
   * Emits to this client.
   *
-   * @return {Socket} self
+   * @return {Boolean} Always true
   * @public
   */
-  // @ts-ignore
-  public emit(ev: string, ...args: any[]) {
+  public emit(ev: string, ...args: any[]): boolean {
    if (RESERVED_EVENTS.has(ev)) {
      throw new Error(`"${ev}" is a reserved event name`);
    }
@@ -170,7 +170,7 @@ export class Socket extends EventEmitter {
      // dispatch packet
      this.packet(packet, flags);
    }
-    return this;
+    return true;
  }

  /**
@@ -238,38 +238,29 @@ export class Socket extends EventEmitter {
   * Joins a room.
   *
   * @param {String|Array} rooms - room or array of rooms
-   * @param {Function} fn - optional, callback
-   * @return {Socket} self
+   * @return a Promise or nothing, depending on the adapter
   * @public
   */
-  public join(rooms: Room | Array<Room>, fn?: (err: Error) => void): Socket {
-    debug("joining room %s", rooms);
+  public join(rooms: Room | Array<Room>): Promise<void> | void {
+    debug("join room %s", rooms);

-    this.adapter.addAll(
+    return this.adapter.addAll(
      this.id,
      new Set(Array.isArray(rooms) ? rooms : [rooms])
    );
-    debug("joined room %s", rooms);
-    fn && fn(null);
-    return this;
  }

  /**
   * Leaves a room.
   *
   * @param {String} room
-   * @param {Function} fn - optional, callback
-   * @return {Socket} self
+   * @return a Promise or nothing, depending on the adapter
   * @public
   */
-  public leave(room: string, fn?: (err: Error) => void): Socket {
+  public leave(room: string): Promise<void> | void {
    debug("leave room %s", room);
-    this.adapter.del(this.id, room);

-    debug("left room %s", room);
-    fn && fn(null);
-
-    return this;
+    return this.adapter.del(this.id, room);
  }

  /**
@@ -324,7 +315,7 @@ export class Socket extends EventEmitter {
        this.ondisconnect();
        break;

-      case PacketType.ERROR:
+      case PacketType.CONNECT_ERROR:
        this._onerror(new Error(packet.data));
    }
  }
@@ -344,7 +335,13 @@ export class Socket extends EventEmitter {
      args.push(this.ack(packet.id));
    }

-    this.dispatch(args);
+    if (this._anyListeners && this._anyListeners.length) {
+      const listeners = this._anyListeners.slice();
+      for (const listener of listeners) {
+        listener.apply(this, args);
+      }
+    }
+    super.emit.apply(this, args);
  }

  /**
@@ -440,7 +437,7 @@ export class Socket extends EventEmitter {
   * @private
   */
  _error(err) {
-    this.packet({ type: PacketType.ERROR, data: err });
+    this.packet({ type: PacketType.CONNECT_ERROR, data: err });
  }

  /**
@@ -510,65 +507,6 @@ export class Socket extends EventEmitter {
    return this;
  }

-  /**
-   * Dispatch incoming event to socket listeners.
-   *
-   * @param {Array} event - event that will get emitted
-   * @private
-   */
-  private dispatch(event: Array<string>): void {
-    debug("dispatching an event %j", event);
-    this.run(event, err => {
-      process.nextTick(() => {
-        if (err) {
-          return this._error(err.message);
-        }
-        super.emit.apply(this, event);
-      });
-    });
-  }
-
-  /**
-   * Sets up socket middleware.
-   *
-   * @param {Function} fn - middleware function (event, next)
-   * @return {Socket} self
-   * @public
-   */
-  public use(
-    fn: (event: Array<any>, next: (err: Error) => void) => void
-  ): Socket {
-    this.fns.push(fn);
-    return this;
-  }
-
-  /**
-   * Executes the middleware for an incoming event.
-   *
-   * @param {Array} event - event that will get emitted
-   * @param {Function} fn - last fn call in the middleware
-   * @private
-   */
-  private run(event: Array<any>, fn: (err: Error) => void) {
-    const fns = this.fns.slice(0);
-    if (!fns.length) return fn(null);
-
-    function run(i) {
-      fns[i](event, function(err) {
-        // upon error, short-circuit
-        if (err) return fn(err);
-
-        // if no middleware left, summon callback
-        if (!fns[i + 1]) return fn(null);
-
-        // go on to next
-        run(i + 1);
-      });
-    }
-
-    run(0);
-  }
-
  /**
   * A reference to the request that originated the underlying Engine.IO Socket.
   *
@@ -593,4 +531,64 @@ export class Socket extends EventEmitter {
  public get rooms(): Set<Room> {
    return this.adapter.socketRooms(this.id) || new Set();
  }
+
+  /**
+   * Adds a listener that will be fired when any event is emitted. The event name is passed as the first argument to the
+   * callback.
+   *
+   * @param listener
+   * @public
+   */
+  public onAny(listener: (...args: any[]) => void): Socket {
+    this._anyListeners = this._anyListeners || [];
+    this._anyListeners.push(listener);
+    return this;
+  }
+
+  /**
+   * Adds a listener that will be fired when any event is emitted. The event name is passed as the first argument to the
+   * callback. The listener is added to the beginning of the listeners array.
+   *
+   * @param listener
+   * @public
+   */
+  public prependAny(listener: (...args: any[]) => void): Socket {
+    this._anyListeners = this._anyListeners || [];
+    this._anyListeners.unshift(listener);
+    return this;
+  }
+
+  /**
+   * Removes the listener that will be fired when any event is emitted.
+   *
+   * @param listener
+   * @public
+   */
+  public offAny(listener?: (...args: any[]) => void): Socket {
+    if (!this._anyListeners) {
+      return this;
+    }
+    if (listener) {
+      const listeners = this._anyListeners;
+      for (let i = 0; i < listeners.length; i++) {
+        if (listener === listeners[i]) {
+          listeners.splice(i, 1);
+          return this;
+        }
+      }
+    } else {
+      this._anyListeners = [];
+    }
+    return this;
+  }
+
+  /**
+   * Returns an array of listeners that are listening for any event that is specified. This array can be manipulated,
+   * e.g. to remove listeners.
+   *
+   * @public
+   */
+  public listenersAny() {
+    return this._anyListeners || [];
+  }
 }
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
  "name": "socket.io",
-  "version": "3.0.0-rc2",
+  "version": "3.0.1",
  "description": "node.js realtime framework server",
  "keywords": [
    "realtime",
@@ -13,6 +13,7 @@
  ],
  "files": [
    "dist/",
+    "client-dist/",
    "wrapper.mjs"
  ],
  "type": "commonjs",
@@ -34,12 +35,12 @@
    "prepack": "tsc"
  },
  "dependencies": {
+    "accepts": "~1.3.4",
    "base64id": "~2.0.0",
    "debug": "~4.1.0",
    "engine.io": "~4.0.0",
-    "socket.io-adapter": "2.0.3-rc1",
-    "socket.io-client": "3.0.0-rc2",
-    "socket.io-parser": "4.0.1-rc2"
+    "socket.io-adapter": "~2.0.3",
+    "socket.io-parser": "~4.0.1"
  },
  "devDependencies": {
    "@types/cookie": "^0.4.0",
@@ -53,6 +54,7 @@
    "mocha": "^3.5.3",
    "nyc": "^11.2.1",
    "prettier": "^1.19.1",
+    "socket.io-client": "3.0.0",
    "superagent": "^3.8.2",
    "supertest": "^3.0.0",
    "ts-node": "^9.0.0",
--- a/test/socket.io.ts
+++ b/test/socket.io.ts
@@ -1,6 +1,6 @@
 "use strict";

-import { Server } from "..";
+import { Server, Socket } from "..";
 import { createServer } from "http";
 import fs = require("fs");
 import { join } from "path";
@@ -35,23 +35,73 @@ describe("socket.io", () => {
    describe("http.Server", () => {
      const clientVersion = require("socket.io-client/package.json").version;

-      it("should serve static files", done => {
+      const testSource = filename => done => {
        const srv = createServer();
        new Server(srv);
        request(srv)
-          .get("/socket.io/socket.io.js")
+          .get("/socket.io/" + filename)
          .buffer(true)
          .end((err, res) => {
            if (err) return done(err);
-            const ctype = res.headers["content-type"];
-            expect(ctype).to.be("application/javascript");
+            expect(res.headers["content-type"]).to.be("application/javascript");
+            expect(res.headers.etag).to.be('"' + clientVersion + '"');
+            expect(res.headers["x-sourcemap"]).to.be(filename + ".map");
+            expect(res.text).to.match(/engine\.io/);
+            expect(res.status).to.be(200);
+            done();
+          });
+      };
+
+      const testSourceMap = filename => done => {
+        const srv = createServer();
+        new Server(srv);
+        request(srv)
+          .get("/socket.io/" + filename)
+          .buffer(true)
+          .end((err, res) => {
+            if (err) return done(err);
+            expect(res.headers["content-type"]).to.be("application/json");
            expect(res.headers.etag).to.be('"' + clientVersion + '"');
            expect(res.text).to.match(/engine\.io/);
            expect(res.status).to.be(200);
            done();
          });
+      };
+
+      it("should serve client", testSource("socket.io.js"));
+      it("should serve source map", testSourceMap("socket.io.js.map"));
+      it("should serve client (min)", testSource("socket.io.min.js"));
+
+      it(
+        "should serve source map (min)",
+        testSourceMap("socket.io.min.js.map")
+      );
+
+      it("should serve client (gzip)", done => {
+        const srv = createServer();
+        new Server(srv);
+        request(srv)
+          .get("/socket.io/socket.io.js")
+          .set("accept-encoding", "gzip,br,deflate")
+          .buffer(true)
+          .end((err, res) => {
+            if (err) return done(err);
+            expect(res.headers["content-encoding"]).to.be("gzip");
+            expect(res.status).to.be(200);
+            done();
+          });
      });

+      it(
+        "should serve bundle with msgpack parser",
+        testSource("socket.io.msgpack.min.js")
+      );
+
+      it(
+        "should serve source map for bundle with msgpack parser",
+        testSourceMap("socket.io.msgpack.min.js.map")
+      );
+
      it("should handle 304", done => {
        const srv = createServer();
        new Server(srv);
@@ -317,7 +367,7 @@ describe("socket.io", () => {
      const sio = new Server(srv);
      srv.listen(() => {
        const socket = client(srv);
-        sio.on("connection", socket => {
+        sio.on("connection", (socket: Socket) => {
          expect(socket).to.be.a(Socket);
          done();
        });
@@ -448,10 +498,9 @@ describe("socket.io", () => {
        const socket = client(srv);

        sio.on("connection", s => {
-          s.join("a", () => {
-            // FIXME not sure why process.nextTick() is needed here
-            process.nextTick(() => s.disconnect());
-          });
+          s.join("a");
+          // FIXME not sure why process.nextTick() is needed here
+          process.nextTick(() => s.disconnect());

          let total = 2;
          s.on("disconnecting", reason => {
@@ -472,8 +521,8 @@ describe("socket.io", () => {
      const sio = new Server(srv);
      srv.listen(() => {
        const socket = client(srv, "/doesnotexist");
-        socket.on("error", err => {
-          expect(err).to.be("Invalid namespace");
+        socket.on("connect_error", err => {
+          expect(err.message).to.be("Invalid namespace");
          done();
        });
      });
@@ -538,22 +587,19 @@ describe("socket.io", () => {
        let total = 3;
        sio.of("/chat").on("connection", socket => {
          if (chatIndex++) {
-            socket.join("foo", () => {
-              chatFooSid = socket.id;
-              --total || getSockets();
-            });
+            socket.join("foo");
+            chatFooSid = socket.id;
+            --total || getSockets();
          } else {
-            socket.join("bar", () => {
-              chatBarSid = socket.id;
-              --total || getSockets();
-            });
+            socket.join("bar");
+            chatBarSid = socket.id;
+            --total || getSockets();
          }
        });
        sio.of("/other").on("connection", socket => {
-          socket.join("foo", () => {
-            otherSid = socket.id;
-            --total || getSockets();
-          });
+          socket.join("foo");
+          otherSid = socket.id;
+          --total || getSockets();
        });
      });
      async function getSockets() {
@@ -583,22 +629,19 @@ describe("socket.io", () => {
        let total = 3;
        sio.of("/chat").on("connection", socket => {
          if (chatIndex++) {
-            socket.join("foo", () => {
-              chatFooSid = socket.id;
-              --total || getSockets();
-            });
+            socket.join("foo");
+            chatFooSid = socket.id;
+            --total || getSockets();
          } else {
-            socket.join("bar", () => {
-              chatBarSid = socket.id;
-              --total || getSockets();
-            });
+            socket.join("bar");
+            chatBarSid = socket.id;
+            --total || getSockets();
          }
        });
        sio.of("/other").on("connection", socket => {
-          socket.join("foo", () => {
-            otherSid = socket.id;
-            --total || getSockets();
-          });
+          socket.join("foo");
+          otherSid = socket.id;
+          --total || getSockets();
        });
      });
      async function getSockets() {
@@ -738,7 +781,7 @@ describe("socket.io", () => {
              next();
              if (++count === 4) done();
            });
-          socket.on("error", err => {
+          socket.on("connect_error", err => {
            expect().fail();
          });
          socket.on("connect", () => {
@@ -770,8 +813,8 @@ describe("socket.io", () => {
          const socket = client(srv, "/abc");
          sio.of(/^\/dynamic-\d+$/);
          sio.of((name, query, next) => next(null, "/dynamic-101" === name));
-          socket.on("error", err => {
-            expect(err).to.be("Invalid namespace");
+          socket.on("connect_error", err => {
+            expect(err.message).to.be("Invalid namespace");
            done();
          });
        });
@@ -1671,20 +1714,6 @@ describe("socket.io", () => {
      });
    });

-    it("should always trigger the callback (if provided) when joining a room", done => {
-      const srv = createServer();
-      const sio = new Server(srv);
-
-      srv.listen(() => {
-        const socket = client(srv);
-        sio.on("connection", s => {
-          s.join("a", () => {
-            s.join("a", done);
-          });
-        });
-      });
-    });
-
    it("should throw on reserved event", done => {
      const srv = createServer();
      const sio = new Server(srv);
@@ -1692,14 +1721,86 @@ describe("socket.io", () => {
      srv.listen(() => {
        const socket = client(srv);
        sio.on("connection", s => {
-          expect(() => s.emit("error")).to.throwException(
-            /"error" is a reserved event name/
+          expect(() => s.emit("connect_error")).to.throwException(
+            /"connect_error" is a reserved event name/
          );
          socket.close();
          done();
        });
      });
    });
+
+    describe("onAny", () => {
+      it("should call listener", done => {
+        const srv = createServer();
+        const sio = new Server(srv);
+
+        srv.listen(() => {
+          const socket = client(srv, { multiplex: false });
+
+          socket.emit("my-event", "123");
+
+          sio.on("connection", (socket: Socket) => {
+            socket.onAny((event, arg1) => {
+              expect(event).to.be("my-event");
+              expect(arg1).to.be("123");
+              done();
+            });
+          });
+        });
+      });
+
+      it("should prepend listener", done => {
+        const srv = createServer();
+        const sio = new Server(srv);
+
+        srv.listen(() => {
+          const socket = client(srv, { multiplex: false });
+
+          socket.emit("my-event", "123");
+
+          sio.on("connection", (socket: Socket) => {
+            let count = 0;
+
+            socket.onAny((event, arg1) => {
+              expect(count).to.be(2);
+              done();
+            });
+
+            socket.prependAny(() => {
+              expect(count++).to.be(1);
+            });
+
+            socket.prependAny(() => {
+              expect(count++).to.be(0);
+            });
+          });
+        });
+      });
+
+      it("should remove listener", done => {
+        const srv = createServer();
+        const sio = new Server(srv);
+
+        srv.listen(() => {
+          const socket = client(srv, { multiplex: false });
+
+          socket.emit("my-event", "123");
+
+          sio.on("connection", (socket: Socket) => {
+            const fail = () => done(new Error("fail"));
+
+            socket.onAny(fail);
+            socket.offAny(fail);
+            expect(socket.listenersAny.length).to.be(0);
+
+            socket.onAny(() => {
+              done();
+            });
+          });
+        });
+      });
+    });
  });

  describe("messaging many", () => {
@@ -1821,13 +1922,13 @@ describe("socket.io", () => {
        socket1.on("a", () => {
          done();
        });
-        socket1.emit("join", "woot", () => {
-          socket1.emit("emit", "woot");
-        });
+        socket1.emit("join", "woot");
+        socket1.emit("emit", "woot");

        sio.on("connection", socket => {
          socket.on("join", (room, fn) => {
-            socket.join(room, fn);
+            socket.join(room);
+            fn && fn();
          });

          socket.on("emit", room => {
@@ -1864,7 +1965,8 @@ describe("socket.io", () => {

        sio.on("connection", socket => {
          socket.on("join", (room, fn) => {
-            socket.join(room, fn);
+            socket.join(room);
+            fn && fn();
          });

          socket.on("emit", room => {
@@ -1909,7 +2011,8 @@ describe("socket.io", () => {

        sio.on("connection", socket => {
          socket.on("join", (room, fn) => {
-            socket.join(room, fn);
+            socket.join(room);
+            fn && fn();
          });

          socket.on("broadcast", () => {
@@ -1956,7 +2059,8 @@ describe("socket.io", () => {

        sio.on("connection", socket => {
          socket.on("join", (room, fn) => {
-            socket.join(room, fn);
+            socket.join(room);
+            fn && fn();
          });
          socket.on("broadcast", () => {
            socket.broadcast.to("test").emit("bin", Buffer.alloc(5));
@@ -1973,21 +2077,17 @@ describe("socket.io", () => {
      srv.listen(() => {
        const socket = client(srv);
        sio.on("connection", s => {
-          s.join("a", () => {
-            expect(s.rooms).to.contain(s.id, "a");
-            s.join("b", () => {
-              expect(s.rooms).to.contain(s.id, "a", "b");
-              s.join("c", () => {
-                expect(s.rooms).to.contain(s.id, "a", "b", "c");
-                s.leave("b", () => {
-                  expect(s.rooms).to.contain(s.id, "a", "c");
-                  s.leaveAll();
-                  expect(s.rooms.size).to.eql(0);
-                  done();
-                });
-              });
-            });
-          });
+          s.join("a");
+          expect(s.rooms).to.contain(s.id, "a");
+          s.join("b");
+          expect(s.rooms).to.contain(s.id, "a", "b");
+          s.join("c");
+          expect(s.rooms).to.contain(s.id, "a", "b", "c");
+          s.leave("b");
+          expect(s.rooms).to.contain(s.id, "a", "c");
+          s.leaveAll();
+          expect(s.rooms.size).to.eql(0);
+          done();
        });
      });
    });
@@ -1999,13 +2099,11 @@ describe("socket.io", () => {
      srv.listen(() => {
        const socket = client(srv);
        sio.on("connection", s => {
-          s.join("a", () => {
-            expect(s.nsp.adapter.rooms).to.contain("a");
-            s.leave("a", () => {
-              expect(s.nsp.adapter.rooms).to.not.contain("a");
-              done();
-            });
-          });
+          s.join("a");
+          expect(s.nsp.adapter.rooms).to.contain("a");
+          s.leave("a");
+          expect(s.nsp.adapter.rooms).to.not.contain("a");
+          done();
        });
      });
    });
@@ -2017,18 +2115,15 @@ describe("socket.io", () => {
      srv.listen(() => {
        const socket = client(srv);
        sio.on("connection", s => {
-          s.join("a", () => {
-            expect(s.rooms).to.contain(s.id, "a");
-            s.join("b", () => {
-              expect(s.rooms).to.contain(s.id, "a", "b");
-              s.leave("unknown", () => {
-                expect(s.rooms).to.contain(s.id, "a", "b");
-                s.leaveAll();
-                expect(s.rooms.size).to.eql(0);
-                done();
-              });
-            });
-          });
+          s.join("a");
+          expect(s.rooms).to.contain(s.id, "a");
+          s.join("b");
+          expect(s.rooms).to.contain(s.id, "a", "b");
+          s.leave("unknown");
+          expect(s.rooms).to.contain(s.id, "a", "b");
+          s.leaveAll();
+          expect(s.rooms.size).to.eql(0);
+          done();
        });
      });
    });
@@ -2040,10 +2135,9 @@ describe("socket.io", () => {
      srv.listen(() => {
        const socket = client(srv);
        sio.on("connection", s => {
-          s.join(["a", "b", "c"], () => {
-            expect(s.rooms).to.contain(s.id, "a", "b", "c");
-            done();
-          });
+          s.join(["a", "b", "c"]);
+          expect(s.rooms).to.contain(s.id, "a", "b", "c");
+          done();
        });
      });
    });
@@ -2090,8 +2184,31 @@ describe("socket.io", () => {
        socket.on("connect", () => {
          done(new Error("nope"));
        });
-        socket.on("error", err => {
-          expect(err).to.be("Authentication error");
+        socket.on("connect_error", err => {
+          expect(err.message).to.be("Authentication error");
+          done();
+        });
+      });
+    });
+
+    it("should pass an object", done => {
+      const srv = createServer();
+      const sio = new Server(srv);
+      sio.use((socket, next) => {
+        const err = new Error("Authentication error");
+        // @ts-ignore
+        err.data = { a: "b", c: 3 };
+        next(err);
+      });
+      srv.listen(() => {
+        const socket = client(srv);
+        socket.on("connect", () => {
+          done(new Error("nope"));
+        });
+        socket.on("connect_error", err => {
+          expect(err).to.be.an(Error);
+          expect(err.message).to.eql("Authentication error");
+          expect(err.data).to.eql({ a: "b", c: 3 });
          done();
        });
      });
@@ -2214,69 +2331,4 @@ describe("socket.io", () => {
      });
    });
  });
-
-  describe("socket middleware", () => {
-    const { Socket } = require("../dist/socket");
-
-    it("should call functions", done => {
-      const srv = createServer();
-      const sio = new Server(srv);
-      let run = 0;
-
-      srv.listen(() => {
-        const socket = client(srv, { multiplex: false });
-
-        socket.emit("join", "woot");
-
-        sio.on("connection", socket => {
-          socket.use((event, next) => {
-            expect(event).to.eql(["join", "woot"]);
-            event.unshift("wrap");
-            run++;
-            next();
-          });
-          socket.use((event, next) => {
-            expect(event).to.eql(["wrap", "join", "woot"]);
-            run++;
-            next();
-          });
-          socket.on("wrap", (data1, data2) => {
-            expect(data1).to.be("join");
-            expect(data2).to.be("woot");
-            expect(run).to.be(2);
-            done();
-          });
-        });
-      });
-    });
-
-    it("should pass errors", done => {
-      const srv = createServer();
-      const sio = new Server(srv);
-
-      srv.listen(() => {
-        const clientSocket = client(srv, { multiplex: false });
-
-        clientSocket.emit("join", "woot");
-
-        clientSocket.on("error", err => {
-          expect(err).to.be("Authentication error");
-          done();
-        });
-
-        sio.on("connection", socket => {
-          socket.use((event, next) => {
-            next(new Error("Authentication error"));
-          });
-          socket.use((event, next) => {
-            done(new Error("nope"));
-          });
-
-          socket.on("join", () => {
-            done(new Error("nope"));
-          });
-        });
-      });
-    });
-  });
 });
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,7 +1,6 @@
 {
  "compilerOptions": {
    "outDir": "./dist",
-    "allowJs": true,
    "target": "es2017",
    "module": "commonjs",
    "declaration": true,
Author	SHA1	Message	Date
Damien Arrachequesne	0317a077be	chore(release): 3.0.1 Diff: https://github.com/socketio/socket.io/compare/3.0.0...3.0.1	2020-11-09 10:27:58 +01:00
Damien Arrachequesne	d00c0c0d9d	docs(examples): update examples to Socket.IO v3 Other examples need some additional work (Redis adapter migration, ...).	2020-11-09 10:19:40 +01:00
Avi Vahl	f62f180eda	fix: export ServerOptions and Namespace types (#3684 ) @types/socket.io used to export these.	2020-11-09 08:58:14 +01:00
Damien Arrachequesne	50671d984a	fix(typings): update the signature of the emit method The previous signature was not compatible with EventEmitter.emit(). The typescript compilation threw: ``` node_modules/socket.io/dist/namespace.d.ts(89,5): error TS2416: Property 'emit' in type 'Namespace' is not assignable to the same property in base type 'EventEmitter'. Type '(ev: string, ...args: any[]) => Namespace' is not assignable to type '(event: string \| symbol, ...args: any[]) => boolean'. Type 'Namespace' is not assignable to type 'boolean'. node_modules/socket.io/dist/socket.d.ts(84,5): error TS2416: Property 'emit' in type 'Socket' is not assignable to the same property in base type 'EventEmitter'. Type '(ev: string, ...args: any[]) => this' is not assignable to type '(event: string \| symbol, ...args: any[]) => boolean'. Type 'this' is not assignable to type 'boolean'. Type 'Socket' is not assignable to type 'boolean'. ``` Note: the emit calls cannot be chained anymore: ```js socket.emit("hello").emit("world"); // will not work anymore ```	2020-11-08 00:07:56 +01:00
Damien Arrachequesne	8a69f15437	chore: restore package-lock.json file	2020-11-05 22:25:35 +01:00
Damien Arrachequesne	1af3267e3f	chore(release): 3.0.0 Diff: https://github.com/socketio/socket.io/compare/2.3.0...3.0.0	2020-11-05 22:07:47 +01:00
Damien Arrachequesne	02951c4391	chore(release): 3.0.0-rc4 Diff: https://github.com/socketio/socket.io/compare/3.0.0-rc3...3.0.0-rc4	2020-10-30 23:02:43 +01:00
Damien Arrachequesne	54bf4a44e9	feat: emit an Error object upon middleware error This commit restores the ability to send additional data in the middleware functions, which was removed during the rewrite to Typescript ([1]). The only difference with the previous implementation is that the client will now emit a "connect_error" (previously, "error") event with an actual Error object, with both the message and an optional "data" attribute. ```js // server-side io.use((socket, next) => { const err = new Error("not authorized"); err.data = { content: "Please retry later" }; next(err); }); // client-side socket.on("connect_error", err => { console.log(err.message); // not authorized console.log(err.data.content); // Please retry later }); ``` [1]: `a5581a9789`	2020-10-30 22:52:08 +01:00
Damien Arrachequesne	aa7574f884	feat: serve msgpack bundle See `71d60480af`	2020-10-27 23:17:12 +01:00
Damien Arrachequesne	64056d6616	docs(examples): update TypeScript example	2020-10-27 22:18:07 +01:00
Damien Arrachequesne	cacad7029a	chore(release): 3.0.0-rc3 Diff: https://github.com/socketio/socket.io/compare/3.0.0-rc2...3.0.0-rc3	2020-10-27 00:44:30 +01:00
Damien Arrachequesne	d16c035d25	refactor: rename ERROR to CONNECT_ERROR The meaning is not modified: this packet type is still used by the server when the connection to a namespace is refused.	2020-10-26 00:29:11 +01:00
Damien Arrachequesne	5c73733985	feat: add support for catch-all listeners Inspired from EventEmitter2 [1] ```js io.on("connect", socket => { socket.onAny((event, ...args) => {}); socket.prependAny((event, ...args) => {}); socket.offAny(); // remove all listeners socket.offAny(listener); const listeners = socket.listenersAny(); }); ``` Breaking change: the socket.use() method is removed This method was introduced in [2] for the same feature (having a catch-all listener), but there were two issues: - the API is not very user-friendly, since the user has to know the structure of the packet argument - it uses an ERROR packet, which is reserved for Namespace authentication issues (see [3]) [1]: https://github.com/EventEmitter2/EventEmitter2 [2]: https://github.com/socketio/socket.io/issues/434 [3]: https://github.com/socketio/socket.io-protocol	2020-10-25 23:44:01 +01:00
Damien Arrachequesne	129c6417bd	feat: make Socket#join() and Socket#leave() synchronous Depending on the adapter, Socket#join() may return: - nothing (in-memory and Redis adapters) - a promise (custom adapters) Breaking change: Socket#join() and Socket#leave() do not accept a callback argument anymore. Before: ```js socket.join("room1", () => { io.to("room1").emit("hello"); }); ``` After: ``` socket.join("room1"); io.to("room1").emit("hello"); // or await socket.join("room1"); for custom adapters ``` Note: the need for an asynchronous method came from the Redis adapter, which did override the Adapter#add() method in earlier versions, but this is not the case anymore. Reference: - https://github.com/socketio/socket.io/blob/2.3.0/lib/socket.js#L236-L258 - https://github.com/socketio/socket.io-adapter/blob/1.1.2/index.js#L56-L65 - `05f926e13e` Related: https://github.com/socketio/socket.io/issues/3662	2020-10-22 01:50:13 +02:00
Damien Arrachequesne	0d74f290cd	refactor(typings): export Socket class In order to be able to cast it on the argument of the "connect" event: ```js import { Socket } from "socket.io"; io.on("connect", (socket: Socket) => { // ... }); ```	2020-10-17 03:36:15 +02:00
Damien Arrachequesne	7603da71a5	feat: remove prod dependency to socket.io-client The client bundles are included in the repository in order to remove socket.io-client from the list of production dependencies and thus to reduce the total number of dependencies when installing the server. This means the release of the client and the server must now be in sync (which is almost always the case actually). The minified build is now served: - /<path>/socket.io.js - /<path>/socket.io.js.map - /<path>/socket.io.min.js - /<path>/socket.io.min.js.map The content will now be compressed as well.	2020-10-17 02:11:15 +02:00
Damien Arrachequesne	a81b9f31cf	docs(examples): add example with TypeScript There are two issues with the typings: - on the client-side, the Emitter class is not properly imported (hence the @ts-ignore) - on the server-side, the Socket class is not exported (in order to cast it in the "connect" event)	2020-10-15 13:38:46 +02:00
Damien Arrachequesne	20ea6bd277	docs(examples): add example with ES modules	2020-10-15 13:26:55 +02:00