refactor: use ES6 Maps instead of plain objects

These attributes were not part of the public API, so there's no
breaking change.

Author: darrachequesne

lib/client.ts

@@ -4,6 +4,7 @@ import debugModule = require("debug");
 import { IncomingMessage } from "http";
 import { Server } from "./index";
 import { Socket } from "./socket";
+import { SocketId } from "socket.io-adapter";
 
 const debug = debugModule("socket.io:client");
 
@@ -15,8 +16,8 @@ export class Client {
   private readonly server;
   private readonly encoder;
   private readonly decoder;
-  private sockets: object = {};
-  private nsps: object = {};
+  private sockets: Map<SocketId, Socket> = new Map();
+  private nsps: Map<string, Socket> = new Map();
   private connectBuffer: Array<string> = [];
 
   /**
@@ -65,7 +66,7 @@ export class Client {
    * @package
    */
   public connect(name, query = {}) {
-    if (this.server.nsps[name]) {
+    if (this.server.nsps.has(name)) {
       debug("connecting to namespace %s", name);
       return this.doConnect(name, query);
     }
@@ -94,19 +95,18 @@ export class Client {
   private doConnect(name, query) {
     const nsp = this.server.of(name);
 
-    if ("/" != name && !this.nsps["/"]) {
+    if ("/" != name && !this.nsps.has("/")) {
       this.connectBuffer.push(name);
       return;
     }
 
-    const self = this;
-    const socket = nsp.add(this, query, function() {
-      self.sockets[socket.id] = socket;
-      self.nsps[nsp.name] = socket;
+    const socket = nsp.add(this, query, () => {
+      this.sockets.set(socket.id, socket);
+      this.nsps.set(nsp.name, socket);
 
-      if ("/" == nsp.name && self.connectBuffer.length > 0) {
-        self.connectBuffer.forEach(self.connect, self);
-        self.connectBuffer = [];
+      if ("/" == nsp.name && this.connectBuffer.length > 0) {
+        this.connectBuffer.forEach(this.connect, this);
+        this.connectBuffer = [];
       }
     });
   }
@@ -117,12 +117,10 @@ export class Client {
    * @package
    */
   public disconnect() {
-    for (const id in this.sockets) {
-      if (this.sockets.hasOwnProperty(id)) {
-        this.sockets[id].disconnect();
-      }
+    for (const socket of this.sockets.values()) {
+      socket.disconnect();
     }
-    this.sockets = {};
+    this.sockets.clear();
     this.close();
   }
 
@@ -132,10 +130,10 @@ export class Client {
    * @package
    */
   public remove(socket: Socket) {
-    if (this.sockets.hasOwnProperty(socket.id)) {
-      const nsp = this.sockets[socket.id].nsp.name;
-      delete this.sockets[socket.id];
-      delete this.nsps[nsp];
+    if (this.sockets.has(socket.id)) {
+      const nsp = this.sockets.get(socket.id).nsp.name;
+      this.sockets.delete(socket.id);
+      this.nsps.delete(nsp);
     } else {
       debug("ignoring remove for %s", socket.id);
     }
@@ -207,7 +205,7 @@ export class Client {
         url.parse(packet.nsp, true).query
       );
     } else {
-      const socket = this.nsps[packet.nsp];
+      const socket = this.nsps.get(packet.nsp);
       if (socket) {
         process.nextTick(function() {
           socket.onpacket(packet);
@@ -224,10 +222,8 @@ export class Client {
    * @param {Object} err object
    */
   private onerror(err) {
-    for (const id in this.sockets) {
-      if (this.sockets.hasOwnProperty(id)) {
-        this.sockets[id].onerror(err);
-      }
+    for (const socket of this.sockets.values()) {
+      socket.onerror(err);
     }
     this.conn.close();
   }
@@ -244,12 +240,10 @@ export class Client {
     this.destroy();
 
     // `nsps` and `sockets` are cleaned up seamlessly
-    for (const id in this.sockets) {
-      if (this.sockets.hasOwnProperty(id)) {
-        this.sockets[id].onclose(reason);
-      }
+    for (const socket of this.sockets.values()) {
+      socket.onclose(reason);
     }
-    this.sockets = {};
+    this.sockets.clear();
 
     this.decoder.destroy(); // clean up decoder
   }

lib/index.ts

@@ -31,7 +31,7 @@ class Server extends EventEmitter {
   /** @package */
   public readonly encoder;
 
-  private nsps: object = {};
+  private nsps: Map<string, Namespace> = new Map();
   private parentNsps: Map<
     | string
     | RegExp
@@ -224,10 +224,8 @@ class Server extends EventEmitter {
   public adapter(v) {
     if (!arguments.length) return this._adapter;
     this._adapter = v;
-    for (const i in this.nsps) {
-      if (this.nsps.hasOwnProperty(i)) {
-        this.nsps[i].initAdapter();
-      }
+    for (const nsp of this.nsps.values()) {
+      nsp.initAdapter();
     }
     return this;
   }
@@ -507,11 +505,11 @@ class Server extends EventEmitter {
 
     if (String(name)[0] !== "/") name = "/" + name;
 
-    let nsp = this.nsps[name];
+    let nsp = this.nsps.get(name);
     if (!nsp) {
       debug("initializing namespace %s", name);
       nsp = new Namespace(this, name);
-      this.nsps[name] = nsp;
+      this.nsps.set(name, nsp);
     }
     if (fn) nsp.on("connect", fn);
     return nsp;
@@ -523,10 +521,8 @@ class Server extends EventEmitter {
    * @param {Function} [fn] optional, called as `fn([err])` on error OR all conns closed
    */
   public close(fn: (err?: Error) => void): void {
-    for (const id in this.nsps["/"].sockets) {
-      if (this.nsps["/"].sockets.hasOwnProperty(id)) {
-        this.nsps["/"].sockets[id].onclose();
-      }
+    for (const socket of this.sockets.sockets.values()) {
+      socket.onclose("server shutting down");
     }
 
     this.engine.close();

lib/namespace.ts

@@ -35,8 +35,8 @@ export class Namespace extends EventEmitter {
   public flags: any = {};
   /** @package */
   public ids: number = 0;
-
-  private readonly sockets: object = {};
+  /** @package */
+  public sockets: Map<SocketId, Socket> = new Map();
 
   /**
    * Namespace constructor.
@@ -55,8 +55,10 @@ export class Namespace extends EventEmitter {
    * Initializes the `Adapter` for this nsp.
    * Run upon changing adapter by `Server#adapter`
    * in addition to the constructor.
+   *
+   * @package
    */
-  private initAdapter(): void {
+  public initAdapter(): void {
     this.adapter = new (this.server.adapter())(this);
   }
 
@@ -132,14 +134,13 @@ export class Namespace extends EventEmitter {
   private add(client: Client, query, fn?: () => void): Socket {
     debug("adding socket to nsp %s", this.name);
     const socket = new Socket(this, client, query);
-    const self = this;
     this.run(socket, err => {
       process.nextTick(() => {
         if ("open" == client.conn.readyState) {
           if (err) return socket.error(err.message);
 
           // track socket
-          self.sockets[socket.id] = socket;
+          this.sockets.set(socket.id, socket);
 
           // it's paramount that the internal `onconnect` logic
           // fires before user-set events to prevent state order
@@ -165,8 +166,8 @@ export class Namespace extends EventEmitter {
    * @package
    */
   public remove(socket: Socket): void {
-    if (this.sockets.hasOwnProperty(socket.id)) {
-      delete this.sockets[socket.id];
+    if (this.sockets.has(socket.id)) {
+      this.sockets.delete(socket.id);
     } else {
       debug("ignoring remove for %s", socket.id);
     }

lib/parent-namespace.ts

@@ -10,15 +10,16 @@ export class ParentNamespace extends Namespace {
 
   initAdapter() {}
 
-  // @ts-ignore
-  public emit(...args) {
+  public emit(...args): Namespace {
     this.children.forEach(nsp => {
       nsp.rooms = this.rooms;
       nsp.flags = this.flags;
       nsp.emit.apply(nsp, args);
     });
     this.rooms.clear();
     this.flags = {};
+
+    return this;
   }
 
   createChild(name) {
@@ -33,7 +34,7 @@ export class ParentNamespace extends Namespace {
       namespace.on("connection", listener)
     );
     this.children.add(namespace);
-    this.server.nsps[name] = namespace;
+    this.server.nsps.set(name, namespace);
     return namespace;
   }
 }

lib/socket.ts

@@ -76,7 +76,7 @@ export class Socket extends EventEmitter {
 
   private readonly server: Server;
   private readonly adapter: Adapter;
-  private acks: object = {};
+  private acks: Map<number, () => void> = new Map();
   private fns: Array<
     (event: Array<any>, next: (err: Error) => void) => void
   > = [];
@@ -154,7 +154,7 @@ export class Socket extends EventEmitter {
       }
 
       debug("emitting packet with ack id %d", this.nsp.ids);
-      this.acks[this.nsp.ids] = args.pop();
+      this.acks.set(this.nsp.ids, args.pop());
       packet.id = this.nsp.ids++;
     }
 
@@ -376,11 +376,11 @@ export class Socket extends EventEmitter {
    * Called upon ack packet.
    */
   private onack(packet): void {
-    const ack = this.acks[packet.id];
+    const ack = this.acks.get(packet.id);
     if ("function" == typeof ack) {
       debug("calling ack %s with %j", packet.id, packet.data);
       ack.apply(this, packet.data);
-      delete this.acks[packet.id];
+      this.acks.delete(packet.id);
     } else {
       debug("bad ack %s", packet.id);
     }
@@ -396,8 +396,10 @@ export class Socket extends EventEmitter {
 
   /**
    * Handles a client error.
+   *
+   * @package
    */
-  private onerror(err): void {
+  public onerror(err): void {
     if (this.listeners("error").length) {
       super.emit("error", err);
     } else {
@@ -411,8 +413,10 @@ export class Socket extends EventEmitter {
    *
    * @param {String} reason
    * @throw {Error} optional error object
+   *
+   * @package
    */
-  private onclose(reason: string) {
+  public onclose(reason: string) {
     if (!this.connected) return this;
     debug("closing socket - reason %s", reason);
     super.emit("disconnecting", reason);