From 00ce8f1016d73c9d76bc867cc8ad6a6f4b5a725b Mon Sep 17 00:00:00 2001
From: Tobias Berger <tobi.berger13@gmail.com>
Date: Sat, 8 Jan 2022 20:23:03 +0100
Subject: [PATCH] Begin tracking active connections

---
 server.node.ts | 53 +++++++++++++++++++++++++-------------------------
 1 file changed, 27 insertions(+), 26 deletions(-)

diff --git a/server.node.ts b/server.node.ts
index 1bac80f..e146a57 100644
--- a/server.node.ts
+++ b/server.node.ts
@@ -4,7 +4,11 @@ import { WebSocketServer } from "ws";
 
 import * as crypto from "crypto";
 
-import type { AckMessage, TextMessage } from "./lib/ServerMessage";
+import type {
+  AckMessage,
+  IdResponseMessage,
+  TextMessage,
+} from "./lib/ServerMessage";
 
 import {
   isServerMessage,
@@ -41,7 +45,14 @@ async function handleTextMessage(message: TextMessage, from: string) {
   }
 }
 
-webSocketServer.on("connection", function connection(socket, request) {
+async function handleCloseConnection(id: string) {
+  activeConnections.delete(id);
+}
+
+const activeConnections = new Set<string>();
+let nextId = 0;
+
+webSocketServer.on("connection", function connection(socket) {
   const close = (reason: string, code: number = 1000) => {
     socket.send(
       JSON.stringify({
@@ -51,36 +62,24 @@ webSocketServer.on("connection", function connection(socket, request) {
       } as AckMessage)
     );
     socket.close(code, `closing connection. reason: ${reason}`);
+    handleCloseConnection(authorId);
   };
 
-  let authorID: string;
-  {
-    let ip: string | undefined;
-    if (request.headers["x-forwarded-for"] !== undefined) {
-      const forwardedFor = request.headers["x-forwarded-for"];
-      ip =
-        typeof forwardedFor === "string"
-          ? forwardedFor.split(",")[0]?.trim()
-          : forwardedFor[0];
-    } else {
-      ip = request.socket.remoteAddress;
-    }
-    if (ip === undefined) {
-      close("could not generate author id", 1008);
-      console.error("connection without IP. closing.");
-      return;
-    }
-    authorID = hash(ip + SALT);
-  }
+  const authorId: string = hash(nextId++ + SALT);
 
   socket.on("message", function (rawMessage: string) {
     const message = JSON.parse(rawMessage);
     if (!isServerMessage(message)) {
       console.error(`Unexpected message received from client \`${message}\``);
+      return;
     }
+
     if (isTextMessage(message)) {
-      handleTextMessage(message, authorID);
+      if (message.author === authorId) {
+        handleTextMessage(message, authorId);
+      }
     }
+
     clearTimeout(closeTimeout);
     closeTimeout = setTimeout(close, timeout);
   });
@@ -88,14 +87,16 @@ webSocketServer.on("connection", function connection(socket, request) {
     console.log("closed a connection");
   });
 
-  console.log("new client connected! ID:", authorID);
+  console.log("new client connected! ID:", authorId);
   socket.send(
     JSON.stringify({
-      type: MessageType.ACK,
-      date: Date.now(),
+      type: MessageType.ID_RESPONSE,
       __ctx: "connected successfully",
-    } as AckMessage)
+      date: Date.now(),
+      authorId,
+    } as IdResponseMessage)
   );
+  activeConnections.add(authorId);
   let closeTimeout = setTimeout(close, timeout);
 });