Optimize memory usage - WebSocket object as peer

Author: mrlika

lib/fast-tracker.ts

@@ -129,7 +129,7 @@ export class FastTracker implements Tracker {
             info_hash: infoHash,
             complete: swarm.completedCount,
             incomplete: swarm.peers.size - swarm.completedCount,
-        });
+        }, peer);
 
         this.sendOffersToPeers(json, swarmPeers, peer, infoHash);
     }
@@ -238,7 +238,7 @@ export class FastTracker implements Tracker {
         }
 
         delete json.to_peer_id;
-        toPeer.sendMessage(json);
+        toPeer.sendMessage(json, toPeer);
 
         if (debugEnabled) {
             debug("answer: from peer", Buffer.from(peer.id!).toString("hex"), "to peer", Buffer.from(toPeerId).toString("hex"));
@@ -325,7 +325,7 @@ export class FastTracker implements Tracker {
         peer.sendMessage({
             action: "scrape",
             files: files,
-        });
+        }, peer);
     }
 }
 
@@ -394,7 +394,7 @@ function sendOffer(offerItem: {offer?: { sdp?: string }, offer_id?: string } | n
             type: "offer",
             sdp: offer.sdp, // offer.sdp is not validated to be a string
         },
-    });
+    }, toPeer);
 }
 
 function removePeerFromSwarm(peer: InternalPeerContext, infoHash: string): Swarm | undefined {

lib/tracker.ts

@@ -16,7 +16,7 @@
 
 export interface PeerContext {
     id?: string;
-    sendMessage: (json: any) => void;
+    sendMessage: (json: any, peer: PeerContext) => void;
 }
 
 export interface Tracker {

lib/uws-tracker.ts

@@ -15,7 +15,7 @@
  */
 
 import { App, SSLApp, WebSocket, HttpRequest, TemplatedApp } from "uWebSockets.js";
-import { Tracker, PeerContext, TrackerError } from "./tracker";
+import { Tracker, TrackerError } from "./tracker";
 import { StringDecoder } from "string_decoder";
 
 import * as Debug from "debug";
@@ -104,18 +104,16 @@ export class UWebSocketsTracker {
             return;
         }
 
-        let peer: PeerContext | undefined = ws.peer;
-        if (peer === undefined) {
-            peer = createPeer(ws);
-            ws.peer = peer;
+        if (ws.sendMessage === undefined) {
+            ws.sendMessage = sendMessage;
         }
 
         if (debugMessagesEnabled) {
-            debugMessages("in", peer.id !== undefined ? Buffer.from(peer.id).toString("hex") : "unknown peer", json);
+            debugMessages("in", ws.id !== undefined ? Buffer.from(ws.id).toString("hex") : "unknown peer", json);
         }
 
         try {
-            this.tracker.processMessage(json, peer);
+            this.tracker.processMessage(json, ws as any);
         } catch (e) {
             if (e instanceof TrackerError) {
                 debugWebSockets("failed to process message from the peer:", e);
@@ -128,24 +126,20 @@ export class UWebSocketsTracker {
 
     private onClose = (ws: WebSocket, code: number, message: ArrayBuffer) => {
         this.webSocketsCount--;
-        const peer: PeerContext | undefined = ws.peer;
 
-        if (peer !== undefined) {
-            delete ws.peer;
-            this.tracker.disconnectPeer(peer);
+        if (ws.sendMessage !== undefined) {
+            this.tracker.disconnectPeer(ws as any);
+            delete ws.sendMessage;
+            delete ws.id;
         }
 
         debugWebSockets("closed with code", code);
     }
 }
 
-function createPeer(ws: WebSocket): PeerContext {
-    return {
-        sendMessage: (json: any) => {
-            ws.send(JSON.stringify(json), false, false);
-            if (debugMessagesEnabled) {
-                debugMessages("out", ws.peer.id !== undefined ? Buffer.from(ws.peer.id).toString("hex") : "unknown peer", json);
-            }
-        },
-    };
+function sendMessage(json: any, ws: WebSocket) {
+    ws.send(JSON.stringify(json), false, false);
+    if (debugMessagesEnabled) {
+        debugMessages("out", ws.id !== undefined ? Buffer.from(ws.id).toString("hex") : "unknown peer", json);
+    }
 }