node-mongo-demo

commit 939669ac30edc32952cd6ac19254bd0e11e3994e
parent 37b0b6f51d86bef17f6ce513bcb49d537d479cab
Author: Jul <jul@9o.is>
Date:   Mon, 27 Jan 2025 11:25:06 -0500

refactor EventStream class

Diffstat:
M
backend/src/api/lucky7-bets-events.js
 | 
22
++++++----------------
A
backend/src/utils/event-stream.js
 | 
29
+++++++++++++++++++++++++++++
M
frontend/src/components/Lucky7.js
 | 
2
+-

3 files changed, 36 insertions(+), 17 deletions(-)
diff --git a/backend/src/api/lucky7-bets-events.js b/backend/src/api/lucky7-bets-events.js
@@ -1,10 +1,7 @@
 import Lucky7Bet from "../models/lucky7-bet.js";
+import EventStream from "../utils/event-stream.js";
 import { dateDifferenceInSeconds } from "../services/lucky7-session.js";
 
-const writeJson = (response, data) => {
-  response.write(JSON.stringify(data))
-};
-
 const lucky7BetsEvents = async (req, res) => {
   const { id } = req.params;
   const { userId } = req;
@@ -36,18 +33,12 @@ const lucky7BetsEvents = async (req, res) => {
         return res.status(200).json(finished);
       }
 
-      res.writeHead(200, {
-        'Content-Type': 'text/event-stream',
-        'Connection': 'keep-alive',
-        'Cache-Control': 'no-cache'
-      });
-
-      writeJson(res, pending);
+      const stream = new EventStream(req, res);
 
       const timeoutId = setTimeout(async () => {
         const bet = await Lucky7Bet.findById(id).exec();
 
-        writeJson(res, {
+        stream.writeJson({
           id: bet.id,
           rollAt: bet.rollAt,
           lucky: bet.lucky,
@@ -56,12 +47,11 @@ const lucky7BetsEvents = async (req, res) => {
           state: "finished",
         });
 
-        res.end();
+        stream.close();
       }, timeout);
 
-      req.on('close', () => {
-        clearTimeout(timeoutId);
-      });
+      stream.writeJson(pending);
+      stream.onClose(() => clearTimeout(timeoutId));
   } catch (error) {
     console.error(error);
     res.status(500).json({ message: "Something went wrong" });
diff --git a/backend/src/utils/event-stream.js b/backend/src/utils/event-stream.js
@@ -0,0 +1,29 @@
+class EventStream {
+    #request;
+    #response;
+
+    constructor(request, response) {
+        this.#request = request;
+        this.#response = response;
+
+        this.#response.writeHead(200, {
+            'Content-Type': 'text/event-stream',
+            'Connection': 'keep-alive',
+            'Cache-Control': 'no-cache'
+        });
+    }
+
+    writeJson(data) {
+        this.#response.write('data: ' + JSON.stringify(data) + '\n\n');
+    }
+
+    close() {
+        this.#response.end();
+    }
+
+    onClose(callback) {
+        this.#request.on('close', callback);
+    }
+}
+
+export default EventStream;
diff --git a/frontend/src/components/Lucky7.js b/frontend/src/components/Lucky7.js
@@ -34,7 +34,7 @@ const useBetEvents = (id, onEvent) => {
                     setListening(false);
                     break;
                 }
-                const json = JSON.parse(value);
+                const json = JSON.parse(value.slice(5));
                 setEvents((events) => [...events, json])
                 onEvent(json);
             }