add: improved the frontend and the backend by adding websockets

back/api/channels.js

@@ -11,6 +11,16 @@ router.get('/', async (req, res) => {
     res.send(channels);
 });
 
+const sockets = new Set();
+
+router.ws('/', function(ws, req) {
+    sockets.add(ws);
+
+    ws.on('close', () => {
+        sockets.delete(ws);
+    });
+});
+
 router.get('/:name', async (req, res) => {
     const name = req.params.name;
     const connection = await getConnection();
@@ -23,6 +33,22 @@ router.get('/:name', async (req, res) => {
     }
 });
 
+const channelSockets = new Map();
+
+router.ws('/:name', function(ws, req) {
+    const name = req.params.name;
+
+    if (!channelSockets.has(name)) {
+        channelSockets.set(name, new Set());
+    }
+
+    channelSockets.get(name).add(ws);
+
+    ws.on('close', () => {
+        channelSockets.get(name).delete(ws);
+    });
+});
+
 router.get('/:name/messages', async (req, res) => {
     const name = req.params.name;
     const connection = await getConnection();
@@ -78,6 +104,23 @@ router.post('/:name/messages/send', async (req, res) => {
     }
 
     connection.end();
+
+    if (sockets.size > 0) {
+        for (const client of sockets) {
+            if (client.readyState === 1) {
+                client.send('new_message');
+            }
+        }
+    }
+
+    if (channelSockets.has(name)) {
+        for (const client of channelSockets.get(name)) {
+            if (client.readyState === 1) {
+                client.send('new_message');
+            }
+        }
+    }
+
     res.send({ message: 'Message sent' });
 });
 
@@ -113,6 +156,23 @@ router.post('/:name/messages/delete', async (req, res) => {
     await deleteMessage(connection, message_id);
     await deleMentions(connection, message_id);
     connection.end();
+
+    if (sockets.size > 0) {
+        for (const client of sockets) {
+            if (client.readyState === 1) {
+                client.send('delete_message');
+            }
+        }
+    }
+
+    if (channelSockets.has(name)) {
+        for (const client of channelSockets.get(name)) {
+            if (client.readyState === 1) {
+                client.send('delete_message');
+            }
+        }
+    }
+
     res.send({ message: 'Message deleted' });
 });
 
@@ -140,6 +200,15 @@ router.post('/add', async (req, res) => {
 
     await addChannel(connection, name, description, user.id);
     connection.end();
+
+    if (sockets.size > 0) {
+        for (const client of sockets) {
+            if (client.readyState === 1) {
+                client.send('new_channel');
+            }
+        }
+    }
+
     res.send({ message: 'Channel added' });
 });