Change all_sessions to buttons

static/renderer.js

@@ -12,6 +12,17 @@ ws.onmessage = function(event) {
     }
 
     if (msg.hasOwnProperty('allsessions')) {
-        document.getElementById('all_sessions').innerText = msg.allsessions.join(', ');
+        const all_sessions = document.getElementById('all_sessions');
+
+        while (all_sessions.children.length) all_sessions.lastChild.remove();
+
+        for (let session of msg.allsessions) {
+            const button = document.createElement('button');
+            button.innerText = session;
+            button.onclick = async (e) => await fetch('api/join_session', {
+                method: 'POST', body: JSON.stringify({sessionid: session})
+            });
+            all_sessions.appendChild(button);
+        }
     }
 };

ui.html

@@ -10,7 +10,7 @@
 this is the UI
 <br>
 <span id="current_session">You are not in any session.</span><br>
-<span id="all_sessions"></span><br>
+<div id="all_sessions"></div><br>
 <br>
 <button id="btn_create_session">Create session</button>
 <br><br><br>