Add cooldown for updates

mates.json

@@ -1 +1 @@
-{"mates":87}
+{"mates":0,"lastUpdate":0}

server.js

@@ -38,7 +38,27 @@ app.post('/mates', function(rq, rs)
 {
     var data = fs.readFileSync('./mates.json');
     var json = JSON.parse(data);
+
+    var cooldownSecs = 60;
+    var currentTime = new Date().getTime();
+    var timeSinceLast = (currentTime - json.lastUpdate) / 1000;
+
+    // Check if update was sent too quickly
+    if (timeSinceLast < cooldownSecs)
+    {
+        rs
+            .status(403)
+            .json({
+                error:"Update sent too quickly",
+                cooldown: cooldownSecs,
+                remaining: Math.ceil(cooldownSecs - timeSinceLast)
+            });
+
+        return;
+    }
+
     json.mates += 1;
+    json.lastUpdate = new Date().getTime();
 
     fs.writeFile('./mates.json', JSON.stringify(json), (err) => {
         if (err)