From 3eeece6a540f9ab6052a8f07eed02917cfc791fa Mon Sep 17 00:00:00 2001
From: HF <pixelplanetdev@gmail.com>
Date: Tue, 1 Feb 2022 00:53:28 +0100
Subject: [PATCH] check if emptytile.png exists before sending it

---
 src/routes/tiles.js | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/routes/tiles.js b/src/routes/tiles.js
index 4594cd4e..bb6dda99 100644
--- a/src/routes/tiles.js
+++ b/src/routes/tiles.js
@@ -2,11 +2,10 @@
  *
  * Serve zoomlevel tiles
  *
- * @flow
  */
 
+import fs from 'fs';
 import express from 'express';
-import type { Request, Response } from 'express';
 import { TILE_FOLDER } from '../core/config';
 import { HOUR } from '../core/constants';
 
@@ -25,15 +24,25 @@ router.use('/', express.static(TILE_FOLDER, {
  * catch File Not Found: Send empty tile
  */
 router.use('/:c([0-9]+)/:z([0-9]+)/:x([0-9]+)/:y([0-9]+).png',
-  async (req: Request, res: Response) => {
+  async (req, res) => {
     const { c: paramC } = req.params;
     const c = parseInt(paramC, 10);
+
+    const filename = `${TILE_FOLDER}/${c}/emptytile.png`;
+    if (!fs.existsSync(filename)) {
+      res.set({
+        'Cache-Control': `public, s-maxage=${24 * 3600}, max-age=${24 * 3600}`,
+      });
+      res.status(404).end();
+      return;
+    }
+
     res.set({
       'Cache-Control': `public, s-maxage=${2 * 3600}, max-age=${1 * 3600}`,
       'Content-Type': 'image/png',
     });
     res.status(200);
-    res.sendFile(`${TILE_FOLDER}/${c}/emptytile.png`);
+    res.sendFile(filename);
   });