From d1a06866c95b9eb9aebf412d391a3ab12797fca5 Mon Sep 17 00:00:00 2001
From: Denis Shatskiy <admin@shts.su>
Date: Mon, 11 Aug 2025 16:03:51 +0700
Subject: [PATCH] feat: Enhance CORS support by exposing important headers and
 update API responses to include Last-Modified and Content-Length-Source for
 improved client-side handling

---
 backend/server.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/backend/server.js b/backend/server.js
index b1be61b..ead40e6 100644
--- a/backend/server.js
+++ b/backend/server.js
@@ -14,6 +14,12 @@ app.use(cors());
 app.use(express.json());
 app.use(compression());
 
+// Expose important headers to browser JS (for CORS)
+app.use((req, res, next) => {
+  res.setHeader('Access-Control-Expose-Headers', 'ETag, Last-Modified, Content-Length-Source');
+  next();
+});
+
 // Serve static files from the React app
 app.use(express.static(path.join(__dirname, 'public')));
 
@@ -377,6 +383,11 @@ app.post('/api/asns', async (req, res) => {
     try {
         const put = await s3.putObject(params).promise();
         if (put.ETag) res.set('ETag', String(put.ETag));
+        try {
+            const head = await s3.headObject({ Bucket: BUCKET_NAME, Key: 'bgp_data/asns.txt' }).promise();
+            if (head.LastModified) res.set('Last-Modified', new Date(head.LastModified).toUTCString());
+            if (typeof head.ContentLength === 'number') res.set('Content-Length-Source', String(head.ContentLength));
+        } catch {}
         res.send('File updated successfully');
     } catch (error) {
         console.error(error);
@@ -460,6 +471,11 @@ app.post('/api/domains-new', async (req, res) => {
     try {
         const put = await s3.putObject(params).promise();
         if (put.ETag) res.set('ETag', String(put.ETag));
+        try {
+            const head = await s3.headObject({ Bucket: BUCKET_NAME, Key: 'bgp_data/domains_community.txt' }).promise();
+            if (head.LastModified) res.set('Last-Modified', new Date(head.LastModified).toUTCString());
+            if (typeof head.ContentLength === 'number') res.set('Content-Length-Source', String(head.ContentLength));
+        } catch {}
         res.send('File updated successfully');
     } catch (error) {
         console.error(error);
@@ -543,6 +559,11 @@ app.post('/api/ip-ranges', async (req, res) => {
     try {
         const put = await s3.putObject(params).promise();
         if (put.ETag) res.set('ETag', String(put.ETag));
+        try {
+            const head = await s3.headObject({ Bucket: BUCKET_NAME, Key: 'bgp_data/ips.txt' }).promise();
+            if (head.LastModified) res.set('Last-Modified', new Date(head.LastModified).toUTCString());
+            if (typeof head.ContentLength === 'number') res.set('Content-Length-Source', String(head.ContentLength));
+        } catch {}
         res.send('File updated successfully');
     } catch (error) {
         console.error(error);