Create server.js

server.js

@@ -0,0 +1,69 @@
+// server.js – write-access tester
+import express from 'express';
+import fs       from 'fs';
+import fsp      from 'fs/promises';
+import path     from 'path';
+
+const PORT = process.env.PORT || 7860;
+const DIR  = '/data';                     // Space-persistent volume
+const FILE = path.join(DIR, 'test.txt');
+
+const app  = express();
+app.use(express.json());
+
+/* POST /write  -> attempts three save methods */
+app.post('/write', async (_req, res) => {
+  const report = {};
+
+  // ensure /data exists
+  try {
+    fs.mkdirSync(DIR, { recursive: true });
+    report.mkdir = 'ok';
+  } catch (e) {
+    report.mkdir = e.message;
+  }
+
+  /* ---- Method A: sync write ---- */
+  try {
+    fs.writeFileSync(FILE, 'sync write\n', { flag: 'a' });
+    report.sync = 'ok';
+  } catch (e) {
+    report.sync = e.message;
+  }
+
+  /* ---- Method B: fs.promises ---- */
+  try {
+    await fsp.writeFile(FILE, 'promises write\n', { flag: 'a' });
+    report.promise = 'ok';
+  } catch (e) {
+    report.promise = e.message;
+  }
+
+  /* ---- Method C: stream ---- */
+  try {
+    await new Promise((resolve, reject) => {
+      const stream = fs.createWriteStream(FILE, { flags: 'a' });
+      stream.on('error', reject);
+      stream.end('stream write\n', resolve);
+    });
+    report.stream = 'ok';
+  } catch (e) {
+    report.stream = e.message;
+  }
+
+  res.json(report);
+});
+
+/* GET /read  -> returns file contents or error */
+app.get('/read', (req, res) => {
+  try {
+    const txt = fs.readFileSync(FILE, 'utf-8');
+    res.type('text/plain').send(txt);
+  } catch (e) {
+    res.status(500).send(e.message);
+  }
+});
+
+app.listen(PORT, '0.0.0.0', () =>
+  console.log(`📝 Write-test server listening on ${PORT} (DIR=${DIR})`)
+);