refactor: Reintroduce history endpoints for resource versioning and rollback functionality in server, ensuring proper initialization and organization of code

backend/server.js

@@ -1,39 +1,4 @@
-// History endpoints (require bucket versioning to be enabled). If versioning disabled, best effort.
-app.get('/api/history/:resource', async (req, res) => {
-  const { resource } = req.params;
-  const key = resourceToKey(resource);
-  if (!key) return sendError(res, 400, 'Unknown resource', 'E_RESOURCE');
-  try {
-    if (!s3.listObjectVersions) {
-      return sendError(res, 501, 'S3 listObjectVersions not available', 'E_NOT_SUPPORTED');
-    }
-    const out = await s3.listObjectVersions({ Bucket: BUCKET_NAME, Prefix: key, MaxKeys: 20 }).promise();
-    const versions = (out.Versions || [])
-      .filter(v => v.Key === key)
-      .slice(0, 10)
-      .map(v => ({ versionId: v.VersionId, isLatest: v.IsLatest, lastModified: toIso(v.LastModified), size: v.Size, etag: v.ETag }));
-    return res.json({ items: versions });
-  } catch (e) {
-    console.error('history error', e);
-    return sendError(res, 500, 'Error reading history', 'E_S3', { error: String(e?.message || e) });
-  }
-});
-
-app.post('/api/history/:resource/rollback', async (req, res) => {
-  const { resource } = req.params;
-  const { versionId } = req.body || {};
-  const key = resourceToKey(resource);
-  if (!key || !versionId) return sendError(res, 400, 'Bad request', 'E_BAD_REQUEST');
-  try {
-    // Copy specific version over same key to rollback
-    await s3.copyObject({ Bucket: BUCKET_NAME, CopySource: `/${BUCKET_NAME}/${encodeURIComponent(key)}?versionId=${encodeURIComponent(versionId)}`, Key: key }).promise();
-    const meta = await headMeta(key);
-    return sendOk(res, meta);
-  } catch (e) {
-    console.error('rollback error', e);
-    return sendError(res, 500, 'Error rollback', 'E_S3', { error: String(e?.message || e) });
-  }
-});
+// History endpoints are registered below after app is initialized
 require('dotenv').config();
 const express = require('express');
 const AWS = require('aws-sdk');
@@ -42,6 +7,7 @@ const path = require('path');
 const compression = require('compression');
 const Ajv = require('ajv');
 const net = require('net');
+const crypto = require('crypto');
 
 const app = express();
 const port = 3001;
@@ -97,6 +63,21 @@ function resourceToKey(resource) {
   }
 }
 
+// Compute sha256 of string
+function sha256OfString(s) {
+  return crypto.createHash('sha256').update(Buffer.from(String(s), 'utf-8')).digest('hex');
+}
+
+function mapAjvErrors(errors) {
+  if (!Array.isArray(errors)) return [];
+  return errors.map((e) => ({
+    message: e.message,
+    instancePath: e.instancePath,
+    keyword: e.keyword,
+    params: e.params,
+  }));
+}
+
 // Serve static files from the React app
 app.use(express.static(path.join(__dirname, 'public')));
 
@@ -1020,6 +1001,43 @@ app.delete('/api/locks/:resource', (req, res) => {
     res.json({ released: true });
 });
 
+// History endpoints (require bucket versioning to be enabled). If versioning disabled, best effort.
+app.get('/api/history/:resource', async (req, res) => {
+  const { resource } = req.params;
+  const key = resourceToKey(resource);
+  if (!key) return sendError(res, 400, 'Unknown resource', 'E_RESOURCE');
+  try {
+    if (!s3.listObjectVersions) {
+      return sendError(res, 501, 'S3 listObjectVersions not available', 'E_NOT_SUPPORTED');
+    }
+    const out = await s3.listObjectVersions({ Bucket: BUCKET_NAME, Prefix: key, MaxKeys: 20 }).promise();
+    const versions = (out.Versions || [])
+      .filter(v => v.Key === key)
+      .slice(0, 10)
+      .map(v => ({ versionId: v.VersionId, isLatest: v.IsLatest, lastModified: toIso(v.LastModified), size: v.Size, etag: v.ETag }));
+    return res.json({ items: versions });
+  } catch (e) {
+    console.error('history error', e);
+    return sendError(res, 500, 'Error reading history', 'E_S3', { error: String(e?.message || e) });
+  }
+});
+
+app.post('/api/history/:resource/rollback', async (req, res) => {
+  const { resource } = req.params;
+  const { versionId } = req.body || {};
+  const key = resourceToKey(resource);
+  if (!key || !versionId) return sendError(res, 400, 'Bad request', 'E_BAD_REQUEST');
+  try {
+    // Copy specific version over same key to rollback
+    await s3.copyObject({ Bucket: BUCKET_NAME, CopySource: `/${BUCKET_NAME}/${encodeURIComponent(key)}?versionId=${encodeURIComponent(versionId)}`, Key: key }).promise();
+    const meta = await headMeta(key);
+    return sendOk(res, meta);
+  } catch (e) {
+    console.error('rollback error', e);
+    return sendError(res, 500, 'Error rollback', 'E_S3', { error: String(e?.message || e) });
+  }
+});
+
 // Generate MikroTik configuration from filters
 app.get('/api/filters/generate-config', async (req, res) => {
     const params = {