Say why MakerWorld files didn't download instead of importing silently without them

MakerWorld answers an expired or missing auth token with {"error": "Please log
in to download models."} and no download link, which was skipped without a
word, so imports and "Download files from source" just ended with no files.
Now the reason comes back: missing settings, a refused token (probably expired),
no printable files on the page, or a failed download. The import screen shows
it, and the Settings hint explains where the token comes from.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

lib/importers/makerworld.js

@@ -35,10 +35,21 @@ async function resolveDownload(flaresolverrUrl, instanceId, token) {
   });
 }
 
+// Why a download-link answer came back without a link, in words you can act on;
+// null when it has one. Not logged in: {"code":1,"error":"Please log in to download models."}
+function downloadProblem(answer) {
+  if (answer && answer.url) return null;
+  const detail = String((answer && (answer.error || answer.message || answer.msg)) || '').trim();
+  if (/log ?in|sign ?in|unauthori[sz]ed|token|expired/i.test(detail)) {
+    return 'MakerWorld didn’t accept your auth token (it has probably expired). Paste a fresh one in Settings → MakerWorld auth token, then use “Download files from source”.';
+  }
+  return `MakerWorld didn’t give a download link${detail ? `: ${detail}` : ''}`;
+}
+
 // Pull the license string out of the page data (e.g. "MakerWorld Exclusive License").
 function parseLicense(html) {
   const m = html.match(/"license"\s*:\s*"([^"]+)"/);
   return m ? m[1] : null;
 }
 
-module.exports = { parseInstances, resolveDownload, parseLicense };
+module.exports = { parseInstances, resolveDownload, downloadProblem, parseLicense };

public/app.js

@@ -2252,10 +2252,13 @@ async function handleImport(e) {
     if (res.ok) {
       await loadData();
       if (data.metadataOnly) {
-        status.textContent = data.metadataFetched
+        status.textContent = data.filesError
+          ? `Imported "${data.name}", but its files couldn’t be downloaded: ${data.filesError}`
+          : data.metadataFetched
             ? `Imported "${data.name}". Opening it so you can add the downloaded files…`
             : `Couldn't read that page (the site blocks automated access), so I created a stub named "${data.name}". Opening it so you can add files…`;
-        setTimeout(() => { closeModal(importModal); openModelDetail(data.id); }, 1200);
+        // Give a download problem time to be read before moving on.
+        setTimeout(() => { closeModal(importModal); openModelDetail(data.id); }, data.filesError ? 6000 : 1200);
       } else {
         status.textContent = `Imported "${data.name}" with ${data.files.length} file(s).`;
         setTimeout(() => closeModal(importModal), 900);

public/index.html

@@ -320,8 +320,10 @@
                    placeholder="Bearer token from your logged-in session" autocomplete="off">
             <p class="form-hint">
               Status: <span class="setting-status" data-status="makerworld_token">—</span>.
-              Lets Printhive download files from MakerWorld using your account. Paste the bearer
-              token from your logged-in browser session (see instructions in chat).
+              Lets Printhive download files from MakerWorld using your account. In a browser signed in to
+              makerworld.com, open the developer tools (Application / Storage → Cookies → makerworld.com)
+              and copy the value of the <code>token</code> cookie. It expires after a while: paste a new one if
+              MakerWorld downloads stop working.
             </p>
             <button type="button" class="btn btn-link clear-setting" data-setting="makerworld_token">Clear token</button>
           </div>

server.js

@@ -444,6 +444,7 @@ app.post('/api/models/:id/download-files', async (req, res, next) => {
 // original name is already present.
 async function fetchSourceFiles(model, skipNames) {
   if (model.source_site === 'makerworld') {
+    await requireMakerworldSettings(); // before the page fetch, which fails without FlareSolverr
     const html = await fetchPageHtml(model.source_url);
     return downloadMakerworldFiles(html, skipNames);
   }
@@ -828,11 +829,13 @@ app.post('/api/import', async (req, res, next) => {
     // Download the actual files where we can (MakerWorld via FlareSolverr+token,
     // Printables via its public GraphQL API), and capture the license.
     let files = [];
+    let filesError = null; // why no files could be downloaded, shown after the import
     let license = meta.license || null;
     let commercial = null;
     if (detected.site === 'makerworld' && html) {
       files = await downloadMakerworldFiles(html).catch((err) => {
         console.warn('MakerWorld file download failed:', err.message);
+        filesError = err.message;
         return [];
       });
       license = makerworld.parseLicense(html) || license;
@@ -840,6 +843,7 @@ app.post('/api/import', async (req, res, next) => {
     } else if (detected.site === 'printables' && detected.id) {
       const result = await downloadPrintablesFiles(detected.id).catch((err) => {
         console.warn('Printables file download failed:', err.message);
+        filesError = err.message;
         return { files: [] };
       });
       files = result.files;
@@ -869,7 +873,7 @@ app.post('/api/import', async (req, res, next) => {
       files,
     });
     fingerprint.kick();
-    res.status(201).json({ ...publicModel(model), metadataOnly: files.length === 0, metadataFetched });
+    res.status(201).json({ ...publicModel(model), metadataOnly: files.length === 0, metadataFetched, filesError });
   } catch (e) { next(e); }
 });
 
@@ -918,14 +922,28 @@ async function resolveCommercial(licenseName, fallback) {
 
 // Download every printable instance of a MakerWorld model (needs token + FlareSolverr).
 // skipNames: original filenames already present (so a re-download only adds new ones).
-async function downloadMakerworldFiles(html, skipNames = new Set()) {
+// MakerWorld downloads need both a FlareSolverr address and your auth token.
+async function requireMakerworldSettings() {
   const { value: token } = await resolveSetting('makerworld_token');
   const { value: flareUrl } = await resolveSetting('flaresolverr_url');
-  if (!token || !flareUrl) return [];
+  if (!token || !flareUrl) {
+    throw Object.assign(new Error('Add your MakerWorld auth token and FlareSolverr URL in Settings to download MakerWorld files.'), { status: 400 });
+  }
+  return { token, flareUrl };
+}
+
+// Downloads a MakerWorld model's files. When nothing could be downloaded it throws
+// with the reason (missing settings, an expired token, …) so the import can say why.
+async function downloadMakerworldFiles(html, skipNames = new Set()) {
+  const { token, flareUrl } = await requireMakerworldSettings();
 
   const instances = makerworld.parseInstances(html);
+  if (!instances.length) {
+    throw Object.assign(new Error('Couldn’t find any printable files on the MakerWorld page.'), { status: 502 });
+  }
   ensureUploadDir();
   const files = [];
+  const problems = [];
   for (let i = 0; i < instances.length; i++) {
     if (i > 0) await sleep(1200); // give FlareSolverr's browser room between calls
     const inst = instances[i];
@@ -934,18 +952,29 @@ async function downloadMakerworldFiles(html, skipNames = new Set()) {
       dl = await makerworld.resolveDownload(flareUrl, inst.id, token);
     } catch (err) {
       console.warn(`MakerWorld instance ${inst.id} resolve failed:`, err.message);
+      problems.push(`Couldn’t ask MakerWorld for a download link: ${err.message}`);
+      continue;
+    }
+    const problem = makerworld.downloadProblem(dl);
+    if (problem) {
+      console.warn(`MakerWorld instance ${inst.id}: ${problem}`);
+      problems.push(problem);
       continue;
     }
-    if (!dl || !dl.url) continue;
     const original = dl.name || `instance-${inst.id}.3mf`;
     if (skipNames.has(original)) continue;
     const resp = await fetch(dl.url);
-    if (!resp.ok) { console.warn(`MakerWorld CDN download ${resp.status} for ${original}`); continue; }
+    if (!resp.ok) {
+      console.warn(`MakerWorld CDN download ${resp.status} for ${original}`);
+      problems.push(`Downloading ${original} from MakerWorld failed (HTTP ${resp.status})`);
+      continue;
+    }
     const fileName = uniqueName(original);
     const filePath = path.join(UPLOAD_DIR, fileName);
     fs.writeFileSync(filePath, Buffer.from(await resp.arrayBuffer()));
     files.push(describeFile(filePath, fileName, original));
   }
+  if (!files.length && problems.length) throw Object.assign(new Error(problems[0]), { status: 502 });
   return files;
 }
 

test/makerworld.test.js

@@ -0,0 +1,27 @@
+// MakerWorld importer helpers (lib/importers/makerworld.js).
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const makerworld = require('../lib/importers/makerworld');
+
+const page = (design) =>
+  `<html><script id="__NEXT_DATA__" type="application/json">${JSON.stringify({ props: { pageProps: { design } } })}</script></html>`;
+
+test('printable instances and the license are read from the page data', () => {
+  const html = page({
+    license: 'Standard Digital File License',
+    instances: [{ id: 650088, title: 'AMS - 0.4 Nozzle - 0.08 Layer' }, { id: 650089 }],
+  });
+  assert.deepEqual(makerworld.parseInstances(html), [
+    { id: 650088, title: 'AMS - 0.4 Nozzle - 0.08 Layer' },
+    { id: 650089, title: '' },
+  ]);
+  assert.equal(makerworld.parseLicense(html), 'Standard Digital File License');
+  assert.deepEqual(makerworld.parseInstances('<html><title>Just a moment...</title></html>'), []);
+});
+
+test('a download answer without a link says why', () => {
+  assert.equal(makerworld.downloadProblem({ name: 'bookmarks.3mf', url: 'https://cdn.example/bookmarks.3mf' }), null);
+  assert.match(makerworld.downloadProblem({ code: 1, error: 'Please log in to download models.' }), /token \(it has probably expired\)/);
+  assert.equal(makerworld.downloadProblem({ code: 7, error: 'Model not found' }), 'MakerWorld didn’t give a download link: Model not found');
+  assert.equal(makerworld.downloadProblem(null), 'MakerWorld didn’t give a download link');
+});