Linearized pdf load incorrectly

Technical Support
1

Which product are you using?

PDF.js.Express Plus
PDF.js Express Version
8.7.4

Detailed description of issue
i tried to load a Linearized pdf file but instead of partial load, webViewer load the whole document. My server has turn on byte range request, and my file is Linearized pdf.)

Expected behaviour
{load file with multiple chunk. }

Does your issue happen with every document, or just one?
{every document}

Link to document
{Provide a link to the document in question if possible}

Code snippet
my web viewer:
WebViewer(
{
path: ‘/public’,
licenseKey: ‘YOUR_KEY_HERE’,
},
viewerRef.current
).then(async (instance) => {
const { docViewer, documentViewer, annotManager, UI, Core } = instance;

  docViewer.loadDocument(`url`);

}
my NodeJs server:

fs.stat(pdfPath, (err, stats) => {
if (err) {
console.error(‘Not Found PDF:’, err);
return res.sendStatus(404);
}

        const fileSize = stats.size;
        const range = req.headers.range;

        if (range) {
          // ex: Range: bytes=0-1023
          const parts = range.replace(/bytes=/, "").split("-");
          const start = parseInt(parts[0], 10);
          const end = parts[1] ? parseInt(parts[1], 10) : fileSize - 1;

          
          const chunkSize = (end - start) + 1;

        
          const file = fs.createReadStream(pdfPath, { start, end });

          // set headers
          const head = {
            'Content-Range': `bytes ${start}-${end}/${fileSize}`,
            'Accept-Ranges': 'bytes',
            'Content-Length': chunkSize,
            'Content-Type': 'application/pdf',
          };

          res.writeHead(206, head);
          file.pipe(res);
        } else {
          // range not found. sent the whole file
          const head = {
            'Content-Length': fileSize,
            'Content-Type': 'application/pdf',
          };
          res.writeHead(200, head);
          fs.createReadStream(pdfPath).pipe(res);
        }
      });
2

Hi there,

Are you able to reproduce this on the demo? PDF.js Viewer Demo | PDF.js Express
Are you getting the 206 fetch requests in the network panel? Are you getting any console error messages?

Best regards,
Kevin Kim