Simplified file retrieval from Vercel Sandbox environments

Laurens DuijvesteijnSoftware Engineer

1 min read

The Vercel Sandbox SDK now includes two new methods that make file retrieval simple.

When you run code in a Vercel Sandbox, that code can generate files like a CSV report, a processed image, or a PDF invoice. These files are created inside isolated VMs, so they need to be retrieved across a network boundary. Until now, this required manual stream handling with custom piping.

Link to headingDownload a file

If you want to download a generated report from your sandbox to your local machine, you can use downloadFile() to seamlessly stream the contents.

const dstPath = await sandbox.downloadFile(
{ path: 'generated-file.csv', cwd: '/vercel/sandbox' },
{ path: 'generated-file.csv', cwd: '/tmp' }
);

Link to headingRead file contents to buffer

Both methods handle the underlying stream operations automatically. For example, if your sandbox runs a script that generates a chart as a PNG, you can pull it out with a single call to readFileToBuffer(), no manual stream wiring needed.

const buffer = await sandbox.readFileToBuffer({ path: 'chart.png' });

Learn more about the Sandbox SDK or explore the updated documentation.