将 base64 字符串数据转换为 PDF 文件以从 API 下载 - NodeJS

Question

I have a nodeJS API configured which connects to another API and retrieves a data object, which is a Base64 string.

The client that calls the API endpoint needs to download a PDF file that is made from the base64 data.

How should the data be returned to the client so that it can be converted/prompt download from the browser? Should this be done client or server-side?

Answer 1

Base64 is HTML safe and has utility when you want to create a data URL as a link. This would allow to preload the PDF so that the user instantly gets the file when clicking the link.

However, you just want to download it directly, so just convert it as binary on server side to reduce the network overhead related to base64, and keep the client as light as possible (load less data, use less resources).

Just set the proper content-type in the response ( application/pdf if you want the PDF to be opened with the browser's PDF plugin, or application/octet-stream if you want to trigger a regular download) then just create a link to it with a classic <a href=... . You can also do one of the following:

• Set the download attribute to the link on client side.
• Set the Content-Disposition: attachment header on server side.