Interviewer — Suppose we are giving the user option to upload a file and save it. Then how will you send the file to the backend?
Me — We can directly send it in the body of a POST API call…

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Learn how to send large files from frontend to backend using FileReader in JavaScript. Split the file into small chunks and stream them to the backend. Send the file name as a query parameter for unique identification.

Send large files from frontend to the backend

i would suggest sending the file to a CDN from frontend in addition to this POST then the CDN will respond with the files metadata that include the url then send that url to you backend that will store in your database , this will assist you in the long run as cdn do more than storing but also file optimisation etc , check out cloudinary it has a really generous free tier

You should match checksum for uploaded file in order to check that all pieces are uploaded correctly.

This is a helpful article for anyone looking to implement file uploads in their web application.

You can also use the new stream API. a File object has now access to a stream via the stream method (const stream = file.stream()). Then you can read it chunk by chunk by using the default stream reader that comes with every stream (const reader = stream.getReader()) with the read method (const {value, done} = await reader.read()). You loop until “done” is true.