How to download file in memory and then upload it to somewhere else

Question

I would like to do create a tempermonkey script that would download a file on a site without bothering the user with saving it on the disk. So the file would be stored in a variable, which the script would be able to use to upload that file to my remote server.

Is it possible to do in browser javascript?

Diagram:

Diagram

But why even pass through the user's machine? You can just get the link and download directly from your server — aviya.developer, Jul 09 '19 at 11:44
@aviya.developer - it's a good point, why use someone else browser to get data from someone elses website — Jaromanda X, Jul 09 '19 at 11:45
Might require the user to be logged in to download the file. — NickSlash, Jul 09 '19 at 11:56
@NickSlash you are correct. The file must be downloaded under authenticated user when he performs an action. — Linux_cat, Jul 09 '19 at 12:05

score 3 · Accepted Answer · answered Jul 09 '19 at 11:50

3

One option would be to download the file as a blob using fetch:

async function upload() {
  const res = await fetch('https://example.com/download-endpoint')
  const blob = await res.blob()

  fetch('https://example.com/upload-endpoint', {
    method: 'POST',
    headers: {
      'Content-Type': blob.type
    },
    body: blob
  })
}

answered Jul 09 '19 at 11:50

Pavlo

43,301
14
77
113

this is pretty simple, straightforward answer. Easy to understand. Thank you – Linux_cat Jul 09 '19 at 12:10

How to download file in memory and then upload it to somewhere else

1 Answers1

Linked