Cloudinary: unsigned upload with cordova file transfer

Does anyone have a clear example of how to do an unsigned upload to Cloudinary from an Ionic app using an upload_preset?

This is what I’m currently trying but I’m getting the error

Upload preset must be specified when using unsigned upload

var options = {
upload_preset: ‘preset1’,
fileKey: “file”,
fileName: filename,
chunkedMode: false,
mimeType: “video/mp4”,

const fileTransfer = this.transfer.create();
var uploadUrl = "";

return fileTransfer.upload(imageNewPath, uploadUrl, options).then(
  (entry:any) => { console.log(entry);  },
  (err) => { console.log("ERROR: " + JSON.stringify(err)); });

Any ideas?

There’s one in the official Angular example project. Edit: oh wait, maybe not unsigned, I had this in my bookmarks and maybe I clicked too fast.