I do not know about uploading without form.
Just by put a filename in URL ....
Well, and where is the specific data for that filename.
A filename is just empty without something in the file.
How was your idea of submitting the data?
Where should it come from?
If it comes from the users computer, you might as well use the very practical <form>
<input type="file">
If it comes from somewhere else, then I find this is to complicated for me.
🙂