No examples of how to use subaction "addFile"

[MatousAc]

I've been having a lot of trouble just adding a file in a folder. The schema defines this subaction, but does not give an example when using source url:
"sourceUrl": {
"type": "string",
"description": "Optional parameter. The location in the tenant to copy the file from, as an absolute url. Provide either this or source."
}

What type of url is needed? This format results in a "Bad Request" error when creating site scripts:
company.sharepoint.com/Folder/Subfolder/Filename.xlsx
And these don't actually add the file in the desired destination:
http://company.sharepoint.com/Folder/Subfolder/Filename.xlsx
https://company.sharepoint.com/Folder/Subfolder/Filename.xlsx

Can anyone show how they did this?