How to transfer multiple files?

[saudkhan116]

I am trying to transfer multiple files by extending the 04.0-file-transfer example at my own. The current example transfers a signle text file (test-document.txt).

I would like to ask few questions:

1. If files are transmitted from the same provider and/or different provider, would I need to create a separate contractoffer.json for each file (asset) like contractoffer1.json for test-document1 and contractoffer2.json for test-document2 or a single contractoffer.json is enough.
2. From where can I get the documentation for contractoffer.json file so that I can understand the attributes better used in json file.
3. What major change I have to deal with multiple files in codebase

Thanks in advance!