curl --request POST \
  --url https://api-sandbox.cashfree.com/partners/merchants/{merchant_id}/documents \
  --header 'Content-Type: multipart/form-data' \
  --header 'x-partner-apikey: <x-partner-apikey>' \
  --form 'document_type=<string>' \
  --form file='@example-file'

{
  "document_type": "bank_statement",
  "uploaded_on": "2006-01-02T15:04:05-0700"
}