curl --request POST \
  --url https://www.zohoapis.com/writer/api/v1/documents/a1b2c3d4e5f6g7h8i9/sign \
  --header 'Authorization: Zoho-oauthtoken d92d4xxxxxxxxxxxxx15f52' \
  --header 'content-type: multipart/form-data' \
  -F 'recipients=[
  {
    "recipient_1": "john@zylker.com",
    "recipient_name": "John",
    "action_type": "sign"
  }
]' \
  -F 'signed_document_name=SignedDoc' \
  -F 'service_name=zohosign' \
  -F 'subject=Please sign this document' \
  -F 'message=Kindly review and sign the attached document.' \
  -F 'attachments=@file_path' \
  -F 'is_sequential=true' \
  -F 'prefill_data={
  "name": "Amelia"
}' \
  -F 'reminder_period=3' \
  -F 'expire_in=15' \
  -F 'sign_org_id=string' \
  -F 'sign_request_type_id=string' \
  -F 'allowed_cloud_provider_ids=[
  10,
  25
]' \
  -F 'callback_url=https://zylker.com/webhook/sign-complete'

    headersMap = Map();
    headersMap.put("Accept", "application/json");

    list_of_text=List();
    list_of_text.add({"paramName":"recipients","content":"[object Object]","stringPart":"true"});
    list_of_text.add({"paramName":"signed_document_name","content":"SignedDoc","stringPart":"true"});
    list_of_text.add({"paramName":"service_name","content":"zohosign","stringPart":"true"});
    list_of_text.add({"paramName":"subject","content":"Please sign this document","stringPart":"true"});
    list_of_text.add({"paramName":"message","content":"Kindly review and sign the attached document.","stringPart":"true"});
    file=invokeurl
    [
      url : "public fileURL link"
      type : GET
    ];
    list_of_text.add({"paramName":"attachments","content":file,"stringPart":"false"});
    list_of_text.add({"paramName":"is_sequential","content":"true","stringPart":"true"});
    list_of_text.add({"paramName":"prefill_data","content":"[object Object]","stringPart":"true"});
    list_of_text.add({"paramName":"reminder_period","content":"3","stringPart":"true"});
    list_of_text.add({"paramName":"expire_in","content":"1","stringPart":"true"});
    list_of_text.add({"paramName":"sign_org_id","content":"value","stringPart":"true"});
    list_of_text.add({"paramName":"sign_request_type_id","content":"value","stringPart":"true"});
    list_of_text.add({"paramName":"allowed_cloud_provider_ids","content":"10,25","stringPart":"true"});
    list_of_text.add({"paramName":"callback_url","content":"https://zylker.com/webhook/sign-complete","stringPart":"true"});

    response = invokeUrl
    [
        url: "https://www.zohoapis.com/writer/api/v1/documents/{document_id}/sign"
        type: POST
        headers: headersMap
        files: list_of_text
        connection: connection_name
    ]

    info response;