how to make a downloaded file has file name + file extension in its name?

how to make a downloaded file has file name + file extension in its name?

I want to download the file from 'File Upload' Field in Zoho CRM, after download the file then I will upload it to our own image server to create a download URL link. I wrote the code below.

but the problem is, the file name doesnt have file extension in it. so how to include a file name + file extension in the downloaded file name?

here is the code I use:

  2. // fetch CRM Deal Details
  3. v_Module = "Deals";
  4. v_dealID = DEAL_ID;
  5. v_Endpoint = "https://www.zohoapis.com/crm/v7/" + v_Module + "/" + v_dealID;
  6. r_DealDetails = invokeurl
  7. [
  8. url :v_Endpoint
  9. type :GET
  10. connection:"zoho_crm_connections"
  11. ];
  12. m_DealDetails = ifnull(r_DealDetails.get("data").toMap(),Map());
  13. if(!isNull(m_DealDetails.get("Product_Attachment")))
  14. {
  15. l_Files = List();
  16. for each  m_FileUpload in m_DealDetails.get("Product_Attachment")
  17. {
  18. // get files from Zoho CRM
  19. v_FileDownloadUrl = "https://www.zohoapis.com/crm/v7/files?id=" + m_FileUpload.get("File_Id__s");
  20. v_FileName = m_FileUpload.get("File_Name__s"); // I am trying to get name and extension in here
  21. f_MyFile = invokeurl
  22. [
  23. url :v_FileDownloadUrl
  24. type :GET
  25. connection:"zoho_crm_connections"
  26. ];
  27. f_MyFile.setParamName("file_data");
  28. f_MyFile.setFileName(v_FileName); // set the file name in here but it doesnt work
  29. l_Files.add(f_MyFile);
  30. }
  31. if(!l_Files.isEmpty())
  32. {
  33. first_file = l_Files.get(0);
  34. // send first file only to Blueray Server
  35. bodyMap = Map();
  36. bodyMap.put("file_data",first_file);
  37. fileResponse = invokeurl
  38. [
  39. url :"https://myAPI.com/file/upload"
  40. type :POST
  41. parameters:bodyMap
  42. ];
  43. file_url = fileResponse.get("file_url");
  44. // update the field in deal module
  45. update = {"Product_Attachment_URL":file_url};
  46. zoho.crm.updateRecord("Deals",DEAL_ID,update);
  47. }
  48. }