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:

1. 
   
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. }