How to browse through box.com folders to select a file and download the selected file - vba

Question

I need a excel macro (vba) to select a file from box.com by iterating though existing folders and at the same time I need to upload the file from my machine to box.com folder using excel macro. I am searching for a long time on net. But no use. Please help or try to give some ideas how to achieve this.
Thanks in advance.
-Edit
I am using the below code for getting authentication token. But I am getting an error message at the place of .send(url). Error message is "The server name or address could not be resolved".
Function getAuthToken()
Dim WinHttpReq As WinHttp.WinHttpRequest
Dim api_key As String
api_key = "{api_key}"
Set WinHttpReq = New WinHttp.WinHttpRequest
strUrl = "https://www.box.net/api/1.0/rest?action=get_ticket&api_key=" & api_key
WinHttpReq.Open Method:="GET", url:=strUrl, async:=False
WinHttpReq.Send
getTicket = WinHttpReq.responseText
Debug.Print getTicket
End Function

Answer 1

Not being a vba expert, I suspect that you'll get more answers if you tag your question with a vba tag. However, some quick scanning around shows that vba can call REST apis by doing something like this:
Dim MyURL as String
MyURL = "http://api.box.com/2.0/folders/0.xml"
Set objHTTP = CreateObject("MSXML2.ServerXMLHTTP")
With objHTTP
.Open "GET", MyURL, False
.setRequestHeader "Content-Type", "application/x-www-form-urlencoded"
.setRequestHeader "Authorization", "BoxAuth api_key=<your api key>&auth_token=<your auth token>
.send (MyURL)
End With
I'll defer to a real VBA expert, but something roughly along these lines should work.

Answer 2

Yeah, this is frustrating. I tried code like Peter's using both WinHttp.WinHttpRequest.5.1 and MSXML2.ServerXMLHTTP and with both I just get a zero-length string back. No error message or anything.
I installed cURL and tested the URL. It works fine there. The script below also works fine with a generic JSON web service, like jsonplaceholder.typicode.com.
All this makes me think that Box.com is receiving the message, detecting it is coming from a non-approved source, and returning nothing . . . probably for security reasons.
Option Explicit
Const URL As String = "https://api.box.com/2.0/folders/0 -H ""Authorization: Bearer MyToken"""
'Const URL As String = "https://jsonplaceholder.typicode.com/posts/1"
Sub Test()
Dim winHTTP As Object
' Set winHTTP = CreateObject("WinHttp.WinHttpRequest.5.1")
Set winHTTP = CreateObject("MSXML2.ServerXMLHTTP")
winHTTP.Open "GET", URL
winHTTP.setRequestHeader "Content-Type", "application/json"
winHTTP.send
Debug.Print winHTTP.ResponseText
If Len(winHTTP.ResponseText) = 0 Then
MsgBox "blank string returned"
Else
Dim objResponse As Object
Set objResponse = JsonConverter.ParseJson(winHTTP.ResponseText) 'Converter from Tim Hall - https://github.com/VBA-tools/VBA-JSON
End If
End Sub