gistfile1.txt

' Add the necessary references to your VBA project:
' - Microsoft XML, v6.0
' - Microsoft Scripting Runtime

Public Function Base64Encode(text As String) As String
    Dim arrData() As Byte
    arrData = StrConv(text, vbFromUnicode)
    Dim objXML As Object
    Set objXML = CreateObject("MSXML2.DOMDocument.6.0")
    Dim objNode As Object
    Set objNode = objXML.createElement("b64")
    objNode.DataType = "bin.base64"
    objNode.nodeTypedValue = arrData
    Base64Encode = objNode.text
    Set objNode = Nothing
    Set objXML = Nothing
End Function

Public Function GetOAuth2TokenWithPassword(clientId As String, clientSecret As String, tokenUrl As String, username As String, password As String) As String
    Dim http As Object
    Dim json As Object
    Dim jsonConverter As New JsonConverter
    Dim payload As String
    Dim responseText As String
    Dim token As String
    Dim authorizationHeader As String