Public Sub RefreshFilms()
    Dim http As Object, url As String, json As String
    Set http = CreateObject("MSXML2.ServerXMLHTTP.6.0")

    url = "https://crowdata.ca/excel-demo/data.php"
    If Range("CategoryFilter").Value <> "" Then
        url = url & "?category=" & UrlEncode(Range("CategoryFilter").Value)
    End If

    http.Open "GET", url, False
    http.Send
    json = http.responseText

    ' Parse JSON, populate the Films sheet, refresh pivots
    PopulateFilmsSheet ParseJson(json)
    ActiveWorkbook.RefreshAll
End Sub