Legacy Classic ASP / VBScript Support

ASPPY promises 99% compatibility with legacy Classic ASP. It implements a fully functioning VBScript Virtual Machine and provides Python-based shims for the most common built-in ASP objects (Request, Response, Server, Application, Session) and commonly used COM objects.

VBScript Language Features

ASPPY supports standard VBScript syntax and flow control:

Variables & Types: Dim, Const, Variants (Strings, Integers, Booleans, Arrays).
Flow Control: If...Then...Else, Select Case, For...Next, For Each...In, Do...Loop, While...Wend.
Procedures: Sub and Function (including ByRef and ByVal passing).
Classes: Class definitions, Public / Private members, Property Get/Let/Set.
Error Handling: On Error Resume Next, On Error GoTo 0, and the Err object.
Includes:  and .

The Response Object

Used to send output to the client.

Method / Property	Description
`Response.Write(string)`	Writes a string to the HTTP output.
`Response.Redirect(url)`	Sends a 302 redirect.
`Response.End()`	Stops script execution and flushes the buffer.
`Response.Flush() / Clear()`	Flushes or clears the current output buffer.
`Response.File(path, [inline])`	Serves a physical file to the client natively (handles mime type and content length automatically).
`Response.BinaryWrite(data)`	Writes raw binary data.
`Response.ContentType`	Sets the HTTP content type (e.g., "text/html").
`Response.Cookies(name) = value`	Sets a cookie. Supports keys: `Response.Cookies(name)(key) = value` and `.Expires`.
`Response.Status`	Sets the HTTP status line (e.g., "404 Not Found").

The Request Object

Used to retrieve client information.

Collection / Property	Description
`Request.QueryString("key")`	Gets GET parameters.
`Request.Form("key")`	Gets POST parameters.
`Request.ServerVariables("key")`	Gets server vars (e.g., REMOTE_ADDR, HTTP_USER_AGENT).
`Request.Cookies("key")`	Gets cookie values.
`Request("key")`	Shorthand: searches QueryString, Form, Cookies, then ServerVariables.
`Request.Method` / `Request.HttpMethod`	Returns the HTTP method (e.g., GET, POST, PUT, DELETE).

Native File Uploads & Downloads

ASPPY supports native multipart/form-data file uploads via Request.Files, entirely eliminating the need for complex third-party VBScript parser scripts (like freeASPUpload).

<%
If Request.Files.Count > 0 Then
    Dim uploadedFile
    Set uploadedFile = Request.Files("myFile")
    
    If Not uploadedFile Is Nothing Then
        ' Save to disk natively
        uploadedFile.SaveAs Server.MapPath("/data/uploaded_" & uploadedFile.FileName)
        Response.Write "Uploaded: " & uploadedFile.FileName & " (" & uploadedFile.Size & " bytes)"
    End If
End If
%>

Similarly, securely streaming files back to the client is natively supported using Response.File. This stops script execution, handles correct Content-Type guessing, Content-Length calculation, and sets the Content-Disposition automatically.

<%
Dim filePath
filePath = Server.MapPath("/data/download_test.txt")

' The second parameter determines if it's served inline (True) or as an attachment (False)
Response.File filePath, False
%>

The Server Object

Method	Description
`Server.CreateObject(progid)`	Instantiates COM objects (shimmed by Python equivalents).
`Server.MapPath(path)`	Translates a virtual path to a physical filesystem path.
`Server.HTMLEncode(string)`	Encodes HTML characters.
`Server.URLEncode(string)`	URL-encodes a string.
`Server.Execute(path) / Transfer(path)`	Executes another ASP page.

Supported COM Objects via Server.CreateObject

ASPPY intercepts Server.CreateObject calls and routes them to native Python implementations:

Scripting.Dictionary - Native dictionary implementation with string/case-insensitive mapping.
Scripting.FileSystemObject - Native file IO (File, Folder, TextStream).
ADODB.Connection, ADODB.Recordset, ADODB.Command - SQL database connectivity.
ADODB.Stream - Binary and Text stream manipulation.
VBScript.RegExp - Regular expressions (powered by Python re).
MSXML2.ServerXMLHTTP / MSXML2.DOMDocument - HTTP requests and XML parsing.
CDO.Message - Email sending.