[Mailman-Developers] Mailing List Subscription Request (fwd)

Gerald Oskoboiny gerald@impressive.net
Wed, 3 Jan 2001 02:26:46 -0500

On Mon, Jan 01, 2001 at 03:38:03PM -0500, Barry A. Warsaw wrote:
> >>>>> "JCL" == J C Lawrence <claw@kanga.nu> writes:
>     JCL> V3 really needs to support something like the following:
>         [ provide URLs for easy subscription confirmations ]
> I completely agree, and, if some of the things I've been playing with
> over the holidays pan out, it'll be easy to add this.

Great... definitely a nice feature.

If you do add this, please make sure the actual confirmation step is
done with an HTTP POST, not a GET, since using GET for this violates
the HTTP protocol (GETting a URL must not have side effects like
confirming an application, only POSTing should.)

So the page displayed at the URL sent by email can display a trivial
HTML form that says something like:

    Confirmation for subscription to list-foo

    [ Confirm ]

where [ Confirm ] causes the form to be POSTed and the subscription
to be confirmed.

(Sorry if this advice seems premature, but I've seen various
similar software get this wrong.)

Further reading on GET vs POST for those who are interested:

    Forms: GET and POST

    Axioms of Web architecture: Identity, State and GET

    HTTP 1.1 section 9.1: Safe and Idempotent Methods

    HTML 4.01 section 17.13: Form submission

Gerald Oskoboiny <gerald@impressive.net>