Ideas for VSGI (before it's too late)

[arteymix]

I have two idea that could change quite a lot VSGI design:

• cancellabe API
• return value for ApplicationCallback

The cancellable API would provide the capability to the server to literally cancel a dispatched request processing. http://valadoc.org/#!api=gio-2.0/GLib.Cancellable

In short, if a client connection closes before time, we could cancel the whole process gracefully.

The return value for ApplicationCallback would let the caller know if the request has been or will eventually be handled (asynchronously). For Valum, it is a very interesting change because we could simply return the next callback:

app.get ("", (req, res, next) => {
    if (authenticated (req))
        return next (req, res);
    throw new ClientError.NOT_AUTHORIZED ("");
};

However, these two changes would affect the APIs quite drastically. The cancellable can be implemented in the Request or Response object.

[arteymix]

FastCGI can abort the request: http://www.fastcgi.com/devkit/doc/fcgi-spec.html#S5.4

[arteymix]

I introduced two changes related to VSGI:

• head is written on disposal of the response
• Response.get_body_async for convenience

[arteymix]

I merged the return value and it's really awesome:

• no more 404 at the bottom of perform_routing (consistent handling)
• OPTIONS can produce an Allow header even if no route is matched
• Route like the one created by use are not producing their matched methods

The cancellable API and I/O priority could be part of the context.

[arteymix]

We don't really need a cancellable/priority API since this is something we would rather do specifically.

Returning a boolean value from the callbacks was a very elegant solution for the continuation-passing style.