RFC: mysql-native - Supporting both Vibe.d and Phobos sockets

[Nick Sabalausky]

On Tue, 14 May 2013 15:37:50 -0400
Nick Sabalausky <SeeWebsiteToContactMe at semitwist.com> wrote:

> On Tue, 14 May 2013 04:35:20 +0200
> "Nathan M. Swan" <nathanmswan at gmail.com> wrote:
> 
> > preclude a design like this?
> > 
> > -----
> > interface MysqlSocket {
> >      // ...
> > }
> > 
> > class PhobosSocket : MysqlSocket {
> >      this(std.socket.Socket _backend) {
> >          // ...
> >      }
> >      // ...
> > }
> > 
> > class VibeSocket : MysqlSocket {
> >      this(vibe.core.net.TCPConnection _backend) {
> >          // ...
> >      }
> > }
> > -----
> > 
> 
> That's actually somewhat similar to what I ended up doing internally:
> I created a minimal wrapper for std.socket.Socket to expose a
> vibe-like socket API (but only for what's actually necessary for
> mysqln, nothing more, so it isn't a general, full-fledged
> phobos->vibed socket adapter). Then, based on how the templates are
> instantiated, the socket will be typed as either
> vibe.core.net.TCPConnection or the internally-defined phobos socket
> wrapper. I had some reasons for doing it that way, however...
> 
> However, now that you mention it, I think you're right, I should be
> able to just add a trivial pass-through wrapper for Vibe.d's sockets,
> define a minimal common interface for that and the Phobos socket
> wrapper, and just pass that interface into Connection.this().
> 
> There were some reasons I didn't go down that route before, but now
> that I think about more, I don't think those reasons were valid. And
> this definitely leads to a much cleaner design and API, plus it's more
> powerful (can use subclasses of either socket type). And while virtual
> method invocation isn't free, it should be completely negligible
> compared to actually performing network I/O, even if it's just
> localhost.
> 
> I'm going to try that, see how it plays out.
> 

Hmm, there is a problem: For Vibe.d, mysql-native's Connection class
is expected to derive from EventedObject. But EventedObject is part of
Vibe.d. I'm not sure offhand how to handle that without making
mysql-native's Connection templated.