Re: [Gnumed-devel] gmPG2

[syan tan]

You are very right , after thinking about it. After login,
my web app wouldn't be able to keep the connection object
around, unless I knew the apache implementation was
single threaded, or multithreaded with a non-threaded object
area ,  so I need to save the dsn, and recreate the connections
for each query on the backend ! Maybe need to wrap the business
stuff as a real server process then, and maybe do pre-initialized
multiple business servers, that store login identities as tokens, 
just like apache multi-process !
  What a headache!

On Mon, 2007-02-05 at 09:20 +0100, Karsten Hilbert wrote:
> On Mon, Feb 05, 2007 at 08:57:52AM +0800, Syan Tan wrote:
> 
> > if a get_connection call succeeds with a dsn,
> > is that added to the pool, and then business objects
> > will find it, or does a handle to the conn object have
> > to be passed somewhere ?
> 
> The get_connection() returns a connection authenticated for
> the DSN passed in or for the DSN set as the default.
> 
> Eventually, I want to add pooling the connections so that
> when get_connection() is called with pooled=True it will
> return a connection from the pool - if one is available for
> the DSN. I have not gotten around to figuring out all the
> details (thread safety etc). The external interface won't
> change, however: 
> 
>  conn = gmPG2.get_connection(...)
>  curs = conn.cursor()
> 
> So, yes, you will have to pass in the connection to the
> business objects.
> 
> However, since that would be very cumbersome, you can also
> set a default DSN to use for connections and call methods
> which require a <link_obj> parameter (such as
> gmPG2.run_ro/rw_queries()) with a value of None. They will
> then get their own connection from gmPG2 with the previously
> set default DSN. This will start a lot of connections and
> for that pooling should help tremendously. If you can help
> me to figure out how to safely enable pooling I'd be
> delighted to add it in.
> 
> BTW, thos <link_obj> parameters can take None, a connection,
> or a cursor, for convenience.
> 
> Karsten