> On 1 Nov 2021, at 20:03, Esteban Maringolo <emaring...@gmail.com> wrote:
>
> If I need to use cookies, would it make sense to keep a ZnUserAgentSession
> and assign it to each new client?
I don't know or remember, my first reaction would be to say that it was not
designed for that purpose, but maybe it could be used for that.
> I'm asking this in case I have to share cookies between requests. But the
> session variable seems to be private in ZnClient given that it doesn't
> provide any setter.
There is the cookie jar object inside the session, maybe you can try to share
that ?
Or you could copy the necessary cookies over ? That certainly seems like the
safest thing.
> Regards,
>
> Esteban A. Maringolo
>
>
> On Mon, Nov 1, 2021 at 1:39 PM Esteban Maringolo <emaring...@gmail.com> wrote:
> Thank you Sven.
>
> I'll go with instantiating a new client for each request, the less state
> shared, the better :-)
>
> Regards!
>
> Esteban A. Maringolo
>
>
> On Fri, Oct 29, 2021 at 12:15 PM Sven Van Caekenberghe <s...@stfx.eu> wrote:
> Hi,
>
> > On 29 Oct 2021, at 15:42, Esteban Maringolo <emaring...@gmail.com> wrote:
> >
> > Hi,
> >
> > I happened to me more than once that I have to create some REST service
> > "client" in which I usually wrap an HTTP client inside (ZnClient in this
> > case), and all the calls to the service, end up using the HTTP client,
> > inside some mutex to serialize the execution.
>
> Yes, that is a good design. However, whether your REST client object wrapping
> a ZnClient is used by multiple concurrent threads is another decision. I
> would personally not do that. See further.
>
> > But I don't like that, in particular when some endpoints are better with
> > streaming responses (large downloads) and I have to fiddle with the client
> > and set it back to the settings before executing the request.
>
> You only can and should reuse connections to the same endpoint/service only,
> doing similar types of request/responses (let's say simple ones).
>
> A definitive danger point is authentication and authorization: different
> calls by different users might need different REST call settings, each time.
> Also, caching can be a problem, if user A can see / sees the cache of user B.
>
> > So, long story short... is it always safer to instantiate a new ZnClient on
> > a per request basis since no state is shared, but I guess it is also less
> > effective if I'm performing several requests to the same server.
>
> A new instance is definitely safer because it is cleaner. Reusing a
> connection is more efficient when doing multiple calls in (quick) succession.
> The penalty is usually pretty low, you can postpone optimising until there is
> an actual problem.
>
> Error handling and recovery are also harder in the reuse case (what state is
> the connection in ?).
>
> ZnClient does a form of automatic reconnection/retry though.
>
> > What are the recommended approaches here?
> >
> >
> > Esteban A. Maringolo
>
> HTH,
>
> Sven
