If I need to use cookies, would it make sense to keep a ZnUserAgentSession and assign it to each new client?
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. 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 >> >
