Hi! I agree that users shouldn't expect a non-proxy when invoking the `IgniteServices#serviceProxy()` method. I think it's up to Ignite to return a non-proxy instance here as possible optimisation. But users have to use interfaces in any case. There is the `IgniteServices#service()` method for explicit return of local instances.
With enabling of metrics we can break users that explicitly use `#serviceProxy` (proxy!), and then explicitly cast it to an implementation class. In this case such users will get a runtime exception. I think we can write a good javadoc for `ServiceConfiguration#setEnableMetrics()`, it should mention that it works only with proxy, and it doesn't collect metrics with non-proxy usages with `IgniteService#service()`. So, I propose to proceed with two solutions - 1 and 3: fix docs for `#serviceProxy()` and provide detailed javadocs for `ServiceConfiguration#setEnableMetrics()`. If some users will enable metrics (even with such docs!) and will be using casting proxy(!) to an implementation, then they will get a runtime exception. But I believe that it is an obvious failure, and it should be fixed on the user side. On Mon, Dec 27, 2021 at 10:26 PM Vladimir Steshin <vlads...@gmail.com> wrote: > Hi, Igniters. > > > I'd like to suggest modifying `/IgniteServices.serviceProxy(String name, > Class<? super T> svcItf, boolean sticky)/` so that it may return proxy > even for local service. Motivation: service metrics [1]. To measure > method call we need to wrap service somehow. Also, the method name says > `proxy`. For local one we return direct instance. Misleading. > > > Solutions: > > 1) Let’s return a proxy (`/GridServiceProxy/`) once we need. Let’s > change the javadoc to say `@return Proxy over service’. Simply works. > > Pros: invocation like `/MyServiceImpl svc = serviceProxy(«myservice», > MyService.class)`/ would fail. Wierd usage to me. But possible. > > 2) Introduce a new method with forced-proxy flag > like`IgniteSerives.serviceProxy(…, boolead focedProxy)`. And add a > warning to other service-obtain methods like: «`/You enabled service > metrics but it doesn’t work for local service instanse. Use forced-proxy > serviceProxy(…, boolean forcedProxy)/` Pros: we’ve already have about > 5-6 methods to get services in `/IgniteServices/`. I doubt we need one > more. > > 3) Fix the documentation so that it tells the service metrics would work > only with proxy. Pros: service metrics just won’t work for local > services. Suddenly. > > > My vote is for #1: let's use a proxy. WDYT? > > > [1] https://issues.apache.org/jira/browse/IGNITE-12464 > >
