Herby, In Zn #bleedingEdge
=== Name: Zinc-HTTP-SvenVanCaekenberghe.464 Author: SvenVanCaekenberghe Time: 27 July 2017, 1:10:32.048978 pm UUID: 63589259-ac11-0d00-9153-678c0082c0ce Ancestors: Zinc-HTTP-SvenVanCaekenberghe.460 Make ZnSingleThreadedServer>>#start idempotent (since it called #stop and #stop does a #unregister there was a possible side effect, call #stop: false from #start instead) [thx Herby Vojčík] === This still does not solve the core problem of #startUp[:] being called twice (apparently) in some situation. But some extra protection won't hurt. Thx for the suggestion, I hope this solves your current issue (remember to load Zn #bleedingEdge). Sven > On 26 Jul 2017, at 20:19, Herby Vojčík <he...@mailbox.sk> wrote: > > Hi, > > Looking at ZnServer >> start and ZnSingleThreadedServer >> stop (as ZnServer > >> stop is #subclassResponsibility), I had the impression they are meant to > be idempotent. > > The start comment is: > > "Start me. I will start listening on my port for incoming HTTP > connections. > If I am running, I will first stop and thus effectively restart" > > The stop comment is: > > "Stop me. I will stop listening on my port for incoming HTTP > connections. > Does nothing when I am not running" > > So, it seems like both start and stop try to be safe to be sent twice in a > row. > > I did a few Transcript prints: > > --- > > 1. just stop: is ok. > > ZnManagingMultiThreadedServer allInstances do: #stop. > ZnServer managedServers do: #unregister. > Smalltalk garbageCollect. > > (ZnServer on: 4998) stop. > (ZnServer on: 4997) stop; stop. > > Transcript show: ZnServer managedServers; cr; > show: ZnManagingMultiThreadedServer allInstances; cr. > > ==> > > an IdentitySet() > an Array(a ZnManagingMultiThreadedServer(stopped 4998) a > ZnManagingMultiThreadedServer(stopped 4997)) > > --- > > 2. start; stop: is ok. > > ZnManagingMultiThreadedServer allInstances do: #stop. > ZnServer managedServers do: #unregister. > Smalltalk garbageCollect. > > (ZnServer on: 4998) start; stop. > (ZnServer on: 4997) start; stop; stop. > > Transcript show: ZnServer managedServers; cr; > show: ZnManagingMultiThreadedServer allInstances; cr. > > ==> > > an IdentitySet() > an Array(a ZnManagingMultiThreadedServer(stopped 4998) a > ZnManagingMultiThreadedServer(stopped 4997)) > > --- > > 3. register; start; stop: is ok. > > ZnManagingMultiThreadedServer allInstances do: #stop. > ZnServer managedServers do: #unregister. > Smalltalk garbageCollect. > > (ZnServer on: 4998) register; start; stop. > (ZnServer on: 4997) register; start; stop; stop. > > Transcript show: ZnServer managedServers; cr; > show: ZnManagingMultiThreadedServer allInstances; cr. > > ==> > > an IdentitySet() > an Array(a ZnManagingMultiThreadedServer(stopped 4998) a > ZnManagingMultiThreadedServer(stopped 4997)) > > --- > > 4. start: is ok. > > ZnManagingMultiThreadedServer allInstances do: #stop. > ZnServer managedServers do: #unregister. > Smalltalk garbageCollect. > > (ZnServer on: 4998) start. > (ZnServer on: 4997) start; start. > > Transcript show: ZnServer managedServers; cr; > show: ZnManagingMultiThreadedServer allInstances; cr. > > ==> > > an IdentitySet() > an Array(a ZnManagingMultiThreadedServer(running 4998) a > ZnManagingMultiThreadedServer(running 4997)) > > 5. register; start: is not ok. > > ZnManagingMultiThreadedServer allInstances do: #stop. > ZnServer managedServers do: #unregister. > Smalltalk garbageCollect. > > (ZnServer on: 4998) register; start. > (ZnServer on: 4997) register; start; start. > > Transcript show: ZnServer managedServers; cr; > show: ZnManagingMultiThreadedServer allInstances; cr. > > ==> > > an IdentitySet(a ZnManagingMultiThreadedServer(running 4998)) > an Array(a ZnManagingMultiThreadedServer(running 4998) a > ZnManagingMultiThreadedServer(running 4997)) > > The last case is not idempotent for #start. With one #start, the server is > registered, with two #start's, it is not registered. > > Shouldn't the last case be idempotent as well? > > If it is, it is the bug that should be put into issue tracker? > > Herby >
