Feature Enhancement Request: Allow the component to apply custom policy of handling the watch-state of when the switchboard restart

[zhanghuabin]

Hi, Matthias:

I used system-toolbox-* in our online service in past 2 years, thanks for your hard work, your libs are excellent.
But recently I met a little trouble of system-toolbox, please see the background of problem as below:

1. I have a component, which will create some external resources in state-fn.
2. this component has a shutdown-fn as well for closing those external resources when restart the switchboard.
3. and then new external resources will be created in init phase.
4. what I expected is: when the handler of new component receives an event, I can get new resources from current-state.
5. but the actual result is: I get old closed resources now.
6. I have to make a workaround: use @(:cmp-state state) to get the new real current-state of new component
7. these are the timelines when I reproduce this issue.
   
   

Do you have any suggestion better than my workaround in this scene?
Or you may design a mechanism/option to allow the component to controll if they want to reserve the old state or not.

Please keep alive meo and system-toolbox-*, I believe they have many fans. :-)

Thanks a lot
Huabin Zhang

[matthiasn]

Hey Huabin, Great to hear from you and thanks a lot for the feedback. There is an option for not reloading a component but just rewiring the existing one upon system reload. But that could be more fine grained. I’m on my lunch break so I can’t say exactly what the option was, I think :reload false. I’ll have a look after work and get back to you with a more detailed response. What is your service doing? Have a great day, Matthias

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On 11. Oct 2018, at 13:33, Huabin Zhang ***@***.***> wrote: Hi, Matthias: I used system-toolbox-* in our online service in past 2 years, thanks for your hard work, your libs are excellent. But recently I met a little trouble of system-toolbox, please see the background of problem as below: I have a component, which will create some external resources in state-fn. this component has a shutdown-fn as well for closing those external resources when restart the switchboard. and then new external resources will be created in init phase. what I expected is: when the handler of new component receives an event, I can get new resources from current-state. but the actual result is: I get old closed ones now. I have to make a workaround: use @(:cmp-state state) to get the new real current-state of new component these are the timelines when I reproduce this issue. Do you have any suggestion better than my workaround in this scene? Or you may design a mechanism/option to allow the component to controll if they want to reserve the old state or not. Please keep alive meo and system-toolbox-*, I believe they have many fans. :-) Thanks a lot Huabin Zhang — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[zhanghuabin]

Sorry for reply so late, I'm on vacation, ;-)

I apply the Clojure/Script and system-toolkit-* in our two groups of services:

1. A deCAPTCHA service cluster, I define different algorithm as async component, and an individual component for message routing, the cluster is for load-balancing.
2. A whole web app of our internal OA system. For frontend, I refer to your meo project(websocket, reactjs, spa, etc). I use shadow-cljs for building, you may have a try, which is cool.

I knew that :reload option and I have tried, it worked but if we say we must close some resources during the restarting flow, that means we have to realize shutdown fn and enable :reload, that will cause the above problem.

Thanks
Huabin