Broadcast an event to all instances of an Addin/Extension

[Ian Mitchell]

I have an addin which is used by both a model manager - for doing important changes to some model rules - and by regular modellers.
For performance reasons, whist the modellers are working they use a cached version of the rules (there are lots) but I need a way for the model manager to force every active instance of the addin to refresh it's copy of the rules. (when a modeller restarts EA it will refresh anyway - but this is for those bad people like me who have EA open 24/7)
A perfect solution would be for model manager's instance of the Addin to create an event, which is then picked-up by all the other instances, but there doesn't look to be such a thing.
Another solution would be to have a place in the model where the manager instance can write data, which could then be constantly examined by the modeller instances for any changes, but that would be building a performance bottleneck. And rubbish.
Has anyone solved this ?
Thanks

[qwerty]

You (more or less) can't solve that. EA uses a DB to query it, but does not receive events. You "might" set up a framework to communcate concurrently from your add-in (via whatever message queue you prefer) and do tricky things you need. I guess that would be possible. But definitely a lot of work.

q.

[Geert Bellekens]

I did something similar for my EA-Matic scripts.
If someone updates the scripts in EA, I would have liked all the other users of the add-in to get notified, so the scripts could be refreshed.

Since that was not possible (the update of scripts doesn't event trigger any events, so my add-in is not aware of any) I added a check to validate if any of the script had changed. This check is performed on any of the broadcast events, if the previous check was more than 5 minutes ago.

So effectively, a change to an EA-Matic script is being propagated to all users within 5 minutes. (you can still trigger a refresh manually by opening the settings window)

What I did in order to validate if anything had changed, is to store the hash of all scripts together in memory.
Then when I check again, I make a new hash, and compare that to the hash in memory.

I guess you could do something similar. Every 5 minutes or so make a hash of all your rules, and compare that to the previous one. If there is a difference you know you need to refresh the rules.

If you control the changes from within the add-in, you can set a flag somewhere in the database to indicate that you've changed the rules. If you use a new GUID each time you update the rules, the running instances can check that GUID against the one that is loaded. If it's different, they need to refresh.

Geert

[Ian Mitchell]

Thanks Geert/Q - I was just checking I didn't miss something.
I'll pass this along to my customer, and see if they like it. I'm always nervous about solutions like this, where lots of clients are regularly  reading a single part of the model..(I like your 5-minute check - i should reduce the volume a lot)
Thanks guys.