Persistence as a permanent feature

[wols]

I'm currently working on an app where the statemachine is controlled via (cliff) CLI.
It's my first use of python-statemachine: The commands steer the continuation to the finale.

Currently I believe it is imperative to save state (after transitions) between CLI commands.

Issue #358 and issue358_persistence.md seems to pave the way there?

[fgmacedo]

Hi @wols, I think they're good starters. It depends on your use case and on how you plan to persist the state. But the example is a good starting point as it introduces a generic approach that can be customized with concrete solutions.

I've written an example in the gallery based on the #358 issue: https://python-statemachine.readthedocs.io/en/latest/auto_examples/persistent_model_machine.html

Do you have a specific question or proposal?

[fgmacedo]

@wols closing for now, feel free to reopen or ask any other questions.

[chayim]

@fgmacedo @wols , I just build a state machine for redis, and was looking to connect it to this project, and see what we can learn! In fact, all of our tests are written in python.

Can I maybe have your feedback.. and help? I'd love to know what would be useful, what might be missing, etc? I was about to introduce a docker, to make exploration easier. Would you be interested in working together? I think the speed and lightweightedness of Redis makes this a perfect source or these things.

[fgmacedo]

Hi @chayim, thanks for getting in touch. How are you?

Looks promising, I'll take a closer look soon. I didn't get how actions could be performed as the events and transitions will run on Redis. Do you have a plan for this?

What comes to my mind is that you already contributed by giving an idea:

I've written an example in the gallery based on the #358 issue: https://python-statemachine.readthedocs.io/en/latest/auto_examples/persistent_model_machine.html

We can have a custom persistence class that is powered by Redis :)

[chayim]

Hi @chayim, thanks for getting in touch. How are you?

@fgmacedo I'm doing great my friend, and you?

What comes to my mind is that you already contributed by giving an idea:

I'm excited to collaborate on this! So - my initial thoughts involved plugging state machines into our programmable framework, RedisGears. We could do all sorts of really interesting things like trigger state machine migrations (or ) based on key changes. This was my first order thought - and your domain model is really interested!

I'm just tagging in @MeirShpilraien so that he can see what we're thinking. It sounds like you'd be open to a custom persistence class...

[fgmacedo]

@fgmacedo I'm doing great my friend, and you?

It's great to hear that you're doing well, my friend! As for me, I'm doing pretty well too, thanks for asking.

Nice, I'm not sure how to contribute yet, but please let me know and feel free to ask anything :)

[chayim]

@fgmacedo Maybe I'm overcomplicating things. But in the basic case, it would seem to me that the right answer instead it to extend the StateMachine class with a StateMachine, then in that case, implement the on_transition. Similarly, by overrideing init and del the other sides of state machine initialization (on the remote) could happen.
WDYT?