Question about saving a loaded model to the database

[XaelZeph]

Hello, I am currently trying to save a loaded model (it has a few steps through it, I want to save the state) in a database, then return to it. See the python code (which load_model and runs model.do_step) is being called by another program, which closes the python code afterwards. I need to be able to save the state of that model so the next time the prgram called the python code and runs model.do_step, previous data is saved. I'm using db.sqlite3 as my backends database.

I heard that pickling or JSON-Encoding may allow a FMUModel to be saved in the data base as a Json string, but I'm not sure if that would work. Any thoughts/comments?

[XaelZeph]

I have the database and API already set up, I'm just stuck on how to turn a python object into something sqlite3 will take.

[PeterMeisrimelModelon]

Hi,

what you are looking for is this: https://fmi-standard.org/docs/3.0/#get-set-fmu-state (same principle thing for FMI2)

Relevant PyFMI functions here are:

get_capability_flags # to check if your FMU(s) actually support this.
get_fmu_state
set_fmu_state
free_fmu_state
serialize_fmu_state
deserialize_fmu_state

/Peter

[XaelZeph]

What flag do we need to check? Is it "canRunAsynchronuously", "canSerializeFMUstate", or "canNotUseMemoryManagementFunctions". I see that there's also "canGetAndSetFMUstate" for the get/set for the fmu state.

If these are false, is there any other way to support this?

[PeterMeisrimelModelon]

canGetAndSetFMUstate is required for get_fmu_state and set_fmu_state.

canSerializeFMUstate for serialize_fmu_state, deserialize_fmu_state to be able to translate the save state to a byte sequence for e.g., storage.

If these are not supported, this might not be possible/feasible. From your original question, I take it this is about CS FMUs?
Might be worth it to raise this question at the source/tool that generates your FMUs.

/Peter