PocketIC: Multi-Subnet Canister Testing Today, we released PocketIC v2.0.0, which enables canister developers to test in a multi-subnet setting. The new server version comes with matching updates to the Rust library and the Python library . Multi-subnet testing is a novelty in the ecosystem, so cons…

[image] fxgst: may I ask why you’re executing these calls? In my case, I’m executing it at the start of most of the test functions in ic-websocket-cdk-rs integration tests , so that I can test each method of the CDK separately. So, I basically use the reinstall_canister function as a way to re…

Hi @ilbert , to mute all messages from the server, you can set the env variable POCKET_IC_MUTE_SERVER=1. The “No state available with certification” can safely be ignored. It is printed by the state machine when executing the first round since we don’t certify states for testing.

I think you could also create a new canister in order to reset it’s state. I believe this should be faster than deleting, ticking and reinstalling it, but I haven’t tested it myself.

[image] fxgst: create a new canister This doesn’t make much difference for my tests, so I opted to another solution: using a custom wipe method on the canister to reset its internal state. This way I use the the same canister across all tests and I don’t have to install a new one each time.

[image] michael-weigelt: Therefore, be extra careful with timers/heartbeats, which are and always have been only tentatively supported by PocketIC. Is there a reason why now timers are not working anymore only in a Motoko canister? Should I add more ticks?

Hi ilbert, Are you saying your timers have worked before and now don’t?

Yes, that’s the behavior I’ve observed. Adding 100 ticks (instead of just 1 as I was doing with PocketIC v1) after advance_time seems to solve it.

If there are crossnet calls involved, I may have an explanation. Think of a tick as a round of ticks for every subnet. The round always happens in the same order, so if you have an xnet call from a canister in subnet 2 to a canister in subnet 1, then the xnet call will take two rounds to be process…

There are no crossnet calls involved, I just had to add the NNS subnet in order to be able to call the root_key method. The canister I’m testing is anyway deployed on an app subnet. [image] michael-weigelt: In any case, since PocketIC is deterministic, you may want to figure out how many ticks …

PocketIC: Multi-Subnet Canister Testing

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michael-weigelt May 3, 2024, 4:21pm 28

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PocketIC: Multi-Subnet Canister Testing

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