Persister test suite for testing redb persister

[casey]

@raphjaph and I are writing a persister implementation for redb.

Is there an existing test suite we can use to test our persister, to make sure that it works?

[notmandatory]

Thanks for working on this, was on my TODO list. We have our current wallet persistence tests (mainly sqlite) here:

https://github.com/bitcoindevkit/bdk/blob/master/crates/wallet/tests/wallet.rs

[casey]

It would be super nice if we could just plug in our persister and have it run against the suite. (Or write a small new test which invoked the suite with our persister.)

Writing a non-performant persister is very easy, just apply and save the new changeset as a single serialized JSON or CBOR value. But I think if we try to make it fast we'll run into a bunch of weird edge cases.

[notmandatory]

I'd suggest at least storing keychain_txout::ChangeSet in it's own table since it needs to be updated every time a new descriptor index is revealed and should be committed before letting the user see a new deposit address. For the rest it would be nice to roughly follow the table schema we're using for sqlite, but I haven't thought too deeply about how that would work.

[pingu-73]

hi @casey @notmandatory i was trying to add redb as a storage back-end for bdk wallets i've created a basic implementation that stores the entire changeset as a serialized JSON value in a single table and have written some basic tests that verify it works for creating and loading wallets.
my current approach:

• uses a single table with a key-value structure
• serializes/deserializes the entire ChangeSet as JSON
• implements both WalletPersister and AsyncWalletPersister traits
• includes basic tests for creating/loading wallets

my implementation can be found here: redb_wallet_storage

Have you folks made any progress on a redb persister implementation, or do you have any guidance on how I should proceed with this approach?

[casey]

Hi @pingu-73! We've done the very basics, I think very similar to your approach. We haven't gotten fancier. In particular, before we get fancy, we would need to either write our own comprehensive test suite, or be able to reuse the tests from bdk, which is difficult at the moment.

[110CodingP]

@casey will extracting out the unit tests in the bdk_redb persitence crate and making them generic over a WalletPersister impl serve your use case?

[casey]

Yup, that would be a great approach, although our work to replace Bitcoin Core with BDK has stalled, and I'm not sure when we'll pick it back up again.