While there are a lot of changes, the most significant are:
- Update the main entrypoint of the SDK to use a suspending function and eliminate lazy initialization. This also resolves#310
- Changing Dao methods to `suspend`, allowing Room to implicitly manage the threading model under the hood
- Explicitly set the executor thread for the `CompactBlockDb` and `DerivedDataDb`, which is the same thread used when calling into the Rust native library. Room will then use this thread for `suspend` fun calls into it
- With the above set, remove unnecessary hops to Dispatchers.IO which is a thread pool
- Eliminate lazy initialization in `PagedTransactionRepository` to make it easier to reason about the threading model and resolve#355 where the database was being touched from the UI thread
Note that `PendingTransactionsDb` is not opted into this single-threaded approach, because that database is not shared with the Rust code
The synchronizer now primarily collaborates with a downloader, processor and repository; each with a more focused set of responsibilities.
The downloader streams blocks into a channel, the processor saves blocks from that channel and scans for transactions, the repository
exposes transaction change events.
Previous version did a bad job of recognizing an incorrect config file.
This makes it a bit better. It also removes the need for a config in the
parent directory.
Co-authored-by: Jack Grigg <jack@z.cash>