feat(hydrated_bloc): Isar instead of Hive for storage

[ac130kz]

Description

Hive has an issue with high RAM usage, no support for queries and less than desirable performance for complex data [1], which in my opinion fits the purpose of hydrated_bloc. Recently a complementing library to solve these issues from the same author (@leisim) got released into stable, and it's called Isar [2]. For now, it comes with two primary downsides: it is still quite young, the web support is to (soon™).

Desired Solution

Hive is replaced with Isar as the main means of dealing with cached storage within hydrated_bloc.

Alternatives Considered

Hive alternative Objectbox [3] is not written in Rust (unlike Isar), thus any memory, undefined behaviour and concurrency related bugs will be present in higher amounts and will be harder to spot even for experts since it's inherently harder to setup for safe reliable code. However, it comes with a variety of interfaces to other languages, e.g. Kotlin and Swift.

Additional Context

[1] isar/hive#246
[2] https://github.com/isar/isar
[3] https://github.com/objectbox/objectbox-dart

[felangel]

Hi @ac130kz 👋
Thanks for opening an issue!

I'll take a closer look at Isar now that it's stable to evaluate if it makes sense to make this transition.

My initial reaction is to compare performance between Hive and Isar (are you aware of any official benchmarks?) and to create a small p.o.c.

My main concern is it looks like Isar doesn't support web whereas Hive does. Also, Isar relies on code generation so hydrated_bloc would likely also require developers to run build_runner which is a disadvantage when compared to Hive in my opinion.

I'll drop some more thoughts/comments once I've taken a closer look at Isar and the level of effort to migrate to it but feel free to add your thoughts in the meantime, thanks! 🙏

[ac130kz]

@felangel
I guess as a temporary performance measurement Objectbox's benchmarking suite can be updated to support the latest version of Isar [1]. As for the build_runner, I think it might not be such an issue, fingers crossed static metaprogramming in Dart will help in this regard within a couple of months [2].

UPD: found a mention of preliminary benchmarks by @leisim on Reddit [3].

[1] https://github.com/objectbox/objectbox-dart-performance
[2] dart-lang/language#1482
[3] https://www.reddit.com/r/FlutterDev/comments/rti7sk/stable_version_of_isar_database/hqt6geg/

[felangel]

@felangel I guess as a temporary performance measurement Objectbox's benchmarking suite can be updated to support the latest version of Isar [1]. As for the build_runner, I think it might not be such an issue, fingers crossed static metaprogramming in Dart will help in this regard within a couple of months [2].

UPD: found a mention of preliminary benchmarks by @leisim on Reddit [3].

[1] https://github.com/objectbox/objectbox-dart-performance [2] dart-lang/language#1482 [3] https://www.reddit.com/r/FlutterDev/comments/rti7sk/stable_version_of_isar_database/hqt6geg/

That still doesn't address the lack of web support and I agree that static metaprogramming will likely help with codegen; however, it feels premature to make this change given the current state of things. I think it'd be nice to revisit this in a few months.

[PawlikMichal25]

Isar now supports Web https://pub.dev/packages/isar/changelog#220
but I also think it's still too early 😛

[cofirazak]

Is there any news about this thread?

[anlumo]

Isar FAQ:

Isar vs Hive

The answer is easy: Isar was started as a replacement for Hive
and is now at a state where I recommend always using Isar over Hive.

[maximveksler]

Isar FAQ:

Isar vs Hive

The answer is easy: Isar was started as a replacement for Hive
and is now at a state where I recommend always using Isar over Hive.

Which contridicts with

(src isar/hive#246 (comment))

[Gene-Dana]

Where you start and where you end up are not always the same place !