chestdb / chest

A type-safe, pure-Dart in-memory database with amazing developer experience.

⚠️ This package is in its alpha stage. You can use it experimentally, but not in production yet. The binary format is not stable yet, so data might be lost. Stay tuned!

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A type-safe in-memory database with amazing developer experience.

documentation · examples · how it works · FAQ

What's a database? It's just a place where you can persist data beyond your app's lifetime. Chest offers exactly that: persistent variables called chests.

var counter = Chest<int>('counter', ifNew: () => 0);
await counter.open();
print('This program ran ${counter.value} times.');
counter.value++;
await counter.close();

But isn't treating databases like variables inefficient? Not at all! To be clear, you don't need to read or save the whole object every time you make a change. Chest allows you to only change part of a value, even fields marked with final.

var me = Chest('me', ifNew: () => User());
await me.open();
me.value; // Decodes the whole user.
me.pet.value; // Only decodes the pet.
me.pet.favoriteFood.color.value = Color.red; // Only changes the color.

The important thing is that me is not a User, but a Reference<User>. Only when you use the .value getters or setters, you actually decode or change a subtree of the data.

This is especially handy if you're dealing with large maps:

var users = Chest<Map<String, User>>('users', ifNew: () => {});
await users.open();
var marcel = users['marcel'].value; // Only decodes Marcel.
users['jonas'].value = User(...); // Only saves Jonas.

Hang on. How does Chest know how to handle my types? Chest comes with its own encoding called tape. Some types already have built-in tapers (serializers for objects). You can annotate your types with @tape and let Chest generate tapers automatically:

// Run `dart pub run build_runner build` in the command line.
part 'this_file.g.dart';

@tape
class Fruit {
  final String name;
  final Color color;
}

Other perks

• ❤️ Amazing developer experience. Just like you can inspect your program with Dart's DevTools, you can inspect, debug, and edit your database with ChestTools live in your browser.
• 🎈 Lightweight. Chest is written in pure Dart and has no native dependencies. That means it works on any platform.

Intrigued? Here's how to get started.

chest's Issues

Set up chesttools

Similar to Dart's DevTools, ChestTools should allow inspecting and debugging the Chest database.

Rename

The name "Cassette" is long, difficult to spell correctly (even I had to look it up), and difficult to say quickly. It's a cool reference to Tape, but this package isn't even tightly coupled to Tape, so I'd rather opt for a short, one-syllable name like "Chest".

Use execution_queue for transactions