RC is a configuration/collection manager that uses . (dot) to set and read collection contents. And it is designed with loaders to load collections from various locations such as environment variables.

RC's name uses the acronym of Runtime Configure/Real Collection. You can use it as a collection container, and you can also use it as a configuration manager with a loader.

What is a collection? Collection is a concept, usually Map/List/Set/Iterable are all collections.

Use command line:

dart pub add rc

Or update your pubspec.yaml file:

dependencies:
rc: latest

import 'package:rc/rc.dart';

final config = RC(init: {
    'app': {
        debug: true,
    }
});

// A more concise approach 👇
// final config = RC(init: {'app.debug': true});

print(config('app.debug')); // true

Parameters:

To get data, we use the call method. Usually you can ignore it. You can use the created RC instance in a similar way to function call:

final value = config('app.debug');

It also has a type parameter T, which can tell the getter what data type you expect:

final debug = config<bool>('app.debug');

Note: If the app.debug data type is not bool, it will return null. If shouldWarn is configured as true, a warning message will be printed in the console.

In addition to getting specific values, you can also get collection values ​​with Map<String, dynamic> type:

final app = config('app'); // {debug: true}

Setting a value usually uses the set method, which can update a specific value or set a new collection:

// Sets a value
config.set('app.debug', 1);

// Sets a collection
config.set('user.profile', {
    'id': 1,
    'name': 'Seven',
});

Collection values ​​also support . connected collections, or a mixture of Map/Set/List/Iterable and . collections:

config.set('app.user', {
    id: 1,
    'emails.0': {id: 1, validated: true},
    'prifile': {
        'id': 1,
        'posts': [
            {id: 1, title: 'First post'},
            {id: 2, title: 'Post 2'},
        ],
    },
});

In short, you can combine collection types in any way you want.

Updating a value or collection is usually a syntactic sugar for the combination of call and set, which allows you to get the previous data for processing before updating the value:

config.update<bool>('app.debug', (prev) {
if (prev == true) return prev;
    return false;
});

To delete a value or collection, use the delete method:

// Delete a value
config.delete('app.debug');

// Delete colection
config.delete('app');

To determine whether a value or collection exists, you should use the contains method:

config.contains('app');
config.contains('app.debug');

Loaders are used to load collections from other places into RC, such as dart --define or environment variables.

There are two ways to configure loaders. The first is to set loaders when creating RC. You can also use use to configure loaders after creating an RC instance:

config.use(const DefineLoader());

Built-in loaders: