Dime is Dart Dependency "injection framework", it is more like factory and static lookup but with nice wrap.

Dime allows to create modules that define injection types and their InjectFactory implementations. It can easily base on interfaces which allows to pick different implementations. Supports for tag tag based same type instances. Support for multiple modules and scopes with Closable interface to cleanup resources.

Get it from pub page: Pub dime page

Note: All examples below are from example file file. Go there for high level view.

Usage

A simple usage example:

import 'package:dime/dime.dart';

void main() {
  /// Service Module does include details how to create the objects.   
  dimeInstall(ServiceModule());
     
  MyTitleService titleService = dimeGet();
  // or 
  var titleService = dimeGet<MyTitleService>();
  print(titleService.text());
  
}


Setup

Add package dependency to pubspec.yaml:

 depedency: 
   ...
   dime: ^0.4.0
   ...

Define module:

Create a module and how it creates its dependencies:

class MyModule  extends BaseAppgetorModule {
    @override
    void updateInjections() {
        /// define injection factories - below for examples      
    }
}

Below are examples that can be used inside updateinjections method.

Singleton per type

get single value by its class type:

  addSingle(MyTitleService());

get singleton value by implementing interface:

  addSingle<TitleService>(MyTitleService());

Singletons per type with tag

get single value by its class type:

  addSingle(MyTitleService(), tag: "home-title");
  addSingle(MyTitleService(), tag: "details-title");

get singleton value by implementing interface:

  addSingle<TitleService>(MyTitleService(), tag: "home-title");

Creator on-demand injection, it uses type of Creator

This is creator - which will create an object at time of injection.

typedef Creator<T> = T Function(String tag);

The Creator provides optional String tag that may be used to create the tagged instance.

addCreator<TextService>((tag) =>
        MyTitleService(title: "Test title: $tag: now: ${DateTime.now()}"));

Async Creator on-demand injection with Future value

We can make the Creator function to return Future:

addSingleByCreator((tag) async {
      return Future.delayed(Duration(seconds: 2), () {
        return My2TitleService();
      });
    });

With this setup we can use new method to fetch Future of the value:

var value = await dimeGetAsync<My2TitleService>();
// or
My2TitleService service;
/// (some code)
service = await dimeGetAsync();

or old style which was always supported

var value =await  dimeGet<Future<My2TitleService>>();

The dimeGetAsync helps to cast to known type without defining type in < >

Creator on-demand injection with singleton storage - delayed singleton.

Similar to above example with addCreator, however created instance will be cached per tag.

addSingleByCreator((tag)=>MyDescriptionService());

Create your own factory.

You can always create your own factory by extending getFactory<T> and add those to the module.

 addFactory(MyTooltipService, MyCustomFactory());

Note: There are some other Factories already provided to be used - like:

  • getTagFactory for create method with a Tag
  • TaggedSingletongetFactory - for tagged singletons with Closeable interface
  • SinglegetFactory - single get factory with Closable interface

Add modules to the scope (global too)

You can add modules to the main global scope of Dime or into the opened scopes. When a scope closes all modules in that scope will also close (clean up) by calling each of its Closeable factory close() method to cleanup resources.

Add Module to Global Dime scope.

  dimeInstall(ServiceModule());

Dime Scope fetch up the tree examples:

Test class to be referenced by main scope_test.dart tests.

Modules:

ModuleInstance
ModuleAAA()
AB()
AC()
ModuleBBA()
BB()
BC()
ModuleCCA()
CB()
CC()
ModuleXXAA()
BB()
CC()

Scope graph:

Root ScopeModules/ScopesModules/ScopesModules/Scopes
Dime- ModuleC
- ModuleXX (override)
- scope1- ModuleA
- ModuleB
- scope2- ModuleA
- ModuleC
- scope 21- ModuleC
- scope 22- ModuleA
- ModuleB

Example injections:

scope2.inject -> from scope2.ModuleC.CA

Dime.inject -> from dime.ModuleC.CA

scope1.inject -> from dime.ModuleC.CA

scope1.inject -> from scope1.ModuleA.AA

scope2.inject -> not found - can't access other scopes

scope2.inject -> from scope2.ModuleA.AB

Dime.inject -> dime.ModuleXX.AA

Dime.inject -> not found - Dime can't drill to scopes

Dime.inject -> dime.ModuleC.CC

scope21.inject -> scope2.ModuleA.AA

scope21.inject -> scope21.ModuleC.CC

scope22.inject -> scope22.ModuleA.AC

scope22.inject -> scope2.ModuleC.CB

scope21.inject -> dime.ModuleX.BB

Features and bugs

Please file feature requests and bugs at the issue tracker.

Libraries

dime
Support for doing something awesome. [...]