nest_frog library

Dart Frog integration for Nest Dart - bringing dependency injection and modular architecture to Dart Frog backend applications.

This library provides Dart Frog-specific middleware and utilities for the Nest Dart framework, and re-exports all core functionality from nest_core for convenience.

Classes

ApplicationContainer

Application container that manages modules and dependency injection Provides centralized service resolution with module-based encapsulation

Disposable

If objects that are registered inside GetIt implements Disposable the onDispose method will be called whenever that Object is unregistered, reset or its enclosing Scope is popped

GetIt

Very simple and easy to use service locator You register your object creation factory or an instance of an object with registerFactory, registerSingleton or registerLazySingleton And retrieve the desired object using get or call your locator as function as its a callable class Additionally GetIt offers asynchronous creation functions as well as functions to synchronize the async initialization of multiple Singletons

InitDependency

Data structure used to identify a dependency by type and instanceName

Locator

Interface for dependency injection container Provides type-safe access to services with export restrictions

Modular

Unified Modular class for Dart Frog integration Combines container management with context-based service access

ModularContext

Context wrapper that provides service access

Module

Abstract base class for all modules in the framework Provides modular dependency injection with controlled service access

ModuleContext

Context for tracking module dependencies and exports

ObjectRegistration<T extends Object>

ShadowChangeHandlers

If an object implements the ShadowChangeHandler if will get notified if an Object with the same registration type and name is registered on a higher scope which will shadow it. It also will get notified if the shadowing object is removed from GetIt

WillSignalReady

If your singleton that you register wants to use the manually signalling of its ready state, it can implement this interface class instead of using the signalsReady parameter of the registration functions (you don't really have to implement much ;-) )

Enums

ObjectRegistrationType

You will see a rather esoteric looking test (const Object() is! T) at several places. It tests if T is a real type and not Object or dynamic. For each registered factory/singleton an ObjectRegistration<T> is created it holds either the instance of a Singleton or/and the creation functions for creating an instance when get is called

Functions

nestFrogMiddleware(Module appModule) → Middleware

Create NestFrog middleware for Dart Frog This middleware initializes the container and provides dependency injection

throwIf(bool condition, Object error) → void

Two handy functions that help me to express my intention clearer and shorter to check for runtime errors

throwIfNot(bool condition, Object error) → void

Typedefs

DisposingFunc<T> = FutureOr Function(T param)

Signature for disposing function because closures like (x){} have a return type of Null we don't use FutureOr<void>

FactoryFunc<T> = T Function()

Signature of the factory function used by non async factories

FactoryFuncAsync<T> = Future<T> Function()

Signature of the factory function used by async factories

FactoryFuncParam<T, P1, P2> = T Function(P1 param1, P2 param2)

For Factories that expect up to two parameters if you need only one use void for the one you don't use

FactoryFuncParamAsync<T, P1, P2> = Future<T> Function(P1 param1, P2 param2)

For async Factories that expect up to two parameters if you need only one use void for the one you don't use

ScopeDisposeFunc = FutureOr Function()

Signature for disposing function on scope level

Exceptions / Errors

ServiceNotExportedException

Exception thrown when trying to access a non-exported service

WaitingTimeOutException