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ModuleController ​

class ModuleController

Manages the full lifecycle of a single Module: dependency resolution, initialization, hot reload, and disposal.

The controller orchestrates the following sequence during initialize:

  1. Resolves and initializes all imported modules via GraphResolver.
  2. Validates Module.expects against available scopes.
  3. Calls Module.binds (private scope) and Module.exports (public scope).
  4. Applies any overrides to the binder.
  5. Calls Module.onInit for async setup.
dart
final controller = ModuleController(AppModule());
await controller.initialize({});

// Access dependencies:
final service = controller.binder.get<MyService>();

// Dispose when done:
await controller.dispose();

See also:

Constructors ​

ModuleController() ​

ModuleController(dynamic module, {dynamic binder, dynamic binderFactory, (void Function(dynamic))? overrides, ModuleOverrideScope? overrideScopeTree, List<dynamic> interceptors = const []})

Creates a controller for module with optional DI configuration.

When neither binder nor binderFactory is supplied, a default SimpleBinderFactory is used.

Implementation
dart
ModuleController(
  this.module, {
  Binder? binder,
  BinderFactory? binderFactory,
  this.overrides,
  ModuleOverrideScope? overrideScopeTree,
  this.interceptors = const [],
}) : _statusController = StreamController<ModuleStatus>.broadcast(),
     binder = binder ?? (binderFactory ?? SimpleBinderFactory()).create(),
     _binderFactory = binderFactory ?? SimpleBinderFactory(),
     overrideScope =
         overrideScopeTree?.withAdditionalOverride(overrides) ??
         (overrides != null
             ? ModuleOverrideScope(selfOverrides: overrides)
             : overrideScopeTree) {
  _statusController.add(ModuleStatus.initial);
}

Properties ​

binder final ​

final dynamic binder

The Binder that holds all dependency registrations for module.

Implementation
dart
final Binder binder;

currentStatus no setter ​

dynamic get currentStatus

Return the most recent ModuleStatus of this controller.

Implementation
dart
ModuleStatus get currentStatus => _currentStatus;

hashCode no setter inherited ​

int get hashCode

The hash code for this object.

A hash code is a single integer which represents the state of the object that affects operator == comparisons.

All objects have hash codes. The default hash code implemented by Object represents only the identity of the object, the same way as the default operator == implementation only considers objects equal if they are identical (see identityHashCode).

If operator == is overridden to use the object state instead, the hash code must also be changed to represent that state, otherwise the object cannot be used in hash based data structures like the default Set and Map implementations.

Hash codes must be the same for objects that are equal to each other according to operator ==. The hash code of an object should only change if the object changes in a way that affects equality. There are no further requirements for the hash codes. They need not be consistent between executions of the same program and there are no distribution guarantees.

Objects that are not equal are allowed to have the same hash code. It is even technically allowed that all instances have the same hash code, but if clashes happen too often, it may reduce the efficiency of hash-based data structures like HashSet or HashMap.

If a subclass overrides hashCode, it should override the operator == operator as well to maintain consistency.

Inherited from Object.

Implementation
dart
external int get hashCode;

importedControllers no setter ​

List<ModuleController> get importedControllers

References to the controllers of imported modules.

Implementation
dart
List<ModuleController> get importedControllers =>
    List.unmodifiable(_importedControllers);

interceptors final ​

final List<dynamic> interceptors

Ordered list of ModuleInterceptors notified at each lifecycle event.

Implementation
dart
final List<ModuleInterceptor> interceptors;

lastError no setter ​

Object? get lastError

Return the error captured during the last failed initialize call, or null if no error occurred.

Implementation
dart
Object? get lastError => _lastError;

module final ​

final dynamic module

The Module whose lifecycle this controller manages.

Implementation
dart
final Module module;

overrides final ​

final (void Function(dynamic))? overrides

Optional callback applied to the Binder after binds/exports to override registrations (e.g. for testing or feature flags).

Implementation
dart
final void Function(Binder)? overrides;

overrideScope final ​

final ModuleOverrideScope? overrideScope

Hierarchical override scope propagated to imported modules.

Implementation
dart
final ModuleOverrideScope? overrideScope;

runtimeType no setter inherited ​

Type get runtimeType

A representation of the runtime type of the object.

Inherited from Object.

Implementation
dart
external Type get runtimeType;

status no setter ​

Stream<dynamic> get status

Broadcast stream of ModuleStatus transitions.

Implementation
dart
Stream<ModuleStatus> get status => _statusController.stream;

Methods ​

configure() ​

void configure(dynamic args)

Passes args to the module's Configurable.configure method.

Throws ModuleLifecycleException if the module implements Configurable but the argument type does not match.

Implementation
dart
void configure(dynamic args) {
  if (module is Configurable) {
    try {
      (module as Configurable).configure(args);
    } catch (e) {
      &#47;&#47; Handle generic type mismatch gracefully or rethrow
      &#47;&#47; If we pass wrong type to configure(T args), Dart throws TypeError.
      throw ModuleLifecycleException(
        'Module ${module.runtimeType} failed to configure: '
        'Expected arguments of correct type for Configurable<T>.\n'
        'Error: $e',
        moduleType: module.runtimeType,
      );
    }
  }
}

dispose() ​

Future<void> dispose()

Disposes the module, its Binder, and closes the status stream.

Calls Module.onDispose, then DisposableBinder.dispose if the binder supports it, and finally closes the status stream.

Implementation
dart
Future<void> dispose() async {
  _updateStatus(ModuleStatus.disposed);

  &#47;&#47; Interceptor: onDispose (before closing stream so listeners can still react)
  for (var i in interceptors) {
    i.onDispose(module);
  }

  module.onDispose();
  if (binder is DisposableBinder) {
    await (binder as DisposableBinder).dispose();
  }
  _importedControllers.clear();
  await _statusController.close();
}

hotReload() ​

void hotReload()

Re-runs Module.binds and Module.exports under RegistrationStrategy.preserveExisting to refresh factory closures without losing singleton state.

No-op if the module is not in the ModuleStatus.loaded state.

Implementation
dart
void hotReload() {
  if (_currentStatus != ModuleStatus.loaded) return;

  &#47;&#47; Re-run binds to update factories.
  &#47;&#47; For MVP we simply call the hook and overwrite registrations.
  &#47;&#47; In the future SimpleBinder should support "updateFactoryOnly".

  void rebind() {
    final exportable = binder is ExportableBinder
        ? binder as ExportableBinder
        : null;
    exportable?.resetPublicScope();
    exportable?.disableExportMode();
    module.binds(binder);
    _applyOverridesIfNeeded();
    exportable?.enableExportMode();
    module.exports(binder);
    exportable?.disableExportMode();
    exportable?.sealPublicScope();
  }

  final aware = _registrationAwareBinder;
  if (aware != null) {
    aware.runWithStrategy(RegistrationStrategy.preserveExisting, () {
      rebind();
    });
  } else {
    rebind();
  }

  &#47;&#47; User hook
  module.hotReload(binder);
}

initialize() ​

Future<void> initialize(Map<ModuleRegistryKey, ModuleController> globalModuleRegistry, {Set<Type>? resolutionStack})

Runs the full initialization lifecycle for this module.

Uses globalModuleRegistry to deduplicate module controllers across concurrent import branches. Pass resolutionStack for cycle detection.

Throws CircularDependencyException, ModuleConfigurationException, or ModuleLifecycleException on failure.

Implementation
dart
Future<void> initialize(
  Map<ModuleRegistryKey, ModuleController> globalModuleRegistry, {
  Set<Type>? resolutionStack,
}) async {
  if (_currentStatus == ModuleStatus.loading ||
      _currentStatus == ModuleStatus.loaded) {
    return;
  }

  &#47;&#47; Interceptor: onInit
  for (var i in interceptors) {
    i.onInit(module);
  }

  _updateStatus(ModuleStatus.loading);

  try {
    &#47;&#47; 1. Resolve Imports via GraphResolver
    final resolver = GraphResolver();
    final imports = await resolver.resolveAndInitImports(
      module,
      globalModuleRegistry,
      _binderFactory,
      resolutionStack: resolutionStack,
      interceptors: interceptors,
      overrideScope: overrideScope,
    );

    _importedControllers.addAll(imports);
    final importBinders = imports.map((c) => c.binder).toList();

    &#47;&#47; 2. Configure Binder with imports
    binder.addImports(importBinders);

    &#47;&#47; 3. Validate Expects (Fail-Fast)
    for (final expectedType in module.expects) {
      &#47;&#47; contains checks the entire chain (Local + Imports + Parent).
      &#47;&#47; At this stage Local is empty (binds hasn't been called yet),
      &#47;&#47; so we're effectively checking Imports and Parent.
      if (!binder.contains(expectedType)) {
        throw ModuleConfigurationException(
          "Module ${module.runtimeType} expects dependency of type '$expectedType', "
          'but it was not found in Parent Scope or Imports.\n'
          "Check if the parent module exports it or if it's correctly imported.",
          moduleType: module.runtimeType,
        );
      }
    }

    &#47;&#47; 4. Binds (Private & Public)
    final exportable = binder is ExportableBinder
        ? binder as ExportableBinder
        : null;
    exportable?.disableExportMode();
    module.binds(binder);

    _applyOverridesIfNeeded();

    exportable?.enableExportMode();
    module.exports(binder);
    exportable?.disableExportMode();
    exportable?.sealPublicScope();

    &#47;&#47; 5. Async Init
    await module.onInit();

    _updateStatus(ModuleStatus.loaded);

    &#47;&#47; Interceptor: onLoaded
    for (var i in interceptors) {
      i.onLoaded(module);
    }
  } catch (e) {
    _lastError = e;
    _updateStatus(ModuleStatus.error);

    &#47;&#47; Interceptor: onError
    for (var i in interceptors) {
      i.onError(module, e);
    }

    rethrow;
  }
}

noSuchMethod() inherited ​

dynamic noSuchMethod(Invocation invocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dart
dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

dart
class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Object.

Implementation
dart
@pragma("vm:entry-point")
@pragma("wasm:entry-point")
external dynamic noSuchMethod(Invocation invocation);

toString() inherited ​

String toString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Inherited from Object.

Implementation
dart
external String toString();

Operators ​

operator ==() inherited ​

bool operator ==(Object other)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

  • Total: It must return a boolean for all arguments. It should never throw.

  • Reflexive: For all objects o, o == o must be true.

  • Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

  • Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Inherited from Object.

Implementation
dart
external bool operator ==(Object other);