LevitTaskEngine class

A standalone engine for named, cancellable asynchronous work.

The engine provides global priority/concurrency scheduling while conflict policies define ordering for submissions that share a logical task ID.

Implemented types

Constructors

LevitTaskEngine({required int maxConcurrent, LevitTaskCacheProvider? cacheProvider, void onTaskError(Object error, StackTrace stackTrace)?, void onTaskEvent(LevitTaskEvent event)?, String ownerPath = '?'})
Creates a task engine with maxConcurrent workers.

Properties

cacheProvider ↔ LevitTaskCacheProvider
The cache provider used by this engine.
getter/setter pair
hashCode → int
The hash code for this object.
no setterinherited
maxConcurrent ↔ int
The maximum number of concurrent admitted executions.
getter/setter pair
onTaskError ↔ void Function(Object error, StackTrace stackTrace)?
Optional global error handler for terminal task failures.
getter/setter pair
onTaskEvent ↔ void Function(LevitTaskEvent event)?
Optional local lifecycle instrumentation callback.
getter/setter pair
ownerPath ↔ String
Diagnostic path attached to task events.
getter/setter pair
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

cancel(String id) → void
Cooperatively cancels all outstanding executions for logical id.
cancelAll() → void
Cooperatively cancels every outstanding execution.
cancelExecution(String executionId) → bool
Cooperatively cancels one admitted execution.
config({int? maxConcurrent, LevitTaskCacheProvider? cacheProvider, String? ownerPath, void onTaskError(Object error, StackTrace stackTrace)? = _onTaskErrorUnset, void onTaskEvent(LevitTaskEvent event)? = _onTaskEventUnset}) → void
Dynamically updates engine configuration.
dispose() → void
Releases resources held by this object.
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
schedule<T>(FutureOr<T> task(LevitTaskContext context), {String? id, TaskPriority priority = TaskPriority.normal, TaskConflictPolicy conflictPolicy = TaskConflictPolicy.reject, int retries = 0, Duration? retryDelay, bool useExponentialBackoff = true, void onError(Object error, StackTrace stackTrace)?, TaskCachePolicy<T>? cachePolicy, void onStart()?, void onSuccess(T result)?, void onProgress(double progress)?, void onCancel()?, void onEvent(LevitTaskEvent event)?, LevitTaskMetadata? metadata, String? debugName}) → Future<T?>
Schedules task and returns only its eventual result.
scheduleIsolate<I, T>(LevitIsolateTask<I, T> task, I input, {String? id, TaskPriority priority = TaskPriority.normal, TaskConflictPolicy conflictPolicy = TaskConflictPolicy.reject, int retries = 0, Duration? retryDelay, bool useExponentialBackoff = true, void onError(Object error, StackTrace stackTrace)?, TaskCachePolicy<T>? cachePolicy, void onStart()?, void onSuccess(T result)?, void onProgress(double progress)?, void onCancel()?, void onEvent(LevitTaskEvent event)?, LevitTaskMetadata? metadata, String? debugName}) → Future<T?>
Schedules a message-safe top-level/static task in a new isolate.
submit<T>(FutureOr<T> task(LevitTaskContext context), {String? id, TaskPriority priority = TaskPriority.normal, TaskConflictPolicy conflictPolicy = TaskConflictPolicy.reject, int retries = 0, Duration? retryDelay, bool useExponentialBackoff = true, void onError(Object error, StackTrace stackTrace)?, TaskCachePolicy<T>? cachePolicy, void onStart()?, void onSuccess(T result)?, void onProgress(double progress)?, void onCancel()?, void onEvent(LevitTaskEvent event)?, LevitTaskMetadata? metadata, String? debugName}) → LevitTaskExecution<T>
Submits task and returns its execution identity and result.
submitIsolate<I, T>(LevitIsolateTask<I, T> task, I input, {String? id, TaskPriority priority = TaskPriority.normal, TaskConflictPolicy conflictPolicy = TaskConflictPolicy.reject, int retries = 0, Duration? retryDelay, bool useExponentialBackoff = true, void onError(Object error, StackTrace stackTrace)?, TaskCachePolicy<T>? cachePolicy, void onStart()?, void onSuccess(T result)?, void onProgress(double progress)?, void onCancel()?, void onEvent(LevitTaskEvent event)?, LevitTaskMetadata? metadata, String? debugName}) → LevitTaskExecution<T>
Submits a message-safe top-level/static task in a new isolate.
toString() → String
A string representation of this object.
inherited
updateProgress(String id, double progress) → void
Reports progress for the latest running execution of logical id.

Operators

operator ==(Object other) → bool
The equality operator.
inherited