Documentation
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Overview ¶
Package tasks provides functionality for services to run a fixed number of workers to conduct generic asynchronous tasks. This is an intentionally simple package to make sure that routine, non-critical work happens in a non-blocking fashion.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var (
ErrTaskManagerStopped = errors.New("the task manager is not running")
)
Functions ¶
func TaskScheduler ¶ added in v0.5.1
func TaskScheduler(wg *sync.WaitGroup, queue <-chan *TaskHandler, tasks chan<- *TaskHandler, stop <-chan struct{}, interval time.Duration)
TaskScheduler runs as a separate Go routine, listening for tasks on the retry channel and queueing them for a worker when their backoff period has expired.
func TaskWorker ¶
func TaskWorker(wg *sync.WaitGroup, tasks <-chan *TaskHandler)
Types ¶
type Option ¶ added in v0.5.1
type Option func(*options)
Option allows retries and backoff to be configured for individual tasks.
func WithBackoff ¶ added in v0.5.1
func WithBackoff(backoff backoff.BackOff) Option
Backoff strategy to use when retrying, default is an exponential backoff
func WithError ¶ added in v0.5.1
Log a specific error if all retries failed under the provided context. This error will be bundled with the errors that caused the retry failure and reported in a single error log message.
func WithRetries ¶ added in v0.5.1
Number of retries to attempt before giving up, default 0
type Task ¶
Workers in the task manager handle Tasks which can hold state and other information needed by the task. You can also specify a simple function to execute by using the TaskFunc to create a Task to provide to the task manager.
type TaskHandler ¶
type TaskHandler struct {
// contains filtered or unexported fields
}
func (*TaskHandler) Exec ¶ added in v0.5.1
func (h *TaskHandler) Exec()
Execute the wrapped task with the context. If the task fails, schedule the task to be retried using the backoff specified in the options.
type TaskManager ¶
TaskManagers execute Tasks using a fixed number of workers that operate in their own go routines. The TaskManager also has a fixed task queue size, so that if there are more tasks added to the task manager than the queue size, back pressure is applied.
func New ¶
func New(workers, queueSize int, retryInterval time.Duration) *TaskManager
New returns TaskManager, running the specified number of workers in their own Go routines and creating a queue of the specified size. The task manager is now ready to perform routine tasks!
func (*TaskManager) IsStopped ¶
func (tm *TaskManager) IsStopped() bool
Check if the task manager has been stopped (blocks until fully stopped).
func (*TaskManager) Queue ¶
func (tm *TaskManager) Queue(task Task, opts ...Option) error
Queue a task with a background context. Blocks if the queue is full.
func (*TaskManager) QueueContext ¶
Queue a task with the specified context. Blocks if the queue is full.
func (*TaskManager) Stop ¶
func (tm *TaskManager) Stop()
Stop the task manager waiting for all workers to stop their tasks before returning.
Source Files