Documentation
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Overview ¶
Package agdservice defines types and interfaces for long-running services.
TODO(a.garipov): Move more to golibs.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type RefreshWorker ¶
type RefreshWorker struct {
// contains filtered or unexported fields
}
RefreshWorker is an [Interface] implementation that updates its Refresher every tick of the provided ticker.
func NewRefreshWorker ¶
func NewRefreshWorker(c *RefreshWorkerConfig) (w *RefreshWorker)
NewRefreshWorker returns a new valid *RefreshWorker with the provided parameters. c must not be nil.
func (*RefreshWorker) Shutdown ¶
func (w *RefreshWorker) Shutdown(ctx context.Context) (err error)
Shutdown implements the service.Interface interface for *RefreshWorker.
NOTE: The context provided by [RefreshWorkerConfig.Context] is not used for the shutdown refresh.
func (*RefreshWorker) Start ¶
func (w *RefreshWorker) Start(_ context.Context) (err error)
Start implements the service.Interface interface for *RefreshWorker. err is always nil.
type RefreshWorkerConfig ¶
type RefreshWorkerConfig struct {
// Context is used to provide a context for the Refresh method of Refresher.
//
// NOTE: It is not used for the shutdown refresh.
//
// TODO(a.garipov): Consider ways of fixing that.
Context func() (ctx context.Context, cancel context.CancelFunc)
// Refresher is the entity being refreshed.
Refresher Refresher
// Logger is used for logging the operation of the worker.
Logger *slog.Logger
// Interval is the refresh interval. Must be greater than zero.
//
// TODO(a.garipov): Consider switching to an interface à la
// github.com/robfig/cron/v3.Schedule.
Interval time.Duration
// RefreshOnShutdown, if true, instructs the worker to call the Refresher's
// Refresh method before shutting down the worker. This is useful for items
// that should persist to disk or remote storage before shutting down.
RefreshOnShutdown bool
// RandomizeStart, if true, instructs the worker to sleep before starting a
// refresh. The duration of the sleep is a random duration of up to 10 % of
// Interval.
//
// TODO(a.garipov): Switch to something like a cron schedule and see if this
// is still necessary
RandomizeStart bool
}
RefreshWorkerConfig is the configuration structure for a *RefreshWorker.
type Refresher ¶
type Refresher interface {
// Refresh is called by a [RefreshWorker]. The error returned by Refresh is
// only returned from [RefreshWorker.Shutdown] and only when
// [RefreshWorkerConfig.RefreshOnShutdown] is true. In all other cases, the
// error is ignored, and refreshers must handle error reporting themselves.
Refresh(ctx context.Context) (err error)
}
Refresher is the interface for entities that can update themselves.
type RefresherFunc ¶
RefresherFunc is an adapter to allow the use of ordinary functions as Refresher.
type RefresherWithErrColl ¶
type RefresherWithErrColl struct {
// contains filtered or unexported fields
}
RefresherWithErrColl reports all refresh errors to errColl and logs them using a provided logging function.
func NewRefresherWithErrColl ¶
func NewRefresherWithErrColl( refr Refresher, logger *slog.Logger, errColl errcoll.Interface, prefix string, ) (wrapped *RefresherWithErrColl)
NewRefresherWithErrColl wraps refr into a refresher that collects errors and logs them.
Source Files