taskrunner

Documentation

Overview

Supports starting many cancellable goroutines whose exit and their error codes we can wait on.

Works similar to golang.org/x/sync/errgroup but provides richer logging (tasks are named) and errors

• The tasks are expected to run forever, until context cancellation (e.g. task stopping before cancellation even with nil error is considered an error).
• If any of the tasks fail, sibling tasks are canceled as well.

Index

• type Runner
  • func New(ctx context.Context, logger *log.Logger) *Runner
  • func (t *Runner) Done() <-chan error
  • func (t *Runner) Start(taskName string, fn func(ctx context.Context) error)
  • func (t *Runner) Wait() error

Types

type Runner

type Runner struct {
	// contains filtered or unexported fields
}

func New

func New(ctx context.Context, logger *log.Logger) *Runner

func (*Runner) Done

func (t *Runner) Done() <-chan error

same semantics as Wait(), but returns chan so you can do other stuff while waiting.

NOTE: same note as for Wait()

func (*Runner) Start

func (t *Runner) Start(taskName string, fn func(ctx context.Context) error)

not safe to be called after you call Wait() or Done() not safe for concurrent use

func (*Runner) Wait

func (t *Runner) Wait() error

Returns: - nil if all task exits were expected and errors were nil - err if any of the tasks exited unexpectedly or exit was expected but errored

NOTE: don't have multiple goroutines concurrently use Done() or Wait(). i.e. you can

call Done() and even after that call Wait(), but don't do it concurrently (the
channel only sends one value)