Runner helps you to not reinvent the wheel on certain type of applications. Often you begin your application by starting multiple goroutines to do separate work. Imagine a server accepting http, tcp, and other protocols. You probably also create WaitGroups and/or channels to sync these goroutines. Runner does all that for you.

API

The API is promised to never break existing projects using this library. Documentation available on GoDoc.

Examples

Minimalistic

var r runner.Runner

r.Run(runHTTP)
r.Run(runTCP)

r.Wait()

runHTTP and runTCP are both of type func(). r.Run will run both functions in separate goroutines, and r.Wait() waits until both functions exit.

Exit notification

When runTCP exits, it might be because the application is supposed to exit alltogether, or there was an irrecoverable error. In that case, you might want HTTP to exit aswell. Run* methods return a channel which is closed when its running function returns.

ctx, cancel := context.WithCancel(context.Background())
r := runner.Runner{Ctx: ctx}

select {
case <-r.RunContext(runHTTP):
case <-r.RunContext(runTCP):
}

cancel()
r.Wait()

Both runHTTP and runTCP are now of type func(context.Context) and are given the context Runner.Ctx. If either runHTTP or runTCP returns, select will break, the context will be cancelled, making the other function exit aswell in due time, and r.Wait() waits for that.

Signals

Runner contains a convenience method to work with OS signals

ctx, cancel := context.WithCancel(context.Background())
r := runner.Runner{Ctx: ctx}

select {
case <-r.RunContext(runHTTP):
case <-r.RunContext(runTCP):
case <-r.RunSigs(syscall.SIGINT, syscall.SIGTERM):
}

cancel()
r.Wait()

If either runHTTP or runTCP returns, or SIGINT/SIGTERM is received, the context will be cancelled and we wait for everything to clean up.

Multiple parameters

You might want to pass more than just a context to your function. To archive this, you may use closures

ctx, cancel := context.WithCancel(context.Background())
r := runner.Runner{Ctx: ctx}

select {
case <-r.Run(func() { runSomething(ctx, 1, 2, 3) }):
case <-r.RunSigs(syscall.SIGINT, syscall.SIGTERM):
}

cancel()
r.Wait()

License

MIT