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Conductor does the least amount possible to solve the problem of starting up dependant services and shutting them down gracefully.

A service implements the conductor.Service interface via a Run method which takes 3 channels:

• started chan bool - Send true when your service is running
• stopped chan bool - Send true when your service has stopped
• stop chan context.Context - Select on this to be notified of shutdown, context with timeout.

type MyService struct {}

func (t MyService) Run(started, stopped chan bool, stop chan context.Context) error {
    go func() {
      // Do some startup stuff then signal we're running
      started <- true
      select {
        case ctx := <- stop:
          // do some shutdown stuff then signal we're done
          stopped <- true
      }
    }()
    return nil
}

c := conductor.New()
c.Service("Service 1", MyService{})
c.Service("Service 2", MyService{})
<- c.Start() // wait for graceful shutdown

You can call Conductor.Stop() which will close the Shutdown channel returned by Conductor.Start() once all services have closed or timeout is reached.

Everyone loves options, these functions can all have their return values passed to Conductor.Run to modify the behaviour of the Conductor.

• HookSignals() Will tell the conductor to listen for kill/stop signals and shutdown services.
• StartupTimeout(time.Duration) How long to wait for a service to start (Default 5s).
• ShutdownTimeout(time.Duration) How long to wait for a service to stop gracefully (Default 5s).
• Noisy() Log services starting and stopping via standard log.

c := conductor.New(
    conductor.HookSignals(),
    conductor.Noisy(),
    conductor.ShutdownTimeout(time.Duration(20 * time.Second)))