// NewUndertaker returns a worker which processes a dying environment.
func NewUndertaker(client apiundertaker.UndertakerClient, clock uc.Clock) worker.Worker {
f := func(stopCh <-chan struct{}) error {
result, err := client.EnvironInfo()
if err != nil {
return errors.Trace(err)
}
if result.Error != nil {
return errors.Trace(result.Error)
}
envInfo := result.Result
if envInfo.Life == params.Alive {
return errors.Errorf("undertaker worker should not be started for an alive environment: %q", envInfo.GlobalName)
}
if envInfo.Life == params.Dying {
// Process the dying environment. This blocks until the environment
// is dead.
processDyingEnv(client, clock, stopCh)
}
// If environ is not alive or dying, it must be dead.
if envInfo.IsSystem {
// Nothing to do. We don't remove environment docs for a state server
// environment.
return nil
}
cfg, err := client.EnvironConfig()
if err != nil {
return errors.Trace(err)
}
env, err := environs.New(cfg)
if err != nil {
return errors.Trace(err)
}
err = env.Destroy()
if err != nil {
return errors.Trace(err)
}
tod := clock.Now()
if envInfo.TimeOfDeath != nil {
// If TimeOfDeath is not nil, the environment was already dead
// before the worker was started. So we use the recorded time of
// death. This may happen if the system is rebooted after an
// environment is set to dead, but before the environ docs are
// removed.
tod = *envInfo.TimeOfDeath
}
// Process the dead environment
return processDeadEnv(client, clock, tod, stopCh)
}
return worker.NewSimpleWorker(f)
}
