// WaitForEnviron waits for an valid environment to arrive from
// the given watcher. It terminates with tomb.ErrDying if
// it receives a value on dying.
func WaitForEnviron(w *state.EnvironConfigWatcher, dying <-chan struct{}) (environs.Environ, error) {
for {
select {
case <-dying:
return nil, tomb.ErrDying
case config, ok := <-w.Changes():
if !ok {
return nil, watcher.MustErr(w)
}
environ, err := environs.New(config)
if err == nil {
return environ, nil
}
log.Errorf("worker: loaded invalid environment configuration: %v", err)
loadedInvalid()
}
}
}
func stopWatcher(c *C, w *state.EnvironConfigWatcher) {
err := w.Stop()
c.Check(err, IsNil)
}