WaitFor Test

log.txt

=== RUN   TestServersCreateDestroy
2016/10/22 16:53:53 Checkpoint 2
2016/10/22 16:53:55 Checkpoint 2
2016/10/22 16:53:57 Checkpoint 2
2016/10/22 16:53:59 Checkpoint 2
2016/10/22 16:54:00 Checkpoint 2
2016/10/22 16:54:02 Checkpoint 2
2016/10/22 16:54:03 Checkpoint 2
2016/10/22 16:54:05 Checkpoint 2
2016/10/22 16:54:07 Checkpoint 2
--- PASS: TestServersCreateDestroy (19.53s)

wait_for.go

func WaitFor(timeout int, predicate func() (bool, error)) error {
  // Check condition before first wait
  satisfied, err := predicate()
  if err != nil {
    return err
  }
  if satisfied {
    return nil
  }

  for {
    select {
    case <-time.After(time.Duration(timeout) * time.Second):
      // Check if condition was satisfied between
      // timeout and the last check
      log.Printf("Checkpoint 1")
      satisfied, err := predicate()
      if err != nil {
        return err
      }
      if satisfied {
        return nil
      }
      return errors.New("A timeout occurred")
    case <-time.After(time.Second):
      // Execute the function
      log.Printf("Checkpoint 2")
      satisfied, err := predicate()
      if err != nil {
        return err
      }
      if satisfied {
        return nil
      }
    }
  }
}

func WaitForComputeStatus(client *gophercloud.ServiceClient, server *servers.Server, status string) error {                                                                                            
  return gophercloud.WaitFor(2, func() (bool, error) {                                             
    latest, err := servers.Get(client, server.ID).Extract()                                        
    if err != nil {                                                                                
      return false, err                                                                            
    }                                                                                              
                                                                                                   
    if latest.Status == status {                                                                   
      // Success!                                                                                  
      return true, nil                                                                             
    }                                                                                              
                                                                                                   
    if latest.Status == "ERROR" {                                                                  
      return false, fmt.Errorf("Instance in ERROR state")                                          
    }                                                                                              
                                                                                                   
    return false, nil                                                                              
  })                                                                                               
}