Golang X.Verbose方法代碼示例

// AtomicAction performs an action 'atomically' by keeping track of successfully
// completed actions in the supplied completion log and re-running them if they
// are not successfully logged therein after deleting the entire contents of the
// dir parameter. Consequently it does not make sense to apply AtomicAction to
// the same directory in sequence.
func AtomicAction(jirix *jiri.X, installFn func() error, dir, message string) error {
	atomicFn := func() error {
		completionLogPath := filepath.Join(dir, ".complete")
		s := jirix.NewSeq()
		if dir != "" {
			if exists, _ := s.IsDir(dir); exists {
				// If the dir exists but the completionLogPath doesn't, then it
				// means the previous action didn't finish.
				// Remove the dir so we can perform the action again.
				if exists, _ := s.IsFile(completionLogPath); !exists {
					s.RemoveAll(dir).Done()
				} else {
					if jirix.Verbose() {
						fmt.Fprintf(jirix.Stdout(), "AtomicAction: %s already completed in %s\n", message, dir)
					}
					return nil
				}
			}
		}
		if err := installFn(); err != nil {
			if dir != "" {
				s.RemoveAll(dir).Done()
			}
			return err
		}
		return s.WriteFile(completionLogPath, []byte("completed"), DefaultFilePerm).Done()
	}
	return jirix.NewSeq().Call(atomicFn, message).Done()
}

// ensureAction ensures that the requested profile and target
// is installed/uninstalled, installing/uninstalling it if and only if necessary.
func ensureAction(jirix *jiri.X, pdb *profiles.DB, action profiles.Action, installer, profile string, root jiri.RelPath, target profiles.Target) error {
	verb := ""
	switch action {
	case profiles.Install:
		verb = "install"
	case profiles.Uninstall:
		verb = "uninstall"
	default:
		return fmt.Errorf("unrecognised action %v", action)
	}
	if jirix.Verbose() {
		fmt.Fprintf(jirix.Stdout(), "%s %v %s\n", verb, action, target)
	}
	if t := pdb.LookupProfileTarget(installer, profile, target); t != nil {
		if jirix.Verbose() {
			fmt.Fprintf(jirix.Stdout(), "%v %v is already %sed as %v\n", profile, target, verb, t)
		}
		return nil
	}
	mgr := LookupManager(profiles.QualifiedProfileName(installer, profile))
	if mgr == nil {
		return fmt.Errorf("profile %v is not supported", profile)
	}
	version, err := mgr.VersionInfo().Select(target.Version())
	if err != nil {
		return err
	}
	target.SetVersion(version)
	if jirix.Verbose() {
		fmt.Fprintf(jirix.Stdout(), "%s %s %s\n", verb, profile, target.DebugString())
	}
	if action == profiles.Install {
		return mgr.Install(jirix, pdb, root, target)
	}
	return mgr.Uninstall(jirix, pdb, root, target)
}