github.com/cloudbase/juju-core@v0.0.0-20140504232958-a7271ac7912f/worker/upgrader/error.go (about)

     1  // Copyright 2014 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package upgrader
     5  
     6  import (
     7  	agenttools "launchpad.net/juju-core/agent/tools"
     8  	"launchpad.net/juju-core/version"
     9  )
    10  
    11  // UpgradeReadyError is returned by an Upgrader to report that
    12  // an upgrade is ready to be performed and a restart is due.
    13  type UpgradeReadyError struct {
    14  	AgentName string
    15  	OldTools  version.Binary
    16  	NewTools  version.Binary
    17  	DataDir   string
    18  }
    19  
    20  func (e *UpgradeReadyError) Error() string {
    21  	return "must restart: an agent upgrade is available"
    22  }
    23  
    24  // ChangeAgentTools does the actual agent upgrade.
    25  // It should be called just before an agent exits, so that
    26  // it will restart running the new tools.
    27  func (e *UpgradeReadyError) ChangeAgentTools() error {
    28  	tools, err := agenttools.ChangeAgentTools(e.DataDir, e.AgentName, e.NewTools)
    29  	if err != nil {
    30  		return err
    31  	}
    32  	logger.Infof("upgraded from %v to %v (%q)", e.OldTools, tools.Version, tools.URL)
    33  	return nil
    34  }