github.com/niedbalski/juju@v0.0.0-20190215020005-8ff100488e47/apiserver/common/machinestatus.go (about)

     1  // Copyright 2016 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package common
     5  
     6  import (
     7  	"github.com/juju/juju/core/status"
     8  	"github.com/juju/juju/state"
     9  )
    10  
    11  // MachineStatusGetter defines the machine functionality
    12  // required to status.
    13  type MachineStatusGetter interface {
    14  	Status() (status.StatusInfo, error)
    15  	AgentPresence() (bool, error)
    16  	Id() string
    17  	Life() state.Life
    18  }
    19  
    20  // MachineStatus returns the machine agent status for a given
    21  // machine, with special handling for agent presence.
    22  func (c *ModelPresenceContext) MachineStatus(machine MachineStatusGetter) (status.StatusInfo, error) {
    23  	machineStatus, err := machine.Status()
    24  	if err != nil {
    25  		return status.StatusInfo{}, err
    26  	}
    27  
    28  	if !canMachineBeDown(machineStatus) {
    29  		// The machine still being provisioned - there's no point in
    30  		// enquiring about the agent liveness.
    31  		return machineStatus, nil
    32  	}
    33  
    34  	agentAlive, err := c.machinePresence(machine)
    35  	if err != nil {
    36  		// We don't want any presence errors affecting status.
    37  		logger.Debugf("error determining presence for machine %s: %v", machine.Id(), err)
    38  		return machineStatus, nil
    39  	}
    40  	if machine.Life() != state.Dead && !agentAlive {
    41  		machineStatus.Status = status.Down
    42  		machineStatus.Message = "agent is not communicating with the server"
    43  	}
    44  	return machineStatus, nil
    45  }
    46  
    47  func canMachineBeDown(machineStatus status.StatusInfo) bool {
    48  	switch machineStatus.Status {
    49  	case status.Pending, status.Stopped:
    50  		return false
    51  	}
    52  	return true
    53  }