// getAllUnits returns a list of all principal and subordinate units
// assigned to the given machine.
func getAllUnits(st *state.State, machineTag string) ([]string, error) {
machine, err := st.Machine(state.MachineIdFromTag(machineTag))
if err != nil {
return nil, err
}
// Start a watcher on machine's units, read the initial event and stop it.
watch := machine.WatchUnits()
defer watch.Stop()
if units, ok := <-watch.Changes(); ok {
return units, nil
}
return nil, fmt.Errorf("cannot obtain units of machine %q: %v", machineTag, watch.Err())
}
func (a *MachineAgent) Entity(st *state.State) (AgentState, error) {
m, err := st.Machine(a.MachineId)
if err != nil {
return nil, err
}
// Check the machine nonce as provisioned matches the agent.Conf value.
if !m.CheckProvisioned(a.Conf.MachineNonce) {
// The agent is running on a different machine to the one it
// should be according to state. It must stop immediately.
log.Errorf("running machine %v agent on inappropriate instance", m)
return nil, worker.ErrTerminateAgent
}
return m, nil
}
func (a *MachineAgent) Entity(st *state.State) (AgentState, error) {
return st.Machine(a.MachineId)
}