func openState(agentConfig agent.Config) (_ *state.State, _ *state.Machine, err error) {
info, ok := agentConfig.StateInfo()
if !ok {
return nil, nil, fmt.Errorf("no state info available")
}
st, err := state.Open(info, state.DialOpts{}, environs.NewStatePolicy())
if err != nil {
return nil, nil, err
}
defer func() {
if err != nil {
st.Close()
}
}()
m0, err := st.FindEntity(agentConfig.Tag())
if err != nil {
if errors.IsNotFound(err) {
err = worker.ErrTerminateAgent
}
return nil, nil, err
}
m := m0.(*state.Machine)
if m.Life() == state.Dead {
return nil, nil, worker.ErrTerminateAgent
}
// Check the machine nonce as provisioned matches the agent.Conf value.
if !m.CheckProvisioned(agentConfig.Nonce()) {
// The agent is running on a different machine to the one it
// should be according to state. It must stop immediately.
logger.Errorf("running machine %v agent on inappropriate instance", m)
return nil, nil, worker.ErrTerminateAgent
}
return st, m, nil
}
func refreshConfig(c *gc.C, config agent.Config) agent.ConfigSetterWriter {
config1, err := agent.ReadConfig(agent.ConfigPath(config.DataDir(), config.Tag()))
c.Assert(err, gc.IsNil)
return config1
}
// NewWorker returns a worker that keeps track of
// the machine's authorised ssh keys and ensures the
// ~/.ssh/authorized_keys file is up to date.
func NewWorker(st *keyupdater.State, agentConfig agent.Config) worker.Worker {
kw := &keyupdaterWorker{st: st, tag: agentConfig.Tag()}
return worker.NewNotifyWorker(kw)
}
// NewMachiner returns a Worker that will wait for the identified machine
// to become Dying and make it Dead; or until the machine becomes Dead by
// other means.
func NewMachiner(st *machiner.State, agentConfig agent.Config) worker.Worker {
mr := &Machiner{st: st, tag: agentConfig.Tag()}
return worker.NewNotifyWorker(mr)
}
