// openAPIState opens the API using the given information, and
// returns the opened state and the api entity with
// the given tag. The given changeConfig function is
// called if the password changes to set the password.
func openAPIState(
agentConfig agent.Config,
a Agent,
) (_ *api.State, _ *apiagent.Entity, err error) {
// We let the API dial fail immediately because the
// runner's loop outside the caller of openAPIState will
// keep on retrying. If we block for ages here,
// then the worker that's calling this cannot
// be interrupted.
info := agentConfig.APIInfo()
st, err := apiOpen(info, api.DialOpts{})
usedOldPassword := false
if params.IsCodeUnauthorized(err) {
// We've perhaps used the wrong password, so
// try again with the fallback password.
info := *info
info.Password = agentConfig.OldPassword()
usedOldPassword = true
st, err = apiOpen(&info, api.DialOpts{})
}
if err != nil {
if params.IsCodeNotProvisioned(err) {
return nil, nil, worker.ErrTerminateAgent
}
if params.IsCodeUnauthorized(err) {
return nil, nil, worker.ErrTerminateAgent
}
return nil, nil, err
}
defer func() {
if err != nil {
st.Close()
}
}()
entity, err := st.Agent().Entity(a.Tag())
if err == nil && entity.Life() == params.Dead {
return nil, nil, worker.ErrTerminateAgent
}
if err != nil {
if params.IsCodeUnauthorized(err) {
return nil, nil, worker.ErrTerminateAgent
}
return nil, nil, err
}
if usedOldPassword {
// We succeeded in connecting with the fallback
// password, so we need to create a new password
// for the future.
newPassword, err := utils.RandomPassword()
if err != nil {
return nil, nil, err
}
// Change the configuration *before* setting the entity
// password, so that we avoid the possibility that
// we might successfully change the entity's
// password but fail to write the configuration,
// thus locking us out completely.
if err := a.ChangeConfig(func(c agent.ConfigSetter) {
c.SetPassword(newPassword)
c.SetOldPassword(info.Password)
}); err != nil {
return nil, nil, err
}
if err := entity.SetPassword(newPassword); err != nil {
return nil, nil, err
}
}
return st, entity, nil
}