func (pc *PasswordChanger) setMongoPassword(entity state.Entity, password string) error {
type mongoPassworder interface {
SetMongoPassword(password string) error
}
// We set the mongo password first on the grounds that
// if it fails, the agent in question should still be able
// to authenticate to another API server and ask it to change
// its password.
if entity0, ok := entity.(mongoPassworder); ok {
if err := entity0.SetMongoPassword(password); err != nil {
return err
}
logger.Infof("setting mongo password for %q", entity.Tag())
return nil
}
return NotSupportedError(entity.Tag(), "mongo access")
}
func startPingerIfAgent(clock clock.Clock, root *apiHandler, entity state.Entity) error {
// worker runs presence.Pingers -- absence of which will cause
// embarrassing "agent is lost" messages to show up in status --
// until it's stopped. It's stored in resources purely for the
// side effects: we don't record its id, and nobody else
// retrieves it -- we just expect it to be stopped when the
// connection is shut down.
agent, ok := entity.(statepresence.Agent)
if !ok {
return nil
}
worker, err := presence.New(presence.Config{
Identity: entity.Tag(),
Start: presenceShim{agent}.Start,
Clock: clock,
RetryDelay: 3 * time.Second,
})
if err != nil {
return err
}
root.getResources().Register(worker)
// pingTimeout, by contrast, *is* used by the Pinger facade to
// stave off the call to action() that will shut down the agent
// connection if it gets lackadaisical about sending keepalive
// Pings.
//
// Do not confuse those (apiserver) Pings with those made by
// presence.Pinger (which *do* happen as a result of the former,
// but only as a relatively distant consequence).
//
// We should have picked better names...
action := func() {
logger.Debugf("closing connection due to ping timout")
if err := root.getRpcConn().Close(); err != nil {
logger.Errorf("error closing the RPC connection: %v", err)
}
}
pingTimeout := newPingTimeout(action, clock, maxClientPingInterval)
return root.getResources().RegisterNamed("pingTimeout", pingTimeout)
}