handler

type AppEvT interface{} // Type of application events.

type CCResT interface{} // Return type of coordinator calls.

type CoordCall struct {
	Seqno  SeqnoT              `json:"seqno"`
	Op     string              `json:"op"`
	Params easyjson.RawMessage `json:"params"`
}

type CrashedError struct {
	ErrorMessage string
}

type EnvT map[string]string

type Handler interface {
	// Returns a channel to read the invocation result from; the channel is closed after the result is written to it.
	InvokeAsync(pid PidT, seqno SeqnoT, chkID string, ccRes CCResT, appEv AppEvT, target InvokeTarget) <-chan InvokeRet

	// Finalize cleans up allocated resources.  Any error encountered during cleanup is logged but ignored.
	Finalize()
}

type InvokeRet struct {
	Req *Request
	Err error
}

type InvokeTarget int

type PidT int // Overflow is unlikely.

type Request struct {
	Pid     PidT        `json:"pid"`
	Seqno   SeqnoT      `json:"seqno"`
	ChkID   string      `json:"chk_id"`
	Calls   []CoordCall `json:"calls"`
	Blocked bool        `json:"blocked"`
	Err     *string     `json:"err"`
}

type SeqnoT int

type TimeoutError struct{}