job_state.go

package registry

import (
	"path"
	"time"

	"github.com/coreos/fleet/etcd"
	"github.com/coreos/fleet/job"
	"github.com/coreos/fleet/unit"
)

// determineJobState decides what the State field of a Job object should
// be, based on three parameters:
//  - heartbeat should be the machine ID that is known to have recently
//    heartbeaten (see UnitHeartbeat) the Unit.
//  - tgt should be the machine ID to which the Job is currently scheduled
//  - us should be the most recent UnitState
func determineJobState(heartbeat, tgt string, us *unit.UnitState) (state job.JobState) {
	state = job.JobStateInactive

	if tgt == "" || us == nil {
		return
	}

	state = job.JobStateLoaded

	if heartbeat != tgt {
		return
	}

	state = job.JobStateLaunched
	return
}

func (r *EtcdRegistry) UnitHeartbeat(name, machID string, ttl time.Duration) error {
	req := etcd.Set{
		Key:   r.jobHeartbeatPath(name),
		Value: machID,
		TTL:   ttl,
	}
	_, err := r.etcd.Do(&req)
	return err
}

func (r *EtcdRegistry) ClearUnitHeartbeat(name string) {
	req := etcd.Delete{
		Key: r.jobHeartbeatPath(name),
	}
	r.etcd.Do(&req)
}

func (r *EtcdRegistry) jobHeartbeatPath(jobName string) string {
	return path.Join(r.keyPrefix, jobPrefix, jobName, "job-state")
}