WIP

nomad/leader.go

@@ -774,11 +774,14 @@ func (s *Server) restorePeriodicDispatcher() error {
 			continue
 		}
 
-		if _, err := s.periodicDispatcher.ForceRun(job.Namespace, job.ID); err != nil {
+		eval, err := s.periodicDispatcher.ForceRun(job.Namespace, job.ID)
+		if err != nil {
 			logger.Error("force run of periodic job failed", "job", job.NamespacedID(), "error", err)
 			return fmt.Errorf("force run of periodic job %q failed: %v", job.NamespacedID(), err)
 		}
-		logger.Debug("periodic job force runned during leadership establishment", "job", job.NamespacedID())
+		if eval != nil {
+			logger.Debug("periodic job force ran during leadership establishment", "job", job.NamespacedID())
+		}
 	}
 
 	return nil

nomad/periodic.go

@@ -295,6 +295,21 @@ func (p *PeriodicDispatch) ForceRun(namespace, jobID string) (*structs.Evaluatio
 		return nil, fmt.Errorf("can't force run non-tracked job %q (%s)", jobID, namespace)
 	}
 
+	if job.Periodic.ProhibitOverlap {
+		running, err := p.dispatcher.RunningChildren(job)
+		if err != nil {
+			p.logger.Error("failed to determine if periodic job has running children", "job", job.NamespacedID(), "error", err)
+			p.l.Unlock()
+			return nil, nil
+		}
+
+		if running {
+			p.logger.Debug("skipping launch of periodic job because job prohibits overlap", "job", job.NamespacedID())
+			p.l.Unlock()
+			return nil, nil
+		}
+	}
+
 	p.l.Unlock()
 	return p.createEval(job, time.Now().In(job.Periodic.GetLocation()))
 }
@@ -367,7 +382,7 @@ func (p *PeriodicDispatch) dispatch(job *structs.Job, launchTime time.Time) {
 
 // nextLaunch returns the next job to launch and when it should be launched. If
 // the next job can't be determined, an error is returned. If the dispatcher is
-// stopped, a nil job will be returned.
+// stopped, a nil job will be returned.	
 func (p *PeriodicDispatch) nextLaunch() (*structs.Job, time.Time) {
 	// If there is nothing wait for an update.
 	p.l.RLock()

nomad/periodic_endpoint.go

@@ -1,6 +1,7 @@
 package nomad
 
 import (
+	"errors"
 	"fmt"
 	"time"
 
@@ -72,6 +73,9 @@ func (p *Periodic) Force(args *structs.PeriodicForceRequest, reply *structs.Peri
 	if err != nil {
 		return fmt.Errorf("force launch for job %q failed: %v", job.ID, err)
 	}
+	if eval == nil {
+		return errors.New("you're fucking dumb")
+	}
 
 	reply.EvalID = eval.ID
 	reply.EvalCreateIndex = eval.CreateIndex