nomad: endpoint to force re-evaluation of job

nomad/job_endpoint.go

@@ -83,6 +83,61 @@ func (j *Job) Register(args *structs.JobRegisterRequest, reply *structs.JobRegis
 	return nil
 }
 
+// Evaluate is used to force a job for re-evaluation
+func (j *Job) Evaluate(args *structs.JobEvaluateRequest, reply *structs.JobRegisterResponse) error {
+	if done, err := j.srv.forward("Job.Evaluate", args, args, reply); done {
+		return err
+	}
+	defer metrics.MeasureSince([]string{"nomad", "job", "evaluate"}, time.Now())
+
+	// Validate the arguments
+	if args.JobID == "" {
+		return fmt.Errorf("missing job ID for evaluation")
+	}
+
+	// Lookup the job
+	snap, err := j.srv.fsm.State().Snapshot()
+	if err != nil {
+		return err
+	}
+	job, err := snap.GetJobByID(args.JobID)
+	if err != nil {
+		return err
+	}
+	if job == nil {
+		return fmt.Errorf("job not found")
+	}
+
+	// Create a new evaluation
+	eval := &structs.Evaluation{
+		ID:             generateUUID(),
+		Priority:       job.Priority,
+		Type:           job.Type,
+		TriggeredBy:    structs.EvalTriggerJobRegister,
+		JobID:          job.ID,
+		JobModifyIndex: job.ModifyIndex,
+		Status:         structs.EvalStatusPending,
+	}
+	update := &structs.EvalUpdateRequest{
+		Evals:        []*structs.Evaluation{eval},
+		WriteRequest: structs.WriteRequest{Region: args.Region},
+	}
+
+	// Commit this evaluation via Raft
+	_, evalIndex, err := j.srv.raftApply(structs.EvalUpdateRequestType, update)
+	if err != nil {
+		j.srv.logger.Printf("[ERR] nomad.job: Eval create failed: %v", err)
+		return err
+	}
+
+	// Setup the reply
+	reply.EvalID = eval.ID
+	reply.EvalCreateIndex = evalIndex
+	reply.JobModifyIndex = job.ModifyIndex
+	reply.Index = evalIndex
+	return nil
+}
+
 // Deregister is used to remove a job the cluster.
 func (j *Job) Deregister(args *structs.JobDeregisterRequest, reply *structs.JobDeregisterResponse) error {
 	if done, err := j.srv.forward("Job.Deregister", args, args, reply); done {

nomad/job_endpoint_test.go

@@ -161,6 +161,75 @@ func TestJobEndpoint_Register_Existing(t *testing.T) {
 	}
 }
 
+func TestJobEndpoint_Evaluate(t *testing.T) {
+	s1 := testServer(t, nil)
+	defer s1.Shutdown()
+	codec := rpcClient(t, s1)
+	testutil.WaitForLeader(t, s1.RPC)
+
+	// Create the register request
+	job := mock.Job()
+	req := &structs.JobRegisterRequest{
+		Job:          job,
+		WriteRequest: structs.WriteRequest{Region: "region1"},
+	}
+
+	// Fetch the response
+	var resp structs.JobRegisterResponse
+	if err := msgpackrpc.CallWithCodec(codec, "Job.Register", req, &resp); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	if resp.Index == 0 {
+		t.Fatalf("bad index: %d", resp.Index)
+	}
+
+	// Force a re-evaluation
+	reEval := &structs.JobEvaluateRequest{
+		JobID:        job.ID,
+		WriteRequest: structs.WriteRequest{Region: "region1"},
+	}
+
+	// Fetch the response
+	if err := msgpackrpc.CallWithCodec(codec, "Job.Evaluate", reEval, &resp); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	if resp.Index == 0 {
+		t.Fatalf("bad index: %d", resp.Index)
+	}
+
+	// Lookup the evaluation
+	state := s1.fsm.State()
+	eval, err := state.GetEvalByID(resp.EvalID)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	if eval == nil {
+		t.Fatalf("expected eval")
+	}
+	if eval.CreateIndex != resp.EvalCreateIndex {
+		t.Fatalf("index mis-match")
+	}
+
+	if eval.Priority != job.Priority {
+		t.Fatalf("bad: %#v", eval)
+	}
+	if eval.Type != job.Type {
+		t.Fatalf("bad: %#v", eval)
+	}
+	if eval.TriggeredBy != structs.EvalTriggerJobRegister {
+		t.Fatalf("bad: %#v", eval)
+	}
+	if eval.JobID != job.ID {
+		t.Fatalf("bad: %#v", eval)
+	}
+	if eval.JobModifyIndex != resp.JobModifyIndex {
+		t.Fatalf("bad: %#v", eval)
+	}
+	if eval.Status != structs.EvalStatusPending {
+		t.Fatalf("bad: %#v", eval)
+	}
+}
+
 func TestJobEndpoint_Deregister(t *testing.T) {
 	s1 := testServer(t, nil)
 	defer s1.Shutdown()

nomad/structs/structs.go

@@ -155,6 +155,12 @@ type JobDeregisterRequest struct {
 	WriteRequest
 }
 
+// JobEvaluateRequest is used when we just need to re-evaluate a target job
+type JobEvaluateRequest struct {
+	JobID string
+	WriteRequest
+}
+
 // JobSpecificRequest is used when we just need to specify a target job
 type JobSpecificRequest struct {
 	JobID string