Making the Job expand all service names during registration

api/tasks.go

@@ -1,8 +1,6 @@
 package api
 
 import (
-	"fmt"
-	"github.com/hashicorp/nomad/helper/args"
 	"time"
 )
 
@@ -44,16 +42,6 @@ type Service struct {
 	Checks    []ServiceCheck
 }
 
-func (s *Service) ExpandName(job string, taskGroup string, task string) {
-	s.Name = args.ReplaceEnv(s.Name, map[string]string{
-		"JOB":       job,
-		"TASKGROUP": taskGroup,
-		"TASK":      task,
-		"BASE":      fmt.Sprintf("%s-%s-%s", job, taskGroup, task),
-	},
-	)
-}
-
 // TaskGroup is the unit of scheduling.
 type TaskGroup struct {
 	Name          string

api/tasks_test.go

@@ -218,37 +218,3 @@ func TestTask_Constrain(t *testing.T) {
 		t.Fatalf("expect: %#v, got: %#v", expect, task.Constraints)
 	}
 }
-
-func TestService_Expand_Name(t *testing.T) {
-	job := "example"
-	taskGroup := "cache"
-	task := "redis"
-
-	s := Service{
-		Name: "${TASK}-db",
-	}
-
-	s.ExpandName(job, taskGroup, task)
-	if s.Name != "redis-db" {
-		t.Fatalf("Expected name: %v, Actual: %v", "redis-db", s.Name)
-	}
-
-	s.Name = "db"
-	s.ExpandName(job, taskGroup, task)
-	if s.Name != "db" {
-		t.Fatalf("Expected name: %v, Actual: %v", "redis-db", s.Name)
-	}
-
-	s.Name = "${JOB}-${TASKGROUP}-${TASK}-db"
-	s.ExpandName(job, taskGroup, task)
-	if s.Name != "example-cache-redis-db" {
-		t.Fatalf("Expected name: %v, Actual: %v", "expample-cache-redis-db", s.Name)
-	}
-
-	s.Name = "${BASE}-db"
-	s.ExpandName(job, taskGroup, task)
-	if s.Name != "example-cache-redis-db" {
-		t.Fatalf("Expected name: %v, Actual: %v", "expample-cache-redis-db", s.Name)
-	}
-
-}

nomad/job_endpoint.go

@@ -28,6 +28,9 @@ func (j *Job) Register(args *structs.JobRegisterRequest, reply *structs.JobRegis
 	if err := args.Job.Validate(); err != nil {
 		return err
 	}
+
+	args.Job.ExpandAllServiceNames()
+
 	if args.Job.Type == structs.JobTypeCore {
 		return fmt.Errorf("job type cannot be core")
 	}

nomad/job_endpoint_test.go

@@ -47,6 +47,10 @@ func TestJobEndpoint_Register(t *testing.T) {
 	if out.CreateIndex != resp.JobModifyIndex {
 		t.Fatalf("index mis-match")
 	}
+	serviceName := out.TaskGroups[0].Tasks[0].Services[0].Name
+	if serviceName != "web-frontend" {
+		t.Fatalf("Expected Service Name: %s, Actual: %s", serviceName)
+	}
 
 	// Lookup the evaluation
 	eval, err := state.EvalByID(resp.EvalID)

nomad/mock/mock.go

@@ -90,6 +90,12 @@ func Job() *structs.Job {
 						Env: map[string]string{
 							"FOO": "bar",
 						},
+						Services: []*structs.Service{
+							{
+								Name:      "${TASK}-frontend",
+								PortLabel: "http",
+							},
+						},
 						Resources: &structs.Resources{
 							CPU:      500,
 							MemoryMB: 256,

nomad/structs/structs.go

@@ -14,6 +14,7 @@ import (
 	"github.com/hashicorp/go-msgpack/codec"
 	"github.com/hashicorp/go-multierror"
 	"github.com/hashicorp/go-version"
+	"github.com/hashicorp/nomad/helper/args"
 )
 
 var (
@@ -774,6 +775,14 @@ type Job struct {
 	ModifyIndex uint64
 }
 
+// ExpandAllServiceNames traverses all Task Groups and makes them
+// interpolate Job, Task group and Task names in all Service names
+func (j *Job) ExpandAllServiceNames() {
+	for _, tg := range j.TaskGroups {
+		tg.ExpandAllServiceNames(j.Name)
+	}
+}
+
 // Validate is used to sanity check a job input
 func (j *Job) Validate() error {
 	var mErr multierror.Error
@@ -942,6 +951,14 @@ type TaskGroup struct {
 	Meta map[string]string
 }
 
+// ExpandAllServiceNames traverses over all Tasks and makes them to interpolate
+// values of Job, Task Group and Task names in all Service Names
+func (tg *TaskGroup) ExpandAllServiceNames(job string) {
+	for _, task := range tg.Tasks {
+		task.ExpandAllServiceNames(job, tg.Name)
+	}
+}
+
 // Validate is used to sanity check a task group
 func (tg *TaskGroup) Validate() error {
 	var mErr multierror.Error
@@ -1025,6 +1042,16 @@ type ServiceCheck struct {
 	Timeout  time.Duration // Timeout of the response from the check before consul fails the check
 }
 
+func (s *Service) ExpandName(job string, taskGroup string, task string) {
+	s.Name = args.ReplaceEnv(s.Name, map[string]string{
+		"JOB":       job,
+		"TASKGROUP": taskGroup,
+		"TASK":      task,
+		"BASE":      fmt.Sprintf("%s-%s-%s", job, taskGroup, task),
+	},
+	)
+}
+
 func (sc *ServiceCheck) Validate() error {
 	t := strings.ToLower(sc.Type)
 	if t != ServiceCheckTCP && t != ServiceCheckHTTP {
@@ -1109,6 +1136,14 @@ type Task struct {
 	Meta map[string]string
 }
 
+// ExpandAllServiceNames interpolates values of Job, Task Group
+// and Tasks in all the service Names of a Task
+func (t *Task) ExpandAllServiceNames(job string, taskGroup string) {
+	for _, service := range t.Services {
+		service.ExpandName(job, taskGroup, t.Name)
+	}
+}
+
 func (t *Task) GoString() string {
 	return fmt.Sprintf("*%#v", *t)
 }

nomad/structs/structs_test.go

@@ -405,3 +405,82 @@ func TestDistinctCheckId(t *testing.T) {
 	}
 
 }
+
+func TestService_Expand_Name(t *testing.T) {
+	job := "example"
+	taskGroup := "cache"
+	task := "redis"
+
+	s := Service{
+		Name: "${TASK}-db",
+	}
+
+	s.ExpandName(job, taskGroup, task)
+	if s.Name != "redis-db" {
+		t.Fatalf("Expected name: %v, Actual: %v", "redis-db", s.Name)
+	}
+
+	s.Name = "db"
+	s.ExpandName(job, taskGroup, task)
+	if s.Name != "db" {
+		t.Fatalf("Expected name: %v, Actual: %v", "redis-db", s.Name)
+	}
+
+	s.Name = "${JOB}-${TASKGROUP}-${TASK}-db"
+	s.ExpandName(job, taskGroup, task)
+	if s.Name != "example-cache-redis-db" {
+		t.Fatalf("Expected name: %v, Actual: %v", "expample-cache-redis-db", s.Name)
+	}
+
+	s.Name = "${BASE}-db"
+	s.ExpandName(job, taskGroup, task)
+	if s.Name != "example-cache-redis-db" {
+		t.Fatalf("Expected name: %v, Actual: %v", "expample-cache-redis-db", s.Name)
+	}
+
+}
+
+func TestJob_ExpandServiceNames(t *testing.T) {
+	j := &Job{
+		Name: "my-job",
+		TaskGroups: []*TaskGroup{
+			&TaskGroup{
+				Name: "web",
+				Tasks: []*Task{
+					{
+						Name: "frontend",
+						Services: []*Service{
+							{
+								Name: "${BASE}-default",
+							},
+							{
+								Name: "jmx",
+							},
+						},
+					},
+				},
+			},
+			&TaskGroup{
+				Name: "admin",
+				Tasks: []*Task{
+					{
+						Name: "admin-web",
+					},
+				},
+			},
+		},
+	}
+
+	j.ExpandAllServiceNames()
+
+	service1Name := j.TaskGroups[0].Tasks[0].Services[0].Name
+	if service1Name != "my-job-web-frontend-default" {
+		t.Fatalf("Expected Service Name: %s, Actual: %s", "my-job-web-frontend-default", service1Name)
+	}
+
+	service2Name := j.TaskGroups[0].Tasks[0].Services[1].Name
+	if service2Name != "jmx" {
+		t.Fatalf("Expected Service Name: %s, Actual: %s", "jmx", service2Name)
+	}
+
+}