Consul service meta (#6193)

* adds meta object to service in job spec, sends it to consul

* adds tests for service meta

* fix tests

* adds docs

* better hashing for service meta, use helper for copying meta when registering service

* tried to be DRY, but looks like it would be more work to use the
helper function

api/services.go

@@ -106,6 +106,7 @@ type Service struct {
 	Checks       []ServiceCheck
 	CheckRestart *CheckRestart `mapstructure:"check_restart"`
 	Connect      *ConsulConnect
+	Meta         map[string]string
 }
 
 // Canonicalize the Service by ensuring its name and address mode are set. Task

client/allocrunner/taskrunner/service_hook.go

@@ -252,6 +252,15 @@ func interpolateServices(taskEnv *taskenv.TaskEnv, services []*structs.Service)
 		service.PortLabel = taskEnv.ReplaceEnv(service.PortLabel)
 		service.Tags = taskEnv.ParseAndReplace(service.Tags)
 		service.CanaryTags = taskEnv.ParseAndReplace(service.CanaryTags)
+
+		if len(service.Meta) > 0 {
+			meta := make(map[string]string, len(service.Meta))
+			for k, v := range service.Meta {
+				meta[k] = taskEnv.ReplaceEnv(v)
+			}
+			service.Meta = meta
+		}
+
 		interpolated[i] = service
 	}
 

command/agent/consul/client.go

@@ -728,6 +728,14 @@ func (c *ServiceClient) serviceRegs(ops *operations, service *structs.Service, t
 		return nil, fmt.Errorf("invalid Consul Connect configuration for service %q: %v", service.Name, err)
 	}
 
+	meta := make(map[string]string, len(service.Meta))
+	for k, v := range service.Meta {
+		meta[k] = v
+	}
+
+	// This enables the consul UI to show that Nomad registered this service
+	meta["external-source"] = "nomad"
+
 	// Build the Consul Service registration request
 	serviceReg := &api.AgentServiceRegistration{
 		ID:      id,
@@ -735,10 +743,7 @@ func (c *ServiceClient) serviceRegs(ops *operations, service *structs.Service, t
 		Tags:    tags,
 		Address: ip,
 		Port:    port,
-		// This enables the consul UI to show that Nomad registered this service
-		Meta: map[string]string{
-			"external-source": "nomad",
-		},
+		Meta:    meta,
 		Connect: connect, // will be nil if no Connect stanza
 	}
 	ops.regServices = append(ops.regServices, serviceReg)

command/agent/job_endpoint.go

@@ -828,6 +828,7 @@ func ApiTaskToStructsTask(apiTask *api.Task, structsTask *structs.Task) {
 				Tags:        service.Tags,
 				CanaryTags:  service.CanaryTags,
 				AddressMode: service.AddressMode,
+				Meta:        helper.CopyMapStringString(service.Meta),
 			}
 
 			if l := len(service.Checks); l != 0 {
@@ -1005,6 +1006,7 @@ func ApiServicesToStructs(in []*api.Service) []*structs.Service {
 			Tags:        s.Tags,
 			CanaryTags:  s.CanaryTags,
 			AddressMode: s.AddressMode,
+			Meta:        helper.CopyMapStringString(s.Meta),
 		}
 
 		if l := len(s.Checks); l != 0 {

command/agent/job_endpoint_test.go

@@ -1507,6 +1507,9 @@ func TestJobs_ApiJobToStructsJob(t *testing.T) {
 						Tags:       []string{"a", "b"},
 						CanaryTags: []string{"d", "e"},
 						PortLabel:  "1234",
+						Meta: map[string]string{
+							"servicemeta": "foobar",
+						},
 						CheckRestart: &api.CheckRestart{
 							Limit: 4,
 							Grace: helper.TimeToPtr(11 * time.Second),
@@ -1571,6 +1574,9 @@ func TestJobs_ApiJobToStructsJob(t *testing.T) {
 								Tags:       []string{"1", "2"},
 								CanaryTags: []string{"3", "4"},
 								PortLabel:  "foo",
+								Meta: map[string]string{
+									"servicemeta": "foobar",
+								},
 								CheckRestart: &api.CheckRestart{
 									Limit: 4,
 									Grace: helper.TimeToPtr(11 * time.Second),
@@ -1845,6 +1851,9 @@ func TestJobs_ApiJobToStructsJob(t *testing.T) {
 						CanaryTags:  []string{"d", "e"},
 						PortLabel:   "1234",
 						AddressMode: "auto",
+						Meta: map[string]string{
+							"servicemeta": "foobar",
+						},
 						Checks: []*structs.ServiceCheck{
 							{
 								Name:          "bar",
@@ -1904,6 +1913,9 @@ func TestJobs_ApiJobToStructsJob(t *testing.T) {
 								CanaryTags:  []string{"3", "4"},
 								PortLabel:   "foo",
 								AddressMode: "auto",
+								Meta: map[string]string{
+									"servicemeta": "foobar",
+								},
 								Checks: []*structs.ServiceCheck{
 									{
 										Name:          "bar",

jobspec/parse_service.go

@@ -46,6 +46,7 @@ func parseService(o *ast.ObjectItem) (*api.Service, error) {
 		"address_mode",
 		"check_restart",
 		"connect",
+		"meta",
 	}
 	if err := helper.CheckHCLKeys(o.Val, valid); err != nil {
 		return nil, err
@@ -60,27 +61,28 @@ func parseService(o *ast.ObjectItem) (*api.Service, error) {
 	delete(m, "check")
 	delete(m, "check_restart")
 	delete(m, "connect")
+	delete(m, "meta")
 
 	if err := mapstructure.WeakDecode(m, &service); err != nil {
 		return nil, err
 	}
 
-	// Filter checks
-	var checkList *ast.ObjectList
+	// Filter list
+	var listVal *ast.ObjectList
 	if ot, ok := o.Val.(*ast.ObjectType); ok {
-		checkList = ot.List
+		listVal = ot.List
 	} else {
 		return nil, fmt.Errorf("'%s': should be an object", service.Name)
 	}
 
-	if co := checkList.Filter("check"); len(co.Items) > 0 {
+	if co := listVal.Filter("check"); len(co.Items) > 0 {
 		if err := parseChecks(&service, co); err != nil {
 			return nil, multierror.Prefix(err, fmt.Sprintf("'%s',", service.Name))
 		}
 	}
 
 	// Filter check_restart
-	if cro := checkList.Filter("check_restart"); len(cro.Items) > 0 {
+	if cro := listVal.Filter("check_restart"); len(cro.Items) > 0 {
 		if len(cro.Items) > 1 {
 			return nil, fmt.Errorf("check_restart '%s': cannot have more than 1 check_restart", service.Name)
 		}
@@ -93,7 +95,7 @@ func parseService(o *ast.ObjectItem) (*api.Service, error) {
 	}
 
 	// Filter connect
-	if co := checkList.Filter("connect"); len(co.Items) > 0 {
+	if co := listVal.Filter("connect"); len(co.Items) > 0 {
 		if len(co.Items) > 1 {
 			return nil, fmt.Errorf("connect '%s': cannot have more than 1 connect stanza", service.Name)
 		}
@@ -106,6 +108,20 @@ func parseService(o *ast.ObjectItem) (*api.Service, error) {
 		service.Connect = c
 	}
 
+	// Parse out meta fields. These are in HCL as a list so we need
+	// to iterate over them and merge them.
+	if metaO := listVal.Filter("meta"); len(metaO.Items) > 0 {
+		for _, o := range metaO.Elem().Items {
+			var m map[string]interface{}
+			if err := hcl.DecodeObject(&m, o.Val); err != nil {
+				return nil, err
+			}
+			if err := mapstructure.WeakDecode(m, &service.Meta); err != nil {
+				return nil, err
+			}
+		}
+	}
+
 	return &service, nil
 }
 

jobspec/parse_test.go

@@ -784,6 +784,33 @@ func TestParse(t *testing.T) {
 			},
 			false,
 		},
+		{
+			"service-meta.hcl",
+			&api.Job{
+				ID:   helper.StringToPtr("service_meta"),
+				Name: helper.StringToPtr("service_meta"),
+				Type: helper.StringToPtr("service"),
+				TaskGroups: []*api.TaskGroup{
+					{
+						Name: helper.StringToPtr("group"),
+						Tasks: []*api.Task{
+							{
+								Name: "task",
+								Services: []*api.Service{
+									{
+										Name: "http-service",
+										Meta: map[string]string{
+											"foo": "bar",
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			false,
+		},
 		{
 			"reschedule-job.hcl",
 			&api.Job{

jobspec/test-fixtures/service-meta.hcl

@@ -0,0 +1,14 @@
+job "service_meta" {
+    type = "service"
+    group "group" {
+        task "task" {
+          service {
+            name = "http-service"
+            meta {
+                foo = "bar"
+            }
+          }
+        }
+    }
+}
+

nomad/structs/services.go

@@ -324,10 +324,11 @@ type Service struct {
 	// this service.
 	AddressMode string
 
-	Tags       []string        // List of tags for the service
-	CanaryTags []string        // List of tags for the service when it is a canary
-	Checks     []*ServiceCheck // List of checks associated with the service
-	Connect    *ConsulConnect  // Consul Connect configuration
+	Tags       []string          // List of tags for the service
+	CanaryTags []string          // List of tags for the service when it is a canary
+	Checks     []*ServiceCheck   // List of checks associated with the service
+	Connect    *ConsulConnect    // Consul Connect configuration
+	Meta       map[string]string // Consul service meta
 }
 
 // Copy the stanza recursively. Returns nil if nil.
@@ -350,6 +351,8 @@ func (s *Service) Copy() *Service {
 
 	ns.Connect = s.Connect.Copy()
 
+	ns.Meta = helper.CopyMapStringString(s.Meta)
+
 	return ns
 }
 
@@ -458,6 +461,9 @@ func (s *Service) Hash(allocID, taskName string, canary bool) string {
 	for _, tag := range s.CanaryTags {
 		io.WriteString(h, tag)
 	}
+	if len(s.Meta) > 0 {
+		fmt.Fprintf(h, "%v", s.Meta)
+	}
 
 	// Vary ID on whether or not CanaryTags will be used
 	if canary {
@@ -514,6 +520,10 @@ OUTER:
 		return false
 	}
 
+	if !reflect.DeepEqual(s.Meta, o.Meta) {
+		return false
+	}
+
 	if !helper.CompareSliceSetString(s.Tags, o.Tags) {
 		return false
 	}

website/source/api/jobs.html.md

@@ -146,6 +146,9 @@ The table below shows this endpoint's support for
                         "global",
                         "cache"
                     ],
+                    "Meta": {
+                      "meta": "for my service"
+                    },
                     "PortLabel": "db",
                     "AddressMode": "",
                     "Checks": [{

website/source/api/json-jobs.html.md

@@ -56,6 +56,9 @@ Below is the JSON representation of the job outputted by `$ nomad init`:
                         "global",
                         "cache"
                     ],
+                    "Meta": {
+                      "meta": "for my service",
+                    },
                     "PortLabel": "db",
                     "AddressMode": "",
                     "Checks": [{
@@ -400,6 +403,9 @@ The `Task` object supports the following keys:
 
      - `Tags`: A list of string tags associated with this Service. String
        interpolation is supported in tags.
+      
+     - `Meta`: A key-value map that annotates the Consul service with
+       user-defined metadata. String interpolation is supported in meta.
 
      - `CanaryTags`: A list of string tags associated with this Service while it
        is a canary. Once the canary is promoted, the registered tags will be

website/source/docs/job-specification/service.html.md

@@ -33,6 +33,10 @@ job "docs" {
 
         port = "db"
 
+        meta {
+          meta = "for your service"
+        }
+
         check {
           type     = "tcp"
           port     = "db"
@@ -135,6 +139,9 @@ does not automatically enable service discovery.
     implemented for Docker and rkt.
 
   - `host` - Use the host IP and port.
+  
+- `meta` <code>([Meta][]: nil)</code> - Specifies a key-value map that annotates
+  the Consul service with user-defined metadata.
 
 ### `check` Parameters