Use containers labels instead of task labels from Docker Swarm SD (#9187) (#10311)

* Remove task labels from Docker Swarm SD (#9187)

Signed-off-by: Ujjwal Goyal <importujjwal@gmail.com>

Add container labels to Docker Swarm SD (#9187)

Signed-off-by: Ujjwal Goyal <importujjwal@gmail.com>

* Reorder labels in configuration doc

Signed-off-by: Ujjwal Goyal <importujjwal@gmail.com>

discovery/moby/tasks.go

@@ -28,14 +28,14 @@ import (
 )
 
 const (
-	swarmLabelTaskPrefix       = swarmLabel + "task_"
-	swarmLabelTaskID           = swarmLabelTaskPrefix + "id"
-	swarmLabelTaskLabelPrefix  = swarmLabelTaskPrefix + "label_"
-	swarmLabelTaskDesiredState = swarmLabelTaskPrefix + "desired_state"
-	swarmLabelTaskStatus       = swarmLabelTaskPrefix + "state"
-	swarmLabelTaskContainerID  = swarmLabelTaskPrefix + "container_id"
-	swarmLabelTaskSlot         = swarmLabelTaskPrefix + "slot"
-	swarmLabelTaskPortMode     = swarmLabelTaskPrefix + "port_publish_mode"
+	swarmLabelTaskPrefix           = swarmLabel + "task_"
+	swarmLabelTaskID               = swarmLabelTaskPrefix + "id"
+	swarmLabelTaskDesiredState     = swarmLabelTaskPrefix + "desired_state"
+	swarmLabelTaskStatus           = swarmLabelTaskPrefix + "state"
+	swarmLabelTaskContainerID      = swarmLabelTaskPrefix + "container_id"
+	swarmLabelTaskSlot             = swarmLabelTaskPrefix + "slot"
+	swarmLabelTaskPortMode         = swarmLabelTaskPrefix + "port_publish_mode"
+	swarmLabelContainerLabelPrefix = swarmLabel + "container_label_"
 )
 
 func (d *Discovery) refreshTasks(ctx context.Context) ([]*targetgroup.Group, error) {
@@ -75,9 +75,11 @@ func (d *Discovery) refreshTasks(ctx context.Context) ([]*targetgroup.Group, err
 			commonLabels[swarmLabelTaskContainerID] = s.Status.ContainerStatus.ContainerID
 		}
 
-		for k, v := range s.Labels {
-			ln := strutil.SanitizeLabelName(k)
-			commonLabels[swarmLabelTaskLabelPrefix+ln] = v
+		if s.Spec.ContainerSpec != nil {
+			for k, v := range s.Spec.ContainerSpec.Labels {
+				ln := strutil.SanitizeLabelName(k)
+				commonLabels[swarmLabelContainerLabelPrefix+ln] = v
+			}
 		}
 
 		for k, v := range serviceLabels[s.ServiceID] {

docs/configuration/configuration.md

@@ -792,10 +792,10 @@ created using the `port` parameter defined in the SD configuration.
 
 Available meta labels:
 
+* `__meta_dockerswarm_container_label_<labelname>`: each label of the container
 * `__meta_dockerswarm_task_id`: the id of the task
 * `__meta_dockerswarm_task_container_id`: the container id of the task
 * `__meta_dockerswarm_task_desired_state`: the desired state of the task
-* `__meta_dockerswarm_task_label_<labelname>`: each label of the task
 * `__meta_dockerswarm_task_slot`: the slot of the task
 * `__meta_dockerswarm_task_state`: the state of the task
 * `__meta_dockerswarm_task_port_publish_mode`: the publish mode of the task port