feat: target workflow runs by tag selector

server/internal/services/workflow_runner.go

@@ -22,17 +22,14 @@ func TriggerWorkflow(instanceID, workflowID, actor string) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	if len(wf.TargetServerIDs) == 0 {
-		return "", fmt.Errorf("workflow has no target servers")
+	targets, err := ResolveTargets(instanceID, wf.TargetServerIDs, wf.TargetTags)
+	if err != nil {
+		return "", err
 	}
 	if len(wf.Steps) == 0 {
 		return "", fmt.Errorf("workflow has no steps")
 	}
 
-	if err := validateTargetServers(instanceID, wf.TargetServerIDs); err != nil {
-		return "", err
-	}
-
 	ctx, cancel := wfCtx()
 	running := db.Col("workflow_runs").FindOne(ctx, bson.M{"instance_id": instanceID, "workflow_id": workflowID, "status": "running"})
 	cancel()
@@ -54,14 +51,10 @@ func TriggerWorkflow(instanceID, workflowID, actor string) (string, error) {
 		Status:      "running",
 		TriggeredBy: actor,
 		StartedAt:   time.Now(),
-		ServerRuns:  make([]models.ServerRun, 0, len(wf.TargetServerIDs)),
+		ServerRuns:  make([]models.ServerRun, 0, len(targets)),
 	}
-	for _, sid := range wf.TargetServerIDs {
-		hostname := sid
-		if s, e := getServerByID(sid); e == nil {
-			hostname = s.Hostname
-		}
-		sr := models.ServerRun{ServerID: sid, Hostname: hostname, Status: "queued", RunEnv: map[string]string{}}
+	for _, srv := range targets {
+		sr := models.ServerRun{ServerID: srv.ServerID, Hostname: srv.Hostname, Status: "queued", RunEnv: map[string]string{}}
 		for _, rs := range resolved {
 			sr.Steps = append(sr.Steps, models.StepRun{Order: rs.Order, Name: rs.Name, Status: "queued", OutputEnv: map[string]string{}})
 		}

server/internal/services/workflows.go

@@ -249,6 +249,9 @@ func CreateWorkflow(instanceID string, w models.Workflow) (*models.Workflow, err
 	if err := ValidateWorkflow(w); err != nil {
 		return nil, err
 	}
+	if err := ValidateTags(w.TargetTags); err != nil {
+		return nil, err
+	}
 	if err := validateTargetServers(instanceID, w.TargetServerIDs); err != nil {
 		return nil, err
 	}
@@ -265,6 +268,9 @@ func UpdateWorkflow(instanceID, id string, w models.Workflow) error {
 	if err := ValidateWorkflow(w); err != nil {
 		return err
 	}
+	if err := ValidateTags(w.TargetTags); err != nil {
+		return err
+	}
 	if err := validateTargetServers(instanceID, w.TargetServerIDs); err != nil {
 		return err
 	}
@@ -272,6 +278,7 @@ func UpdateWorkflow(instanceID, id string, w models.Workflow) error {
 	_, err := db.Col("workflows").UpdateOne(ctx, bson.M{"workflow_id": id, "instance_id": instanceID}, bson.M{"$set": bson.M{
 		"name":              w.Name,
 		"target_server_ids": w.TargetServerIDs,
+		"target_tags":       w.TargetTags,
 		"steps":             w.Steps,
 		"updated_at":        time.Now(),
 	}})