feat(backup): add websocket for backup targets.

Ref: 5411

Signed-off-by: James Lu <james.lu@suse.com>

api/backup.go

@@ -38,14 +38,23 @@ func (s *Server) BackupTargetGet(w http.ResponseWriter, req *http.Request) error
 func (s *Server) BackupTargetList(w http.ResponseWriter, req *http.Request) error {
 	apiContext := api.GetApiContext(req)
 
-	backupTargets, err := s.m.ListBackupTargetsSorted()
+	bts, err := s.backupTargetList(apiContext)
 	if err != nil {
 		return errors.Wrap(err, "failed to list backup targets")
 	}
-	apiContext.Write(toBackupTargetCollection(backupTargets, apiContext))
+
+	apiContext.Write(bts)
 	return nil
 }
 
+func (s *Server) backupTargetList(apiContext *api.ApiContext) (*client.GenericCollection, error) {
+	bts, err := s.m.ListBackupTargetsSorted()
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to list backup target")
+	}
+	return toBackupTargetCollection(bts, apiContext), nil
+}
+
 func (s *Server) BackupTargetCreate(rw http.ResponseWriter, req *http.Request) error {
 	var input BackupTarget
 	apiContext := api.GetApiContext(req)

api/router.go

@@ -259,6 +259,10 @@ func NewRouter(s *Server) *mux.Router {
 	r.Path("/v1/ws/backupvolumes").Handler(f(schemas, backupVolumeStream))
 	r.Path("/v1/ws/{period}/backupvolumes").Handler(f(schemas, backupVolumeStream))
 
+	backupTargetStream := NewStreamHandlerFunc("backuptargets", s.wsc.NewWatcher("backupTarget"), s.backupTargetList)
+	r.Path("/v1/ws/backuptargets").Handler(f(schemas, backupTargetStream))
+	r.Path("/v1/ws/{period}/backuptargets").Handler(f(schemas, backupTargetStream))
+
 	// TODO:
 	// We haven't found a way to allow passing the volume name as a parameter to filter
 	// per-backup volume's backups change thru. WebSocket endpoint. Either by: