.factory('Lines', ['$resource', function($resource){
  return $resource('/api/lines/:lineId');
}])

.controller('Ctrl', ['$scope', 'Lines', function($scope, Lines) {
  $scope.lines = Lines.query();

  $scope.addTranslation = function(line, transForm) {
    if (transForm.$valid) {
      line.$save(function(){
        line.open = false;
        ...
      });
    }
  };
}]);

// partial.html
...
<accordion-group ng-repeat="line in lines" is-open="line.open">
...
</accordion-group>