使用文本数组的flask-sqlalchemy过滤器

Question

我正在尝试通过字符串过滤我的flask-sqlalchemy查询。 我创建字符串的过程将导致以下数组：

["user.name == 'Sid'", "user.role == 'admin'"]

它由以下内容组成：

for i in myarray:
    filter_string = "%s.%s == '%s'" % (self.model.__tablename__, i[0], i[2])
    or_filters.append(filter_string)

这是我的使用方式：

db = SQLAlchemy(app)
...
class myclass:
  def __init(self, model):
    self.model = model
    self.q = db.session.query(self.model)

  def get(self, cfg):
    ...
    # the following line works
    myfilter = [User.name == 'Sid', User.role == 'admin']
    # the following line does not work, but I need it to. How to modify into the line above?
    myfilter = ["user.name == 'Sid'", "user.role == 'admin'"]
    if myfilter is not None:
      self.q = self.apply_filter(myfilter)

    items = self.q.all()
    return items

  def apply_filter(self, ftr):
    self.q.filter(or_(*ftr))

Answer 1

Ilja有一个很好的解决方案

myfilter = getattr(self.model, i[0]).is_(i[2])
if myfilter is not None:
  self.q = self.apply_filter(myfilter)