Question

我在我的类方法中需要一些OR过滤，但我觉得这段代码非常糟糕。这应该是怎么回事？或者我可以设计得更好一点吗？

class FooBar:
  @classmethod
  def get_current_objects(cls, role='passenger',
                          add_params=None, offset=0, limit=10):
     """
     The logic behind this is to return cls.objects with filters
     defined in params var, but I stumbled accross
     the need to use OR in the query, whilst keeping some `add_params`
     in `params` var.
     """
     params = {}
     # ... here are some 'params', lots of code I need to keep, skipped ...
     if add_params:
        # this piece below feels awkward
        for k, v in add_params.copy().iteritems():
            if (v == True) and (role == 'passenger'):
                add_args.append(Q(**{k: True}) | Q(**{k: False}))
                del add_params[k]
            elif (v == False) and (role == 'driver'):
                add_args.append(Q(**{k: True}) | Q(**{k: False}))
                del add_params[k]
            elif (type(v) == str) and (role == 'passenger'):
                add_args.append(Q(**{k: v}) | Q(**{k: u''}))
                del add_params[k]
            elif (type(v) == str) and (role == 'driver'):
                add_args.append(Q(**{k: v}) | Q(**{k: u''}))
                del add_params[k]
        params.update(add_params)
    # -----------------------------
    return cls.objects.filter(*add_args, **params)[offset:offset + limit]

在这种情况下我怎么不重复自己？

Answer 1

我不完全确定语法，但这就是我写它的方式。

 if add_params:
    # this piece below feels awkward
    for k, v in add_params.copy().iteritems():
        if ((v == true) and (role == 'passenger'))          # edited the true/false in
        or ((v == false) and (role == 'driver')):
            add_args.append(Q(**{k: True}) | Q(**{k: False}))
            del add_params[k]

        elif (type(v) == str)                    # (x or y) and (x or z) -> x and (y or z)
        and ((role == 'passenger') or (role == 'driver')):
            add_args.append(Q(**{k: v}) | Q(**{k: u''}))
            del add_params[k]

    params.update(add_params)
# -----------------------------
return cls.objects.filter(*add_args, **params)[offset:offset + limit]

这段代码是否可以设计明智？

1 个答案: