MongoEngine Python AttributeError

Question

我试图在我的应用程序中使用mongodb，我创建了一个Player Class实例，如：

class Player(mongoengine.Document):

def __init__(self,name=None,hschool=None,gradclass=None,position=None,
             height=None,weight=None,main_pos=None,side_pos=None,arm=None,
            extVelo=None,infieldVelo=None,outfieldVelo=None,popTime=None,
            catcherVelo=None,sixtyYard=None,fastBallVelo=None,maxfBallVelo=None,
            curveball=None,changeup=None,slider=None,splitter=None,cutter=None,
            knuckle=None,fork=None,profile_url=None):
     self._name = mongoengine.StringField()
    self.p_name = name
    self._hschool = mongoengine.StringField()
    self._gradclass = mongoengine.StringField()
    self._position = mongoengine.StringField()
    self._main_pos = mongoengine.StringField()
    self._side_pos = mongoengine.StringField()
    self._arm = mongoengine.StringField()
    self._height = mongoengine.StringField()
    self._weight = mongoengine.StringField()
    self._extVelo= mongoengine.StringField()
    self.heightFlag = False
    self._infieldVelo = mongoengine.StringField()
    self._outfieldVelo = mongoengine.StringField()
    self._popTime = mongoengine.StringField()
    self._catcherVelo = mongoengine.StringField()
    self._sixtyYard=mongoengine.StringField()
    self._fastBallVelo = mongoengine.StringField()
    self._maxfBallVelo = mongoengine.StringField()
    self._curveball = mongoengine.StringField()
    self._changeup = mongoengine.StringField()
    self._slider = mongoengine.StringField()
    self._splitter = mongoengine.StringField()
    self._cutter = mongoengine.StringField()
    self._knuckle = mongoengine.StringField()
    self._fork = mongoengine.StringField()
    self._profile_url = mongoengine.StringField()
    self.p_profile_url = profile_url

在此之后，我为Player属性设置了setter和getter，我将所有这些属性设置为字符串。做完所有这些工作之后，我想把这个播放器实例保存到数据库中，这样我以后就可以到达它们了。在我的主要python文件中，我有以下代码块：

def LoadData_click(url):
    p_arr=[]
    # javascript func for clearing the list here
    try:
        table1_string,table2_string,soup,page_title = get_data(url)
    except Exception as e:
        print(e)     
        return
    p_arr = get_roster(soup)
    print('button worked')
    for i,p in enumerate(p_arr):
        print(i+1/len(p_arr)*100)
        eel.progressBarUpdate(int((i+1)/len(p_arr)*100))
        set_position(p,table2_string)
        set_pitching(p,table1_string)
        set_link_props(p)
        p.save()
        # add Item to list
    return p_arr


if __name__ == "__main__":
    mongoengine.register_connection(alias='core',name='database')

当我运行主应用程序时，它会给出以下错误：

文件"c:\Users\tolga\Desktop\PlayerEditorJS\main.py"，第33行，LoadData_click p.save() File "C:\Python\lib\site-packages\mongoengine\document.py"，第369行，保存self.validate(clean=clean)文件"C:\Python\lib\site-packages\mongoengine\base\document.py"，第384行，文件"C:\Python\lib\site-packages\mongoengine\base\document.py"，第384行，以self._data.get(名称)表示名称(在self._fields_ordered中)] AttributeError：_dynamic_fields

Answer 1

这不是使用MongoEngine的方式，您的类必须从Document基类继承，如果您不使用类，并且实例将丢失MongoEngine所需的大多数内部部件来正常工作。

编辑：您还必须将字段定义为类属性，而不是在构造函数中。这是因为场景后面的元类( Document)是如何工作的，当类被解释时，它会扫描类属性，这就是它希望在哪里找到您的字段。

确保检查来自自述文件和文档的示例

例如：

from mongoengine import Document, StringField, IntField

class Player(Document):
    name = StringField()
    height = IntField()