ReferenceField 和 Wtforms答案

【问题标题】：ReferenceField and WtformsReferenceField 和 Wtforms
【发布时间】：2014-08-11 00:31:49
【问题描述】：

我遇到了 mongoengine 和 wtforms 的连接问题。

我尝试使用Role class 将权限赋予User class，但我无法将Role class 外键赋予User class

这是我的代码：

# On class File
from mongoengine import Document, StringField, ReferenceField

class User(Document):
    username = StringField(unique=True)
    password = StringField()
    role = RefrenceField(Role, default=Role.objects.get(num=3))

class Role(Document):
    num = IntField()
    name = StringField()

# On form File 
from wtforms import Form, StringField, SelectField

class UserEditForm(Form):
    username = StringField(u'Username', [validators.required()]
    role = SelectField(u'Role', [validators.required()], choices=[(r.id, r.name) for r in Role.objects])

保存时，我收到此错误消息：

ValidationError: ValidationError (User:53a14fb0cdc4674abf452f2d) (A ReferenceField only accepts DBRef or documents: ['role'])

我尝试将r.id 替换为r 和r._object_key()，但没有结果

谢谢，

【问题讨论】：

标签： python flask mongoengine flask-wtforms flask-mongoengine

【解决方案1】：

我找到了答案：SelectField 没有为ReferenceField 返回好的类型元素。

这是我的新代码：

# form File
class UserEditForm(Form):
  username = StringField(u'Username', [validators.required()])
  role = SelectField(u'Role', [validators.required()], choices=[(r.num, r.name) for r in Role.objects], coerce=int)

# Controller class
class EditUser(MethodView):
  def get_context(self, id):
    usr = User.objects.get(id=id)
    form = UserEditForm(request.form, usr)
    return {"usr": usr, "form": form}
  def post(self, id):
   context = self.get_context(id)
   form = context.get("form")
   if form.validate():
     usr = context.get("usr")
     form.populate_obj(usr)
     usr.role = Role.objects.get(num=form.role.data)
     usr.save()
     return redirect("/user_edit/" + id)
   return response("form error validation")

祝你有美好的一天

【讨论】：