在Flask中查詢數據庫

Question

當我嘗試在我在下面的forms.py中創建的用戶對象上調用check_password時，我收到AttributeError: 'BaseQuery' object has no attribute 'check_password。下面是發生問題的兩條線：

user = User.query.filter_by(userID = self.userID.data) 
if user and user.check_password(self.password.data): 
    ... 

相關源代碼如下。我知道check_password()方法可行，因爲我可以從models.py內調用它。我不知道爲什麼我可以訪問用戶模型，但不能訪問check_password函數。

forms.py

...  
from .models import User 

    class LoginForm(Form): 
     ... 

     def validate(self): 
      if not Form.validate(self): 
       return False 

      ***user = User.query.filter_by(userID = self.userID.data)***  
      ***if user and user.check_password(self.password.data)***: 
       return True 
      else: 
       self.userID.errors.append("Invalid user ID or password") 
       return False 

models.py

from app import db 
from flask.ext.login import LoginManager, UserMixin 
from werkzeug import generate_password_hash, check_password_hash 

class User(UserMixin, db.Model): 
     __tablename__ = 'users' 
     id = db.Column(db.Integer, primary_key=True) 
     social_id = db.Column(db.String(64), nullable=False) #could have duplicate 
     userID = db.Column(db.String(64), nullable=False) 
     email = db.Column(db.String(64), nullable=True) 
     pwdhash = db.Column(db.String(54), nullable=True) 
     posts = db.relationship('Post', backref='author', lazy='dynamic') 

     def __init__(self, social_id, userID, email, password): 
      if social_id: 
       self.social_id = social_id #not required if not using Facebook login 
      if userID: 
       self.userID = userID 
      self.email = email.lower() 
      if password: 
       self.set_password(password) 
       assert self.check_password(password) 

     def set_password(self, password): 
      self.pwdhash = generate_password_hash(password) 

     def check_password(self, password): 
      return check_password_hash(self.pwdhash, password) 

Answer 1

User.query.filter_by()將返回查詢。如果要查詢的第一個結果需要撥打first()，即

User.query.filter_by(...).first()