Flask DateTime赢得'；t使用默认的datetime.utcnow设置

我是SQLAlchemy新手，无法设置创建的日期时间。我尝试过使用许多示例中的“default”选项。我也尝试过手动设置（我已经把它注释掉了）。到目前为止，两人都没有成功。任何帮助都将不胜感激

models.py

import datetime
from flask.ext.sqlalchemy import SQLAlchemy
from werkzeug import generate_password_hash, check_password_hash

db = SQLAlchemy()

class User(db.Model):

  __tablename__    = 'users'
  uid              = db.Column(db.Integer, primary_key=True)
  firstname        = db.Column(db.String(40))
  lastname         = db.Column(db.String(40))
  email            = db.Column(db.String(120), unique=True)
  created          = db.Column(db.DateTime, default=datetime.datetime.utcnow())
  confirmed        = db.Column(db.DateTime, nullable=True)
  pwdhash          = db.Column(db.String(100))

  def __init__(self, firstname, lastname, email, password):
    self.firstname = firstname.title()
    self.lastname  = lastname.title()
    self.email     = email.lower()
    self.set_password(password)
    #self.created   = datetime.datetime.utcnow()
    self.confirmed = None

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

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

routes.py

from tasks import app
from datetime import datetime
from flask import render_template, request, flash, session, url_for, redirect
from forms import ContactForm, SignupForm, SigninForm
from flask.ext.mail import Message, Mail
from models import db, User, Tags, Tasks

@app.route('/signup', methods=['GET', 'POST'])
def signup():
  form = SignupForm()

  if 'email' in session:
    return redirect(url_for('profile')) 

  if request.method == 'POST':
    if form.validate() == False:
      return render_template('signup.html', form=form)
    else:
      newuser = User(form.firstname.data, form.lastname.data, form.email.data, form.password.data)
      db.session.add(newuser)
      db.session.commit()

      session['email'] = newuser.email
      return redirect(url_for('profile'))

  elif request.method == 'GET':
    return render_template('signup.html', form=form)

---

default

的问题在于，您正在那里立即调用

datetime.utcnow

，并且返回的值（在类定义时）始终用作默认值。您需要按如下方式传递callable本身：

#注意datetime.utcnow之后缺少括号
created=db.Column（db.DateTime，默认值=DateTime.DateTime.utcnow）

这样，SQLAlchemy将在插入行时调用

datetime.utcnow

本身