我遇到了SQLALCHEMY的问题，我实际上是使用FLASK micro-framework创建了我的博客，并在digitalocean.com上运行
我已经安装了运行博客所需的所有要求，uwsgi运行得非常好，但是当我启动apache时，它给出了一个错误说：
InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Original exception was: Multiple classes found for path "Category" in the registry of this declarative base. Please use a fully module-qualified path.
我现在实际上不知道为什么会出现这个错误，实际上在我的本地主机上，博客的效果非常好。
这是型号代码：
from flask_blog import db, uploaded_images, uploaded_book, uploaded_video, app
from datetime import datetime
import sys
if sys.version_info >= (3, 0):
enable_search = False
else:
enable_search = True
import flask.ext.whooshalchemy as whooshalchemy
class Blog(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(80))
admin = db.Column(db.Integer, db.ForeignKey('user.id'))
def __init__(self, name, admin):
self.name = name
self.admin = admin
def __repr__(self):
return "<Name %r>" %self.name
class Post(db.Model):
__searchable__ = ['body']
id = db.Column(db.Integer, primary_key=True)
blog_id = db.Column(db.Integer, db.ForeignKey('blog.id'))
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
title = db.Column(db.String(80))
body = db.Column(db.String(140))
image = db.Column(db.String(255))
book = db.Column(db.String(255))
price = db.Column(db.Float)
video = db.Column(db.String(255))
slug = db.Column(db.String(256), unique=True)
publish_date = db.Column(db.DateTime)
live = db.Column(db.Boolean)
category_id = db.Column(db.Integer, db.ForeignKey('category.id'))
category = db.relationship('Category', backref=db.backref('posts', lazy='dynamic'))
comments = db.relationship('Comment', backref='post', lazy='dynamic')
@property
def imgsrc(self):
return uploaded_images.url(self.image)
@property
def booksrc(self):
return uploaded_book.url(self.book)
@property
def videosrc(self):
return uploaded_video.url(self.video)
def __init__(self, blog, author, title, body, category, slug, image=None, book=None, video=None, publish_date=None, live=True):
self.blog_id = blog.id
self.user_id = author.id
self.title = title
self.body = body
self.category = category
self.slug = slug
self.image = image
self.book = book
self.video = video
if publish_date is None:
self.publish_date = datetime.utcnow()
self.live = live
def __repr__(self):
return "<Post %r>" % self.title
class Purchase(db.Model):
uuid = db.Column(db.String(128), primary_key=True)
email = db.Column(db.String(50))
product_id = db.Column(db.Integer, db.ForeignKey('post.id'))
product = db.relationship(Post)
downloads_left = db.Column(db.Integer, default=5)
sold_at = db.Column(db.DateTime, default=datetime.now)
def sell_date(self):
return self.sold_at.date()
def __str__(self):
return '{} bought by {}'.format(self.product.name, self.email)
class Category(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(50))
def __init__(self, name):
self.name = name
def __repr__(self):
return self.name
class Comment(db.Model):
__tablename__ = 'comments'
id = db.Column(db.Integer, primary_key=True)
body = db.Column(db.Text)
body_html = db.Column(db.Text)
timestamp = db.Column(db.DateTime, index=True, default=datetime.utcnow)
disabled = db.Column(db.Boolean)
author_id = db.Column(db.Integer, db.ForeignKey('user.id'))
post_id = db.Column(db.Integer, db.ForeignKey('post.id'))
@staticmethod
def on_changed_body(target, value, oldvalue, initiator):
allowed_tags = ['a', 'abbr', 'acronym', 'b', 'code', 'em', 'i',
'strong']
target.body_html = bleach.linkify(bleach.clean(
markdown(value, output_format='html'),
tags=allowed_tags, strip=True))
db.event.listen(Comment.body, 'set', Comment.on_changed_body)
if enable_search:
whooshalchemy.whoosh_index(app, Post)
还有views.py片段：
@app.route('/')
@app.route('/index/')
@app.route('/index/<int:page>')
def index(page=1):
blog = Blog.query.first()
posts = Post.query.filter_by(live=False).order_by(Post.publish_date.desc()).paginate(page, POSTS_PER_PAGE, False)
cates = Category.query.all()
execlusives = Post.query.join(Category, Category.id == Post.category_id).filter(Category.name == 'exclusives').filter(Post.live == True).order_by(Post.publish_date.desc()).all()
clever = Post.query.join(Category, Category.id == Post.category_id).filter(Category.name == 'clever').filter(Post.live == True).order_by(Post.publish_date.desc()).all()
return render_template('blog/index.html', blog=blog, posts=posts, cates=cates, execlusives=execlusives,clever=clever)
以下是调试器的更多信息：
Traceback (most recent call last)
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1836, in __call__
return self.wsgi_app(environ, start_response)
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1820, in wsgi_app
response = self.make_response(self.handle_exception(e))
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1403, in handle_exception
reraise(exc_type, exc_value, tb)
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1817, in wsgi_app
response = self.full_dispatch_request()
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1477, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1381, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1475, in full_dispatch_request
rv = self.dispatch_request()
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1461, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/var/www/FlaskApp/FlaskApp/blog/views.py", line 23, in index
blog = Blog.query.first()
File "/usr/local/lib/python2.7/dist-packages/flask_sqlalchemy/__init__.py", line 498, in __get__
mapper = orm.class_mapper(type)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/base.py", line 421, in class_mapper
mapper = _inspect_mapped_class(class_, configure=configure)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/base.py", line 400, in _inspect_mapped_class
mapper._configure_all()
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/mapper.py", line 1167, in _configure_all
configure_mappers()
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/mapper.py", line 2765, in configure_mappers
raise e
InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Original exception was: Multiple classes found for path "Category" in the registry of this declarative base. Please use a fully module-qualified path.
最终，如果有人知道从哪里开始编辑代码，那将非常感谢，谢谢:)。