我正在关注part 8 of the Flask Mega tutorial，并且已经检查我的密码与作者提供的密码相同，可以在here上找到。
我的问题是我可以这样通过单元测试：
#!/usr/bin/env python
from datetime import datetime, timedelta
import unittest
from app import app, db
from app.models import User, Post
class UserModelCase(unittest.TestCase):
def setUp(self):
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite://'
db.create_all()
def tearDown(self):
db.session.remove()
db.drop_all()
def test_password_hashing(self):
u = User(username='susan')
u.set_password('cat')
self.assertFalse(u.check_password('dog'))
self.assertTrue(u.check_password('cat'))
def test_avatar(self):
u = User(username='john', email='john@example.com')
self.assertEqual(u.avatar(128), ('https://www.gravatar.com/avatar/'
'd4c74594d841139328695756648b6bd6'
'?d=identicon&s=128'))
def test_follow(self):
u1 = User(username='john', email='john@example.com')
u2 = User(username='susan', email='susan@example.com')
db.session.add(u1)
db.session.add(u2)
db.session.commit()
self.assertEqual(u1.followed.all(), [])
self.assertEqual(u1.followers.all(), [])
u1.follow(u2)
db.session.commit()
self.assertTrue(u1.is_following(u2))
self.assertEqual(u1.followed.count(), 1)
self.assertEqual(u1.followed.first().username, 'susan')
self.assertEqual(u2.followers.count(), 1)
self.assertEqual(u2.followers.first().username, 'john')
u1.unfollow(u2)
db.session.commit()
self.assertFalse(u1.is_following(u2))
self.assertEqual(u1.followed.count(), 0)
self.assertEqual(u2.followers.count(), 0)
def test_follow_posts(self):
# create four users
u1 = User(username='john', email='john@example.com')
u2 = User(username='susan', email='susan@example.com')
u3 = User(username='mary', email='mary@example.com')
u4 = User(username='david', email='david@example.com')
db.session.add_all([u1, u2, u3, u4])
# create four posts
now = datetime.utcnow()
p1 = Post(body="post from john", author=u1,
timestamp=now + timedelta(seconds=1))
p2 = Post(body="post from susan", author=u2,
timestamp=now + timedelta(seconds=4))
p3 = Post(body="post from mary", author=u3,
timestamp=now + timedelta(seconds=3))
p4 = Post(body="post from david", author=u4,
timestamp=now + timedelta(seconds=2))
db.session.add_all([p1, p2, p3, p4])
db.session.commit()
# setup the followers
u1.follow(u2) # john follows susan
u1.follow(u4) # john follows david
u2.follow(u3) # susan follows mary
u3.follow(u4) # mary follows david
db.session.commit()
# check the followed posts of each user
f1 = u1.followed_posts().all()
f2 = u2.followed_posts().all()
f3 = u3.followed_posts().all()
f4 = u4.followed_posts().all()
self.assertEqual(f1, [p2, p4, p1])
self.assertEqual(f2, [p2, p3])
self.assertEqual(f3, [p3, p4])
self.assertEqual(f4, [p4])
if __name__ == '__main__':
unittest.main(verbosity=2)
但是当我运行该应用程序并尝试登录时，它引发了一些错误。这是错误的完整记录：
Exception on /login [POST]
Traceback (most recent call last):
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 1244, in _execute_context
cursor, statement, parameters, context
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/default.py", line 552, in do_execute
cursor.execute(statement, parameters)
sqlite3.OperationalError: no such table: user
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/app.py", line 2292, in wsgi_app
response = self.full_dispatch_request()
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/app.py", line 1815, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/app.py", line 1718, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/_compat.py", line 35, in reraise
raise value
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/app.py", line 1813, in full_dispatch_request
rv = self.dispatch_request()
File "/anaconda3/envs/flask/lib/python3.6/site-packages/flask/app.py", line 1799, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/Users/sshu/Documents/stuff/microblog/app/routes.py", line 40, in login
user = User.query.filter_by(username=form.username.data).first()
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/orm/query.py", line 3215, in first
ret = list(self[0:1])
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/orm/query.py", line 3007, in __getitem__
return list(res)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/orm/query.py", line 3317, in __iter__
return self._execute_and_instances(context)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/orm/query.py", line 3342, in _execute_and_instances
result = conn.execute(querycontext.statement, self._params)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 988, in execute
return meth(self, multiparams, params)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/sql/elements.py", line 287, in _execute_on_connection
return connection._execute_clauseelement(self, multiparams, params)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 1107, in _execute_clauseelement
distilled_params,
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 1248, in _execute_context
e, statement, parameters, cursor, context
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 1466, in _handle_dbapi_exception
util.raise_from_cause(sqlalchemy_exception, exc_info)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/util/compat.py", line 383, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb, cause=cause)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/util/compat.py", line 128, in reraise
raise value.with_traceback(tb)
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/base.py", line 1244, in _execute_context
cursor, statement, parameters, context
File "/anaconda3/envs/flask/lib/python3.6/site-packages/sqlalchemy/engine/default.py", line 552, in do_execute
cursor.execute(statement, parameters)
sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such table: user
[SQL: SELECT user.id AS user_id, user.username AS user_username, user.email AS user_email, user.password_hash AS user_password_hash, user.about_me AS user_about_me, user.last_seen AS user_last_seen
FROM user
WHERE user.username = ?
LIMIT ? OFFSET ?]
[parameters: ('john', 1, 0)]
(Background on this error at: http://sqlalche.me/e/e3q8)
这是因为单元测试实际上弄乱了sqlite数据库，并且我不得不以某种方式重新启动该数据库？或者，如果有人可以给我提示哪里可能出了问题，那将很棒。谢谢！