我有一个python BaseHTTPServer，它通过.all（）查询返回一个餐馆列表。它在第一次运行时工作正常，但在更新后我得到了
Exception happened during processing of request from ('10.0.2.2', 49927)
Traceback (most recent call last):
File "/usr/lib/python2.7/SocketServer.py", line 295, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.7/SocketServer.py", line 321, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.7/SocketServer.py", line 334, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.7/SocketServer.py", line 649, in __init__
self.handle()
File "/usr/lib/python2.7/BaseHTTPServer.py", line 340, in handle
self.handle_one_request()
File "/usr/lib/python2.7/BaseHTTPServer.py", line 328, in handle_one_request
method()
File "webserver.py", line 43, in do_GET
allRestaurants = session.query(Restaurant).all()
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2703, in all
return list(self)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2855, in __iter__
return self._execute_and_instances(context)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2876, in _execute_and_instances
close_with_result=True)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2885, in _get_bind_args
**kw
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2867, in _connection_from_session
conn = self.session.connection(**kw)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 966, in connection
execution_options=execution_options)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 971, in _connection_for_bind
engine, execution_options)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 382, in _connection_for_bind
self._assert_active()
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 276, in _assert_active
% self._rollback_exception
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/exc.py", line 258, in __str__
details.append("[parameters: %r]" % params_repr)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/util.py", line 368, in __repr__
return self._repr_multi(self.params, typ)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/util.py", line 386, in _repr_multi
for params in multi_params)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/util.py", line 386, in <genexpr>
for params in multi_params)
File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/util.py", line 412, in _repr_params
", ".join(trunc(value) for value in params)
TypeError: 'int' object is not iterable
.all（）查询是否返回int而不是列表？ 或者这是一些内部错误，sqlalchemy的一部分传递另一部分int而不是可迭代的东西？ 它超出了我的专业知识来调试库，所以我只是摸不着头脑。 请帮忙。 这是我的网络服务器文件的缩写版本：
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
import cgi
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from database_setup import Base, Restaurant, MenuItem
# Database setup on webserver load instead of pageload
dbpath = 'sqlite:///restaurantmenu.db'
engine = create_engine(dbpath)
Base.metadata.bind = engine
DBSession = sessionmaker(bind = engine)
session = DBSession()
restaurants = session.query(Restaurant)
assert(type(restaurants) != "int")
class webServerHandler(BaseHTTPRequestHandler):
def do_GET(self):
try:
if self.path.endswith("/restaurants"):
self.send_response(200)
self.send_header('Content-type', 'text/html')
self.end_headers()
output = ""
output += "<html><body>"
assert(type(restaurants) != "int"), "type has changed."
session.flush()
allRestaurants = session.query(Restaurant).all()
for restaurant in allRestaurants:
output += "<h1>" + restaurant.name + "</h1>"
output += '''<a href="http://localhost:8080/restaurants/''' + repr(restaurant.id) + '''/edit">Edit</a>'''
output += '''<a href="http://localhost:8080/restaurants/''' + repr(restaurant.id) + '''/delete">Delete</a>'''
output += "</body></html>"
self.wfile.write(output)
print(output)
return
if self.path.endswith("/edit"):
self.send_response(200)
self.send_header('Content-type', 'text/html')
self.end_headers()
id = int(self.path.split('/')[-2])
restaurant = restaurants.filter_by(id = id).one()
output = ""
output += "<html><body>"
output += "<h1>" + restaurant.name + "</h1>"
output += '''<form method='POST' enctype='multipart/form-data' action='/restaurants/''' + repr(restaurant.id) + '''/edit'><h2>Please rename the restaurant</h2><input name="message" type="text" ><input type="submit" value="Submit"> </form>'''
output += "</body></html>"
self.wfile.write(output)
print(output)
return
except IOError:
self.send_error(404, 'File Not Found: %s' % self.path)
def do_POST(self):
try:
self.send_response(301)
self.send_header('Content-type', 'text/html')
self.end_headers()
ctype, pdict = cgi.parse_header(
self.headers.getheader('content-type'))
if ctype == 'multipart/form-data':
fields = cgi.parse_multipart(self.rfile, pdict)
formName = self.headers.getheader('name')
print(fields)
print(self.path)
messagecontent = fields.get('message')
id = int(self.path.split('/')[-2])
restaurant = restaurants.get(id)
restaurant.name = messagecontent
session.add(restaurant)
session.commit()
DBSession = sessionmaker(bind = engine)
session = DBSession()
assert (restaurants.filter_by(id = id).one().name == messagecontent), "Database update failure"
output = ""
output += "<html><body>"
output += " <h2> Restaurant renamed: </h2>"
output += "<h1> %s </h1>" % messagecontent[0]
output += '''<form method='POST' enctype='multipart/form-data' action='/hello'><h2>What would you like me to say?</h2><input name="message" type="text" ><input type="submit" value="Submit"> </form>'''
output += "</body></html>"
self.wfile.write(output)
print(output)
except:
pass
UPDATE - 我在数据库提交后添加了DBSession = sessionmaker（bind = engine）和session = DBSession（），现在有了一个InterfaceError：unprintable InterfaceError对象
答案 0 :(得分：0)
管理解决我遇到的多个问题！
重要的是，不要尝试为网络服务器创建一个会话实例，就像我在do_GET和do_POST方法之外声明会话变量一样。
这是因为文件加载创建了一个会话 - ＆gt;适用于第一个查询 - ＆gt;但是，do_POST方法会在commit()调用后使会话无效。这意味着在第二个查询中会话返回一个int（我假设这是一个错误代码形式sqlalchemy），因此是TypeError。
其次，POST方法返回一个表单字段值列表，然后我尝试将其分配给String数据库字段。