扭曲的井盖：如何在应用中访问服务器？

Question

我需要在运行时连接到我的twisted应用程序，我正在尝试让twisted.manhole为我工作。我的系统是Mac OSX 10.6，默认安装了twisted 8.2。

使用twistd的示例服务器可以正常工作。启动时会有关于md5、sha和twisted.protocols.telnet的弃用警告，但manhole服务器实际上能正常工作，我可以访问我应用程序的内部信息：

host:client user$ telnet localhost 4040
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.

twisted.manhole.telnet.ShellFactory
Twisted 8.2.0
username: admin
password: *****
>>> dir()
['_', '__builtins__', 'factory', 'service']
>>> factory
<twisted.manhole.telnet.ShellFactory instance at 0x101256440>
>>> service
<twisted.application.internet.TCPServer instance at 0x10124ff38>
>>> service.parent
<twisted.application.service.MultiService instance at 0x1014b0cf8>
>>> 

现在我尝试将这个集成到我的应用程序中：

# test_manhole.tac

from twisted.application.internet import TCPServer
from twisted.application.service  import Application, IServiceCollection
from twisted.manhole.telnet       import ShellFactory

shell_factory = ShellFactory()
shell_factory.username = 'admin'
shell_factory.password = 'admin'
shell_factory.namespace['some_value'] = 42
shell_tcp_server = TCPServer(4040, shell_factory)

application = Application('test')
serviceCollection = IServiceCollection(application)

shell_tcp_server.setServiceParent(serviceCollection)

在一个终端中运行上面的代码：

host:server user$ twistd -noy test_manhole.tac
(omitting the same DeprecationWarnings about md5, sha and twisted.protocols.telnet as earlier)
2011-08-24 16:52:13+1000 [-] Log opened.
2011-08-24 16:52:13+1000 [-] twistd 8.2.0 (/usr/bin/python2.6 2.6.1) starting up.
2011-08-24 16:52:13+1000 [-] reactor class: twisted.internet.selectreactor.SelectReactor.
2011-08-24 16:52:13+1000 [-] twisted.manhole.telnet.ShellFactory starting on 4040
2011-08-24 16:52:13+1000 [-] Starting factory <twisted.manhole.telnet.ShellFactory instance at 0x1012cfdd0>
2011-08-24 16:52:13+1000 [-] start service:  <twisted.application.internet.TCPServer instance at 0x1012cff80>

在第二个终端中，运行一个telnet客户端：

host:client user$ telnet localhost 4040
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.

twisted.manhole.telnet.ShellFactory
Twisted 8.2.0
username: admin
password: *****
>>> dir()
['_', '__builtins__', 'factory', 'service', 'some_value']
>>> factory
<twisted.manhole.telnet.ShellFactory instance at 0x1012cfdd0>
>>> service
>>> service == None
True
>>> service.parent
      ...
exceptions.AttributeError: 'NoneType' object has no attribute 'parent'
>>> some_value
42

看起来这个服务对象无法用来访问应用程序的内部信息。

好的，因为twisted.protocols.telnet似乎已经被twisted.conch.telnet取代，所以我尝试使用更新的模块：

# test_manhole_2.tac

from twisted.application.service import Application, IServiceCollection
from twisted.conch.manhole_tap   import makeService

options = \
{
    # for some reason, these must
    # all exist, even if None
    'namespace'  : None,
    'passwd'     : 'users.txt',
    'sshPort'    : None,
    'telnetPort' : '4040',
}

shell_service = makeService(options)

application = Application('test')
serviceCollection = IServiceCollection(application)

shell_service.setServiceParent(serviceCollection)

“密码文件”users.txt可以只包含一行示例用户名和密码，比如admin:admin。

启动测试服务器：

host:server user$ twistd -noy test_manhole_2.tac
(omitting DeprecationWarnings about md5 and sha)
2011-08-24 17:44:26+1000 [-] Log opened.
2011-08-24 17:44:26+1000 [-] twistd 8.2.0 (/usr/bin/python2.6 2.6.1) starting up.
2011-08-24 17:44:26+1000 [-] reactor class: twisted.internet.selectreactor.SelectReactor.
2011-08-24 17:44:26+1000 [-] twisted.internet.protocol.ServerFactory starting on 4040
2011-08-24 17:44:26+1000 [-] Starting factory <twisted.internet.protocol.ServerFactory instance at 0x10181e710>
2011-08-24 17:44:26+1000 [-] start service:  <twisted.application.service.MultiService instance at 0x1012553b0>
2011-08-24 17:44:26+1000 [-] start service:  <twisted.application.internet.TCPServer instance at 0x10181e998>

在第二个终端中，运行一个telnet客户端——注意，有些内容实际上是猜测，因为有问题的Mac OSX readline（或者其他什么原因）似乎吞掉了一些终端输出：

host:client user$ telnet localhost 4040
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Username: admin
Password: *****

>>> dir()
['__builtins__']

所以现在看起来我从一个无用的service对象变成了根本没有对象。

twisted.manhole应该怎么正确使用呢？

Answer 1

继续使用 twisted.conch，然后在命名空间字典里放一些东西。

namespace = {"your_application_object": some_object}

options = {
    # for some reason, these must
    # all exist, even if None
    'namespace'  : namespace,
    'passwd'     : 'users.txt',
    'sshPort'    : None,
    'telnetPort' : '4040',
}