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int treated as `self' in python3

I want to build a simple server that dispatches requests depending on their path. So I wrote the following code:
from http.server import HTTPServer, BaseHTTPRequestHandler
import json
import socket
class Handler:
"""处理对应资源的请求"""
def __init__(self, dispatcher):
self.dispatcher = dispatcher
def handle(self):
"""根据dispatcher解析出来的path，调用对应的方法"""
command = 'do_' + self.dispatcher.command
print(command)
if not hasattr(self, command):
return;
method = getattr(self, command)
method(self)
def do_GET(self):
response = {
'message': 'message'
}
dispatcher.protocol_version = 'HTTP/1.1'
dispatcher.send_response(200, 'OK')
dispatcher.send_header('Content-type', 'text/plain')
dispatcher.wfile.write(bytes(json.dumps(response), 'utf-8'))
class dispatcher(BaseHTTPRequestHandler):
"""
根据url的不同分发请求
"""
def handle_one_request(self):
try:
self.raw_requestline = self.rfile.readline(65537)
if len(self.raw_requestline) > 65536:
self.requestline = ''
self.request_version = ''
self.command = ''
self.send_error(HTTPStatus.REQUEST_URI_TOO_LONG)
return
if not self.raw_requestline:
self.close_connection = True
return
if not self.parse_request():
# An error code has been sent, just exit
return
print(self.command)
print(self.path)
if self.path.startswith('/wrong'):
Handler(self).handle()
self.wfile.flush() #actually send the response if not already done.
except socket.timeout as e:
#a read or a write timed out. Discard this connection
self.log_error("Request timed out: %r", e)
self.close_connection = True
return
if __name__ == '__main__':
server = HTTPServer(('', 8080), dispatcher)
server.serve_forever()
The dispatcher will parse the incoming request and get the path so that it can decide which handler to call(though there is only one here for now).
In the handler class, it will call corresponding method based on the http method. In the do_GET method, it will call some methods in the dispatcher and that's where things go wrong.
When I ran this program and execute curl http://localhost:8080/wrong, I had the following exception:
GET
/wrong
do_GET
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 50072)
Traceback (most recent call last):
File "/usr/lib/python3.5/socketserver.py", line 313, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python3.5/socketserver.py", line 341, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python3.5/socketserver.py", line 354, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3.5/socketserver.py", line 681, in __init__
self.handle()
File "/usr/lib/python3.5/http/server.py", line 422, in handle
self.handle_one_request()
File "hello.py", line 51, in handle_one_request
Handler(self).handle()
File "hello.py", line 18, in handle
method()
File "hello.py", line 25, in do_GET
dispatcher.send_response(200, 'OK')
File "/usr/lib/python3.5/http/server.py", line 487, in send_response
self.log_request(code)
AttributeError: 'int' object has no attribute 'log_request'
----------------------------------------
log_request is defined as follows in the super class of dispatcher:
def log_request(self, code='-', size='-'):
# blablabla
and it is called in dispatcher.send_response.
I guess the problem is that the 200 is treated as self by the interpreter.
If my guess is right, why is this happening?
If not, what causes this exception?
I know this question is still in the grammar level, but I'd appreciate it if someone can help me.

builtins.TypeError: 'NoneType' object is not callable in Twisted

I encountered a TypeError when I used twisted to create a TCP server.
When I run the client.py after starting server.py, I receive the error presented below in the Error traceback section.
I have no idea about this error. However, I am sure the error happens at server.py.
server.py:
from twisted.internet import protocol, reactor
from time import ctime
PORT = 1234
class TserverProtocols(protocol.Protocol):
def connectionMade(self):
clnt = self.clnt = self.transport.getPeer().host
print('...connected from:', clnt)
def dataReceived(self, data):
self.transport.write(('[%s] %s' %(ctime(),data)).encode())
factory = protocol.Factory()
factory.protocols = TserverProtocols
print('waiting for connetion...')
reactor.listenTCP(PORT, factory)
reactor.run()
client.py:
from twisted.internet import protocol, reactor
HOST = 'localhost'
PORT = 1234
class TSClntProtocol(protocol.Protocol):
def sendData(self):
data = input('>')
if data:
print('...sending %s' % data)
self.transport.write(data.encode())
else:
self.transport.loseConnetion()
def connectionMade(self):
self.sendData()
def dataReceived(self, data):
print(data)
self.sendData()
class TSCFactorty(protocol.ClientFactory):
protocol = TSClntProtocol
clientConnetionLost = clientConnectionFailed = lambda slef, connector, reason:reactor.stop()
reactor.connectTCP(HOST, PORT, TSCFactorty())
reactor.run()
Error traceback:
Unhandled Error
Traceback (most recent call last):
File "/usr/local/lib/python3.5/dist-packages/twisted/python/log.py", line 86, in callWithContext
return context.call({ILogContext: newCtx}, func, *args, **kw)
File "/usr/local/lib/python3.5/dist-packages/twisted/python/context.py", line 122, in callWithContext
return self.currentContext().callWithContext(ctx, func, *args, **kw)
File "/usr/local/lib/python3.5/dist-packages/twisted/python/context.py", line 85, in callWithContext
return func(*args,**kw)
File "/usr/local/lib/python3.5/dist-packages/twisted/internet/posixbase.py", line 597, in _doReadOrWrite
why = selectable.doRead()
--- <exception caught here> ---
File "/usr/local/lib/python3.5/dist-packages/twisted/internet/tcp.py", line 1069, in doRead
protocol = self.factory.buildProtocol(self._buildAddr(addr))
File "/usr/local/lib/python3.5/dist-packages/twisted/internet/protocol.py", line 133, in buildProtocol
p = self.protocol()
builtins.TypeError: 'NoneType' object is not callable

You have several typos in your code. Regarding your question, you should replace in server.py
factory.protocols = TserverProtocols
with
factory.protocol = TserverProtocols

How to mock stompest send, and connect methods

I am writing a log handler for ActiveMQ. I have one class, Messenger, to publish a message to ActiveMQ. Also, I added class Handler to handle this and get_logger to get this logger.
import json
import logging
from stompest.config import StompConfig
from stompest.sync import Stomp
class Messanger(object):
def __init__(self, uri):
self.cfg = StompConfig(uri)
def publish(self, queue, data):
data = json.dumps(data)
client = Stomp(self.cfg)
client.connect()
try:
client.send(queue, data)
except Exception, exc:
print "Error: ", exc
client.disconnect()
class Handler(logging.Handler):
def __init__(self, amq_uri, out_queue):
logging.Handler.__init__(self)
self.queue = queue
self.uri = uri
def emit(self, record):
msg = self.format(record)
messanger = Messanger(self.uri)
messanger.send(self.queue, msg)
def get_logger(uri, queue):
logger = logging.getLogger('testlogger')
logger.addHandler(Handler(uri, queue))
return logger
I have written a UT for this.
from unittest import TestCase
from mock import patch, Mock
from my_package import get_logger
class TestHandler(TestCase):
#patch('stompest.sync.client.Stomp')
def test_activemq_handler(self, mock_stomp):
URI = "tcp://localhost:61613"
QUEUE = "/queue/logger_queue"
mock_stomp.connect = Mock(return_value=1)
mock_stomp.send = Mock(return_value=2)
data = "This is test logging"
LOG = get_logger(URI, QUEUE)
LOG.error(data)
But still it goes to the original send method and tries to connect to the server.
Traceback (most recent call last):
File ".my_package/venv/lib/python2.7/site-packages/mock/mock.py", line 1305, in patched
return func(*args, **keywargs)
File "./my_package/tests/test_activemq_handler.py", line 23, in test_activemq_handler
LOG.error(data)
File "/System/Library/Python.framework/Versions/2.7/lib/python2.7/logging/__init__.py", line 1191, in error
self._log(ERROR, msg, args, **kwargs)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/logging/__init__.py", line 1284, in _log
self.handle(record)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/logging/__init__.py", line 1294, in handle
self.callHandlers(record)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/logging/__init__.py", line 1334, in callHandlers
hdlr.handle(record)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/logging/__init__.py", line 757, in handle
self.emit(record)
File "./my_package/__init__.py", line 28, in emit
messanger.send(self.queue, msg)
File "./my_package/clients/stomp_messanger.py", line 41, in send
client.connect()
File "./my_package/venv/lib/python2.7/site-packages/stompest/sync/client.py", line 85, in connect
for (broker, connectDelay) in self._failover:
File "./my_package/venv/lib/python2.7/site-packages/stompest/protocol/failover.py", line 48, in __iter__
yield broker, self._delay()
File "./my_package/venv/lib/python2.7/site-packages/stompest/protocol/failover.py", line 66, in _delay
raise StompConnectTimeout('Reconnect timeout: %d attempts' % self._maxReconnectAttempts)
StompConnectTimeout: Reconnect timeout: 0 attempts
How can I mock this?

The basic principle is that you patch where an object is looked up, which is not necessarily the same place as where it is defined.
You are adding the patch to the wrong place. The Messenger class module imports Stomp from stompest.sync before the tests run, and that's why your patching has no effect. You should patch the reference to Stomp in your module.
from unittest import TestCase
from mock import patch, Mock
from my_package import get_logger
class TestHandler(TestCase):
#patch('path.to.your.Messenger_class_module.Stomp') #path to your module
def test_activemq_handler(self, mock_stomp):
URI = "tcp://localhost:61613"
QUEUE = "/queue/logger_queue"
...
This will help if you need further clarification on why this is happening.

Unable to write into file using Twisted

I have this code snippet which I am using to establish a connection with a client and then writing all his text to a file. Here is the code
from twisted.internet.protocol import Protocol, Factory
from twisted.internet import reactor
import ctypes # An included library with Python install.
class DataTransfer(Protocol):
def connectionMade(self):
#self.transport.write("""connected""")
fwrite = open('/Applications/mamp/htdocs/datatest.txt','r+')
self.factory.clients.append(self)
print "clients are ", self.factory.clients
self.username = ""
self.password = ""
self.auth = False
self.ipaddress = self.transport.getPeer()
print self.ipaddress
def connectionLost(self, reason):
fwrite.close()
self.factory.clients.remove(self)
print reason
def dataReceived(self, data):
print data
fwrite.write(data)
a = data.split(':')
if len(a) > 1:
command = a[0]
content = a[1]
msg = ""
self.message(msg)
def message(self, message):
self.transport.write(message + '\n')
factory = Factory()
factory.protocol = DataTransfer
factory.clients = []
reactor.listenTCP(8889, factory)
print "Server started"
reactor.run()
I am executing this command pythonw socketListner.py. The server starts successfully. But when I connect to it using netcat command, I get the following in my terminal and the connection closes.
Unhandled Error
Traceback (most recent call last):
File "socketListner.py", line 42, in <module>
reactor.run()
File "/Library/Python/2.7/site-packages/twisted/internet/base.py", line 1194, in run
self.mainLoop()
File "/Library/Python/2.7/site-packages/twisted/internet/base.py", line 1206, in mainLoop
self.doIteration(t)
File "/Library/Python/2.7/site-packages/twisted/internet/selectreactor.py", line 143, in doSelect
_logrun(selectable, _drdw, selectable, method)
--- <exception caught here> ---
File "/Library/Python/2.7/site-packages/twisted/python/log.py", line 101, in callWithLogger
return callWithContext({"system": lp}, func, *args, **kw)
File "/Library/Python/2.7/site-packages/twisted/python/log.py", line 84, in callWithContext
return context.call({ILogContext: newCtx}, func, *args, **kw)
File "/Library/Python/2.7/site-packages/twisted/python/context.py", line 118, in callWithContext
return self.currentContext().callWithContext(ctx, func, *args, **kw)
File "/Library/Python/2.7/site-packages/twisted/python/context.py", line 81, in callWithContext
return func(*args,**kw)
File "/Library/Python/2.7/site-packages/twisted/internet/selectreactor.py", line 154, in _doReadOrWrite
self._disconnectSelectable(selectable, why, method=="doRead")
File "/Library/Python/2.7/site-packages/twisted/internet/posixbase.py", line 258, in _disconnectSelectable
selectable.connectionLost(failure.Failure(why))
File "/Library/Python/2.7/site-packages/twisted/internet/tcp.py", line 293, in connectionLost
protocol.connectionLost(reason)
File "socketListner.py", line 17, in connectionLost
fwrite.close()
exceptions.NameError: global name 'fwrite' is not defined

Your variable fwrite is defined locally in connectionMade. Try to make it an instance variable by defining it as self.fwrite everywhere you use it within your class.

Error when transport.write() from thread in twisted

I'm trying to make this simple server script where multiple clients connect to it and are stored in the factory.connected_clients dictionary. I then want to show a menu so the user executing the server can select what client does he want to work with and what commands does he want to send them (like in a reverse shell). Here's the code:
class RshServer(protocol.Protocol):
def __init__(self, factory, addr):
self.addr = addr
self.factory = factory
def connectionMade(self):
address = self.addr.host + ':' + str(self.addr.port)
self.factory.connected_clients[address] = self
print '[*] Connection made with ' + address
class RshFactory(Factory):
def __init__(self):
self.connected_clients = {}
def buildProtocol(self, addr):
return RshServer(self, addr)
def show_server_menu():
print '1. Show connected clients'
print '2. Open client interface'
msg = raw_input('Select an option: ')
return msg
def show_client_menu():
print '1. Show all processes'
msg = raw_input('Select an option: ')
return msg
def server_interface():
while 1:
msg = show_server_menu()
command = server_commands.get(msg, None)
if command: command()
def client_interface():
protocol_name = raw_input('Enter client address: ')
protoc = rsh_factory.connected_clients.get(protocol_name, None)
if protoc:
msg = show_client_menu()
protoc.transport.write(msg)
rsh_factory = RshFactory()
server_commands = {
'1' : lambda: sys.stdout.write(str(rsh_factory.connected_clients)+'\n'),
'2' : client_interface
}
reactor.listenTCP(8000, rsh_factory)
reactor.callInThread(server_interface)
reactor.run()
However, when I select a client and execute the client interface function I get this error:
Unhandled Error
Traceback (most recent call last):
File "rsh_twisted_serv.py", line 58, in <module>
reactor.run()
File "/usr/lib/python2.7/dist-packages/twisted/internet/base.py", line 1192, in run
self.mainLoop()
File "/usr/lib/python2.7/dist-packages/twisted/internet/base.py", line 1204, in mainLoop
self.doIteration(t)
File "/usr/lib/python2.7/dist-packages/twisted/internet/epollreactor.py", line 396, in doPoll
log.callWithLogger(selectable, _drdw, selectable, fd, event)
--- <exception caught here> ---
File "/usr/lib/python2.7/dist-packages/twisted/python/log.py", line 88, in callWithLogger
return callWithContext({"system": lp}, func, *args, **kw)
File "/usr/lib/python2.7/dist-packages/twisted/python/log.py", line 73, in callWithContext
return context.call({ILogContext: newCtx}, func, *args, **kw)
File "/usr/lib/python2.7/dist-packages/twisted/python/context.py", line 118, in callWithContext
return self.currentContext().callWithContext(ctx, func, *args, **kw)
File "/usr/lib/python2.7/dist-packages/twisted/python/context.py", line 81, in callWithContext
return func(*args,**kw)
File "/usr/lib/python2.7/dist-packages/twisted/internet/posixbase.py", line 627, in _doReadOrWrite
self._disconnectSelectable(selectable, why, inRead)
File "/usr/lib/python2.7/dist-packages/twisted/internet/posixbase.py", line 257, in _disconnectSelectable
selectable.readConnectionLost(f)
File "/usr/lib/python2.7/dist-packages/twisted/internet/tcp.py", line 279, in readConnectionLost
self.connectionLost(reason)
File "/usr/lib/python2.7/dist-packages/twisted/internet/tcp.py", line 293, in connectionLost
abstract.FileDescriptor.connectionLost(self, reason)
File "/usr/lib/python2.7/dist-packages/twisted/internet/abstract.py", line 207, in connectionLost
self.stopWriting()
File "/usr/lib/python2.7/dist-packages/twisted/internet/abstract.py", line 429, in stopWriting
self.reactor.removeWriter(self)
File "/usr/lib/python2.7/dist-packages/twisted/internet/epollreactor.py", line 344, in removeWriter
EPOLLOUT, EPOLLIN)
File "/usr/lib/python2.7/dist-packages/twisted/internet/epollreactor.py", line 321, in _remove
self._poller.unregister(fd)
exceptions.IOError: [Errno 2] No such file or directory
I believe this is error is due to the transport.write() being called from a non-reactor thread. Am I right? How should I solve this?
SOLUTION: as #Glyph stated, the problem was indeed that I was calling transport.write() from a non-reactor thread (more details in his answer). I used the solution he proposed by changing protoc.transport.write() to reactor.callFromThread(lambda: protoc.transport.write(msg))

I think you mean "called from a non-reactor thread". No code in Twisted is thread-safe unless explicitly specified. See the threading documentation for more information. Use reactor.callFromThread to invoke Twisted methods from your stdio-reading thread, or use StandardIO to tell Twisted to read from standard input instead.