I am trying to perform a simple callback sequence in twisted. The idea is that I login to a service, and when the login has succeeded, I start sending commands. This is my code:
from twisted.internet import reactor, defer
class MyService:
def __init__ (self):
self.handle = None
def login(self):
def onConnect(handle):
self.handle = handle
return
df = defer.Deferred().addCallback(onConnect)
reactor.callLater(2, df.callback, "dummyhandle")
return df
def sendCommand(self, command):
def onResult(result):
print result
return result
if self.handle == None:
print "Not logged in"
return
else:
df = defer.Deferred().addCallback(onResult, result ="xxx")
return df
my = MyService ()
my.login().addCallback(my.sendCommand, command = "format")
reactor.run()
Running that code produces the following stacktrace:
Unhandled error in Deferred: Traceback (most recent call last): File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1179, in mainLoop
self.runUntilCurrent() File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 778, in runUntilCurrent
call.func(*call.args, **call.kw) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 280, in callback
self._startRunCallbacks(result) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 354, in _startRunCallbacks
self._runCallbacks()
--- <exception caught here> --- File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 371, in _runCallbacks
self.result = callback(self.result, *args, **kw) exceptions.TypeError: sendCommand() got multiple values for keyword argument 'command'
The important thing here is that sendCommand does not need the result of the login, but different data. It needs that login has completed (that is why I want it in the callback chain), but it is not interested on the result of the login (as long as it is not an error, which will be handled in the error chain anyway).
What am I doing wrong here?
Easy, the handler must have result as its first argument:
def sendCommand(self, in_result, command):
do_the_stuff
Related
I am trying to set up a web-app in Python using Flask, having multiple rooms for different users, however using join_room provided by Flask-SocketIO and executing the script this error is returned:
Exception in thread Thread-10:
Traceback (most recent call last):
File "D:\Python\Python39\lib\threading.py", line 954, in _bootstrap_inner
self.run()
File "D:\Python\Python39\lib\threading.py", line 892, in run
self._target(*self._args, **self._kwargs)
File "D:\Python\Python39\lib\site-packages\socketio\server.py", line 688, in _handle_event_internal
r = server._trigger_event(data[0], namespace, sid, *data[1:])
File "D:\Python\Python39\lib\site-packages\socketio\server.py", line 712, in _trigger_event
return self.handlers[namespace][event](*args)
File "D:\Python\Python39\lib\site-packages\flask_socketio\__init__.py", line 283, in _handler
return self._handle_event(handler, message, namespace, sid,
File "D:\Python\Python39\lib\site-packages\flask_socketio\__init__.py", line 751, in _handle_event
ret = handler(*args)
File "D:\master-thesis\safety-detector\server.py", line 30, in join_room
join_room(roomId)
File "D:\master-thesis\safety-detector\server.py", line 28, in join_room
roomId = data['roomId']
TypeError: string indices must be integers
If I comment out join_room(roomId) the assignment for camId works as expected, so I don't know why this error happens.
Backend code:
#socketio.on('connect')
def connection():
#socketio.on('join-room')
def join_room(data):
roomId = data['roomId']
camId = data['camId']
join_room(roomId)
emit('cam-connected', {'camId': camId}, broadcast=True)
#socketio.on('disconnect')
def on_disconnect():
leave_room(roomId)
emit('cam-disconnected', {'camId': camId}, broadcast=True)
You have a function named join_room() in your code, which is shadowing the join_room() function from Flask-SocketIO.
You also have a very strange structure for your Socket.IO handlers with inner functions that is not likely to work (or maybe the indentation got messed up when you copy/pasted the code in your question?). Try something like this:
#socketio.on('connect')
def connection():
pass
#socketio.on('join-room')
def my_join_room(data): # <--- rename this to something other than join_room
roomId = data['roomId']
camId = data['camId']
join_room(roomId)
emit('cam-connected', {'camId': camId}, broadcast=True)
#socketio.on('disconnect')
def on_disconnect():
leave_room(roomId)
emit('cam-disconnected', {'camId': camId}, broadcast=True)
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.
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.
I'm working on an application in which a server and client are being created; the ServerAPI is using SimpleXMLRPCServer and the ClientAPI is using xmlrpclib. The client is initiated with:
class w_Client:
def __init__(self, ServerIP, ServerPort, ClientIP):
self.conn = xmlrpclib.ServerProxy("http://" + ServerIP + ":" + str(ServerPort))
self.ClientIP = ClientIP
upon a button being pressed in the application, an xml specification file is created and passed thru
def Create(self, XMLstring):
return self.conn.Create(XMLstring, self.ClientIP)
I've already checked to make sure that the XMLstring is valid XML; however, when I get press the button, I get the following error:
Traceback (most recent call last):
File "/home/app/UI/MainWindow.py", line 461, in compile
xmlFile = compiler.compile()
File "/home/app/Core/Compiler.py", line 75, in compile
self.compile_top()
File "/home/app/Core/Compiler.py", line 354, in compile_top
status = mainWidgets["w_client"].Create(xmlString)
File "/home/app/Wireless/ClientAPI.py", line 12, in Create
return self.conn.Create(XMLstring, self.ClientIP)
File "/usr/lib/python2.7/xmlrpclib.py", line 1233, in __call__
return self.__send(self.__name, args)
File "/usr/lib/python2.7/xmlrpclib.py", line 1591, in __request
verbose=self.__verbose
File "/usr/lib/python2.7/xmlrpclib.py", line 1273, in request
return self.single_request(host, handler, request_body, verbose)
File "/usr/lib/python2.7/xmlrpclib.py", line 1306, in single_request
return self.parse_response(response)
File "/usr/lib/python2.7/xmlrpclib.py", line 1482, in parse_response
return u.close()
File "/usr/lib/python2.7/xmlrpclib.py", line 794, in close
raise Fault(**self._stack[0])
xmlrpclib.Fault: <Fault 1: "<type 'exceptions.TypeError'>:'NoneType' object has no attribute '__getitem__'">
I've also made sure that the ClientIP is passed correctly. Otherwise, I'm not entirely sure what's going on or how to even go about fixing it.
<type 'exceptions.TypeError'>:'NoneType' object has no attribute '__getitem__'
This exception may have been generated by the xmlrpc method you were calling (i.e. server side).
I suggest that you add verbose=True to your instantiation of the server proxy:
xmlrpclib.ServerProxy("http://" + ServerIP + ":" + str(ServerPort),verbose=True)
This will allow you to see what you're sending and receiving.
It seems the method you're calling is expecting a dict
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.