I have a XMLRPC server running:
#!/usr/bin/env python
from SimpleXMLRPCServer import SimpleXMLRPCServer
import subprocess
import os
def testls():
retcode=subprocess.call(["ls", "/etc"])
return retcode
server = SimpleXMLRPCServer(('192.168.15.20',8888),logRequests=True)
server.register_function(testls)
server.register_introspection_functions()
try:
server.serve_forever()
finally:
server.server_close()
I need to be able to call it from a ruby client. From what I have found. it seems that it should be this:
require xmlrpc/client
server = XMLRPC::Client.new2("http://192.168.15.20:8888/")
But it returns the following, which suggests that it is not able to reach the service.
=> #<XMLRPC::Client:0x2ab0f5caacf8 #parser=nil, #timeout=30, #path="/", #password=nil, #http_header_extra=nil, #use_ssl=false, #host="192.168.15.20", #user=nil, #proxy_port=nil, #auth=nil, #cookie=nil, #create=nil, #port=8888, #http=#<Net::HTTP 192.168.15.20:8888 open=false>, #proxy_host=nil, #http_last_response=nil>
I had better success with the following, but I was not able to invoke the method:
irb(main):069:0> server = XMLRPC::Client::Proxy.new("http://192.168.15.20","8888")
=> #<XMLRPC::Client::Proxy:0x2ab0f5c4ef48 #args=[], #server="http://192.168.15.20", #meth=:call, #prefix="8888.">
irb(main):070:0> s = server.call('system.listMethods')
NoMethodError: undefined method `call' for "http://192.168.15.20":String
from /usr/lib/ruby/1.8/xmlrpc/client.rb:608:in `send'
from /usr/lib/ruby/1.8/xmlrpc/client.rb:608:in `method_missing'
from (irb):70
from :0
What is the appropriate code to invoke a call from Ruby to a Python XML-RPC Server?
I know this is a rather old question, but since it doesn't have a selected answer, I thought I'd share my insights:
In ruby, the class XMLRPC::Client represents a lower level interface to the server:
server = XMLRPC::Client.new( "192.168.15.20", 8888 )
server.call 'system.listMethods'
The class XMLRPC::Client::Proxy is a higher level interface to (parts of) the server that allows for a more natural server method invocation:
system = server.proxy('system')
system.listMethods
Similarly, to access the server's 'root' methods (like those registered via register_function in Python):
main = server.proxy
main.testls
I'm not familiar with xmlrpc in Ruby, but I think you have to pass an XMLRPC::Client Object to XMLRPC::Client::Proxy.
Try stuff like this:
client = XMLRPC::Client.new( "http://192.168.15.20", 8888 )
server = XMLRPC::Client::Proxy.new( client, 8888 )
server.call "system.listMethods"
Maybe it works this way.
Related
I'm using following command to connect to weblgic using WLST,
java weblogic.wlst core.py
inside core.py I'm calling following command to connect to the weblogic admin. but some times the service url becomes unresponsive And my script hangs occasionally due to this. Is there any way to give a timeout to this connect() method or any other method to implement a timeout functionality?. Appreciate if someone can shed some light on this. Thanks.
connect(username,password,t3://:)
in earlier WebLogic versions they have provided following functionality(to ping), but they have removed it after 12.2*
java weblogic.Admin -url t3://localhost:7001 -username weblogic -password weblog
ic ping 3 100
This is a very common situation, where you can use Python's socket module to check that the Admin port is opened or not with the following function.
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
AdminIP = '192.168.33.10'
result = sock.connect_ex((AdminIP,7001))
if result == 0:
print "AdminPort is open you can connect"
else:
print "Admin Port is not yet open"
sock.close()
add your logic accordingly, HTH!
I'm a little over my head when it comes to this SSH thing. Basically I am trying to access a friends server through and SSH tunnel using twisted conch. He has given me the following information:
MONGO_HOST = "ip address"
MONGO_DB = "server name"
MONGO_USER = "user name"
MONGO_PASS = "server password"
I was able to get this information to work using the python library motor.motor_asyncio (I need this be async compatible in order to use with other libraries) but for reasons that I can get into if necessary, will not work on the raspberry pi that I plan on running this program on.
Long story short, I was wondering if anyone could help me with some sample code to access my friends server using the information given above with twisted.conch.
I looked on the twisted.conch readthedocs, but the example needs more information than I can provide (I think) and is WAY over my head in terms of networking/SSH/etc.
Thanks in advance. I am willing to put in the work, but I need to know where to look.
Here is my relevant bit of code so far:
from motor.motor_asyncio import AsyncIOMotorClient
from sshtunnel import SSHTunnelForwarder
MONGO_HOST = "host address"
MONGO_DB = "server name"
MONGO_USER = "username"
MONGO_PASS = "password"
server = SSHTunnelForwarder(
MONGO_HOST,
ssh_username=MONGO_USER,
ssh_password=MONGO_PASS,
remote_bind_address=('address', gate),
local_bind_address=('address', gate)
)
server.start()
client = AsyncIOMotorClient('address', gate)
db = client.server_name
You can forward ports with Conch like this:
rom twisted.internet.defer import Deferred
from twisted.conch.scripts import conch
from twisted.conch.scripts.conch import ClientOptions, SSHConnection
from twisted.conch.client.direct import connect
from twisted.conch.client.default import SSHUserAuthClient, verifyHostKey
from twisted.internet.task import react
def main(reactor):
# authenticate as this user to SSH
user = "sshusername"
# the SSH server address
host = "127.0.0.1"
# the SSH server port number
port = 22
# a local port number to listen on and forward
localListenPort = 12345
# an address to forward to from the remote system
remoteForwardHost = "127.0.0.1"
# and the port number to forward to
remoteForwardPort = 22
conch.options = ClientOptions()
conch.options.parseOptions([
# don't ask the server for a shell
"--noshell",
# set up the local port forward
"--localforward={}:{}:{}".format(
localListenPort,
remoteForwardHost,
remoteForwardPort,
),
# specify the hostname for host key checking
host,
])
# don't stop when the last forwarded connection stops
conch.stopConnection = lambda: None
# do normal-ish authentication - agent, keys, passwords
userAuthObj = SSHUserAuthClient(user, conch.options, SSHConnection())
# create a Deferred that will tell `react` when to stop the reactor
runningIndefinitely = Deferred()
# establish the connection
connecting = connect(
host,
port,
conch.options,
verifyHostKey,
userAuthObj,
)
# only forward errors so the reactor will run forever unless the
# connection attempt fails. note this does not set up reconnection for a
# connection that succeeds and then fails later.
connecting.addErrback(runningIndefinitely.errback)
return runningIndefinitely
# run the reactor, call the main function with it, passing no other args
react(main, [])
Some of the APIs are weird because they are CLI focused. You don't have to do it this way but port forwarding is most easily accessible with these APIs rather than the APIs that are more focused on programmatic use.
As some of you may have seen recently I was struggling to get a simple Client/Server TCP connection up and running, where I could switch to TLS on issue of a command, as per the Twisted example at https://twistedmatrix.com/documents/14.0.0/core/howto/ssl.html#starttls-server, but modified to use certificate authentication. Well, the good news is that now works! Thanks to #Jean-PaulCalderone and #Glyph for their help.
However I now want to extend / transform my server side code into an ESMTP server - ie, let the client connect, server then advertises STARTTLS as part of its EHLO response, and if the client then responds with STARTTLS, negotiate and switch to a secure connection. I believe I need to modify the "TLSServer" class in my server code below to be inherited from twisted.mail.smtp.ESMTP instead of twisted.protocols.basic.LineReceiver - but not 100% sure here. Moreover, the API docs for t.m.s.ESMTP as found at http://twistedmatrix.com/documents/12.1.0/api/twisted.mail.smtp.ESMTP.html are a little thin on the ground (lots of undocumented methods).
Can anyone a) tell me if I am right regarding modifing the inheritance of my existing server code, and b) offer up some explanation of methods such as do_EHLO and ext_STARTTLS?
Ultimately I am looking for an SMTP server that will accept (secured) client connections, receive a mail from the client, and dump the mail to file.
My existing server code:
from twisted.internet import ssl, protocol, defer, task, endpoints
from twisted.protocols.basic import LineReceiver
from twisted.python.modules import getModule
from OpenSSL.crypto import load_privatekey, load_certificate, FILETYPE_PEM
class TLSServer(LineReceiver):
def lineReceived(self, line):
print("received: " + line)
if line == "STARTTLS":
print("-- Switching to TLS")
self.sendLine('READY')
self.transport.startTLS(self.factory.options)
def main(reactor):
caCertFile = open("/some/path/to/cacert.pem","r")
certFile = open("/some/path/to/server.crt","r")
keyFile = open("/some/path/to/server.key","r")
caCertData = caCertFile.read()
pKeyData = keyFile.read()
certData = certFile.read()
caCert = ssl.Certificate.loadPEM(caCertData)
cert = load_certificate(FILETYPE_PEM, certData)
pKey = load_privatekey(FILETYPE_PEM, pKeyData)
factory = protocol.Factory.forProtocol(TLSServer)
factory.options = ssl.CertificateOptions(privateKey=pKey, certificate=cert, trustRoot=caCert)
endpoint = endpoints.TCP4ServerEndpoint(reactor, 8000)
endpoint.listen(factory)
return defer.Deferred()
if __name__ == '__main__':
import starttls_server
task.react(starttls_server.main)
Thanks in advance!
You should not have your own TLSServer class. Instead, just use ESMTP directly as your server class. You've already identified the ext_STARTTLS method as interesting - basically, it already implements the logic that your TLSServer has in its lineReceived method.
Rather than doing factory.options = ..., you will want to pass ESMTP a contextFactory argument upon construction. At the simplest, you could do something like this:
sslCtxFactory = ssl.CertificateOptions(...)
factory = Factory.forProtocol(lambda: ESMTP(contextFactory=sslCtxFactory))
I believe that ESMTP advertises STARTTLS as an extension by default - at least, that's what a quick reading of the implementation of ESMTP.extensions() method says to me.
This question already has answers here:
Python: Binding Socket: "Address already in use"
(13 answers)
Closed 8 years ago.
I have a twisted python server which runs on port 8080, and i have written different API's which runs on this server. so i want all these API's to run on a single port no. but when i try to use same port all API's for ex : 8081 and run at the same time using python interpreter. at that time i am getting this error : twisted.internet.error.CannotListenError: Couldn't listen on any:8081: [Errno 98] Address already in use.
As i am new to twisted so don't know much of the things and there is no proper documentation on twisted . please someone guide me to solve this error :
Here is the Code snippets :
from twisted.internet import epollreactor
epollreactor.install()
from zope.interface import implements
from twisted.internet import reactor,interfaces
from functools import partial
from pymongo import Connection
import json
from bson.objectid import ObjectId
import server_1
import replacePlus_Space
global data, data_new, datadB, coll_auth, coll_person
class Login_user(server_1.HTTPEchoFactory):
def __init__(self):
server_1.HTTPEchoFactory.__init__(self,"testsite")
server_1.HTTPEchoFactory.initResources(self)
self.initResources()
def initResources(self):
print "in Login"
self.responses["/login_user"] = partial(self.user_login)
# To connect to DB and Check error cases and insert into mongoDB..!!!
def user_login(self, client):
# some functinality..!!!!
d = Login_user()
reactor.listenTCP(8081,d)
reactor.run()
Second code snippet is :
from twisted.internet import epollreactor
epollreactor.install()
from zope.interface import implements
from twisted.internet import reactor,interfaces
from functools import partial
from pymongo import Connection
import json
from bson.objectid import ObjectId
import server_1
import replacePlus_Space
class AddFriendDB(server_1.HTTPEchoFactory):
def __init__(self):
server_1.HTTPEchoFactory.__init__(self,"testsite")
server_1.HTTPEchoFactory.initResources(self)
self.initResources()
def initResources(self):
print "in add friend"
self.responses["/addFriend_DB"] = partial(self.addFriendDB)
# To connect to DB and Check error cases and insert into mongoDB..!!!
def addFriendDB(self, client):
#some functionality here..!!!
d = AddFriendDB()
reactor.listenTCP(8081,d)
reactor.run()
Translating the question
Many of the specifics in your question don't make sense, so I'm translating your question into:
I have a twisted python standalone program which runs on port 8080, and i have written a different standalone program which runs on this server. I want both programs to run on a single port no. When i try to use same port for all programs ex : using port 8081 for both programs. I am getting this error :twisted.internet.error.CannotListenError: Couldn't listen on any:8081: [Errno 98] Address already in use. As i am new to twisted i don't know much of the things and there is no proper documentation on twisted. please someone guide me to solve this error.
Twisted has great documentation
You commented that:
[...] there is no proper documentation on twisted
That statement is blatantly false.
Twisted certainly has proper documentation, and as compared to most frameworks it has excellent documentation. To name just a few of the many high quality documentation sources:
Dave Peticola's (krondo) Twisted Introduction - an excellent and deep introduction to twisted that begins by explaining the technology Twisted is built upon. If you really want to understand twisted, this (long) introduction is the place to start
The high quality and extensive documentation on on Twisted's primary website twistedmatrix.com
The source itself. Twisted has well commented and surprisingly understand source, if the above documentation doesn't teach you what you need figure it out from the code.
What causes "Address already in use"
As previously answered by Bart Friederichs:
Only one process can listen on a certain port. If you start process 1 to listen on port 8081, and then start another process on that same port, you get this error.
It is an error from the TCP stack, not from python or twisted.
This is a fundament truth of TCP/IP stacks across all operating systems (or at least all process based operating systems that could run Python).
The error is your operating system reminding you that when data comes to a IP port the OS/IP-stack was designed to only forward to one process, a process that is implementing an application level protocol on that port. The error happens when a second program attempts to re-register a port some other program has already registered.
Work-arounds in general
Upon running into a port reuse issue like this you have to ask yourself:
Are the two programs even running the same application-level protocol?
If they are the same protocol, does the protocol have routing such that for any given transaction the correct sub-program/routine be identified?
Are the two programs at a different location in the routing?
If they aren't the same protocol (I.E. one was HTTP and the other is FTP) or they are the same protocol but its a protocol that doesn't have routing (I.E. two instances of NTP) then there is no easy way to mix them because your trying to break the laws of IP (and the way that application protocol implementations are built). The only solution will be to encapsulate one (or both) of the protocol(s) into a common protocol that also has application-level routing (I.E. encapsulating FTP inside of HTTP and using the URI to route)
If they are the same protocol, and the protocol provides for a per-transaction routing (I.E. the URI inside of HTTP transactions) and they aren't at the same routing location, then there are easier solutions, namely:
Merge the two application into one.
If they are the same routable protocol but at a different location (I.E. HTTP protocol with the URI for the first program at /login and second program at /addfriend) it should be trivial to pull out the post-routing logic of the two programs/process and merge them into one program that does both functions
Front-end the programs with a redirector (This solution is only easy with HTTP because of the tools available).
If you have HTTP protocol programs that have routing to separate locations, but for some reason its hard to merge the logic together (I.E. one program is written in Java, the other in Python) then you can look at front-ending both programs with a redirector like nginx
The way you would use a redirector in a case like this is to run your two apps on two different unused ports (I.E. 12001, 12002), and then run the redirector on the port you want the service to be on, running it with a config file that will redirect to your two programs via their unique routing locations (via configs like SF: How to redirect requests to a different domain/url with nginx)
Code example
The following three programs illustrate the process of merging two programs into one, so both sets of logic can be accessed from the same port.
Two separate programs:
If you run the following code a web server will be started up on localhost:8081. If you then point your web browser at http://127.0.0.1:8081/blah the blah page will be displayed.
#!/usr/bin/python
from twisted.internet import defer, protocol, reactor # the reactor
from twisted.web.server import Site # make the webserver go
from twisted.web.resource import Resource
class BlahPage(Resource):
idLeaf = True
def render_GET(self, request):
return "<html><body>Blah Page!</body></html>"
class ShutdownPage(Resource):
def render_GET(self, request):
reactor.stop()
webroot = Resource()
webroot.putChild("blah", BlahPage())
webroot.putChild("shutdown", ShutdownPage())
def main():
# Register the webserver (TCP server) into twisted
webfactory = Site(webroot)
reactor.listenTCP(8081, webfactory)
print ("Starting server")
reactor.run()
if __name__ == '__main__':
main()
This code will start a web server on localhost:8082. If you then point your web browser at http://127.0.0.1:8082/foo the foo page will be displayed.
#!/usr/bin/python
from twisted.internet import defer, protocol, reactor # the reactor
from twisted.web.server import Site # make the webserver go
from twisted.web.resource import Resource
class FooPage(Resource):
idLeaf = True
def render_GET(self, request):
return "<html><body>Foo Page!</body></html>"
class ShutdownPage(Resource):
def render_GET(self, request):
reactor.stop()
webroot = Resource()
webroot.putChild("foo", FooPage())
webroot.putChild("shutdown", ShutdownPage())
def main():
# Register the webserver (TCP server) into twisted
webfactory = Site(webroot)
reactor.listenTCP(8082, webfactory)
print ("Starting server")
reactor.run()
if __name__ == '__main__':
main()
Merging the logic
This code is the merger of the two previous programs, as you can see it only required copying a small amount of code to glue both of the above into one that allows for access to http://127.0.0.1:8080/blah and http://127.0.0.1:8080/blah.
#!/usr/bin/python
from twisted.internet import defer, protocol, reactor # the reactor
from twisted.web.server import Site # make the webserver go
from twisted.web.resource import Resource
class BlahPage(Resource):
idLeaf = True
def render_GET(self, request):
return "<html><body>Blah Page!</body></html>"
class FooPage(Resource):
idLeaf = True
def render_GET(self, request):
return "<html><body>Foo Page!</body></html>"
class ShutdownPage(Resource):
def render_GET(self, request):
reactor.stop()
webroot = Resource()
webroot.putChild("foo", FooPage())
webroot.putChild("blah", BlahPage())
webroot.putChild("shutdown", ShutdownPage())
def main():
# Register the webserver (TCP server) into twisted
webfactory = Site(webroot)
reactor.listenTCP(8080, webfactory)
print ("Starting server")
reactor.run()
if __name__ == '__main__':
main()
Only one process can listen on a certain port. If you start process 1 to listen on port 8081, and then start another process on that same port, you get this error.
It is an error from the TCP stack, not from python or twisted.
Fix it either by choosing different ports for each process, or create a forking server.
I'm trying to build a DNS server in python. It must listen two ports (8007 - client, 8008 - admin). The client only send an URL and receives the respective IP. The admin has permissions to change the DNS table (add, remove,.. doesn't matter to this right now).
So my question is: how do I implement the server listening continuously on the two ports for any eventual request (we can have several clients at the same time but only one admin when he is operating)
my Server with one listening port:
from SocketServer import *
from threading import *
from string import *
import socket
class Server(ForkingMixIn, TCPServer): pass #fork for each client
class Handler(StreamRequestHandler):
def handle(self):
addr = self.request.getpeername()
print 'Got connection from', addr
data=(self.request.recv(1024)).strip()
if data not in dic: #dic -> dictionary with URL:IP
self.wfile.write('0.0.0.0')
else:
self.wfile.write(dic.get(data))
server = Server(('', 8007), Handler)
server.serve_forever()
No need to use threads.
Use twisted.
TwistedNames has support out of the box for a dns server. You can customize it as needed or read its source as base when you build yours.
You can use non-blocking sockets, and use the select call to read from the socket. This Sockets Programming HOWTO for Python article has a section on non-blocking sockets in Python that will help.
See also:
select (Python) | select (UNIX)
socket (Python) | socket (UNIX)