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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.

basehttpserver does not respond to other requests

When I open my local server on Android (192.168.1.4) and on pc at the same time, pc never shows page (it is loading and loading and loading...) - this error raises when I kill my server:
Exception happened during processing of request from ('192.168.1.4', 54734)
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 655, 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 310, in handle_one_request
self.raw_requestline = self.rfile.readline(65537)
File "/usr/lib/python2.7/socket.py", line 476, in readline
data = self._sock.recv(self._rbufsize)
KeyboardInterrupt
my server script:
# !/usr/bin/env python
# -*- coding: utf-8 -*-
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
PORT = 20000
class S(BaseHTTPRequestHandler):
def log_message(self, format, *args):
return
def _set_headers(self):
self.send_response(200)
self.send_header('Content-type', 'text/html')
self.send_header('Access-Control-Allow-Origin', '*')
self.end_headers()
def do_GET(self):
self._set_headers()
if self.path == "/other":
self.wfile.write("other")
if self.path == "/something":
self.wfile.write('something')
def do_HEAD(self):
self._set_headers()
def do_POST(self):
self._set_headers()
self.wfile.write("hello post")
def run(server_class=HTTPServer, handler_class=S, port=PORT):
server_address = ('', port)
httpd = server_class(server_address, handler_class)
httpd.serve_forever()
if __name__ == "__main__":
from sys import argv
if len(argv) == 2:
run(port=int(argv[1]))
else:
run()
What is wrong with my code please?

I think your server works well: like any server, it runs indefinitely.
To see it working, just point your browser on the following URL: http://localhost:20000/something or http://127.0.0.1:20000/something.
You should get the text "something".
You should consider using Flask.

No idea, if this is correct approach but setting timeout helped:
...
def log_message(self, format, *args):
return
def setup(self):
BaseHTTPRequestHandler.setup(self)
self.request.settimeout(0.5)
...

https://pymotw.com/2/BaseHTTPServer/#threading-and-forking says:
HTTPServer is a simple subclass of SocketServer.TCPServer, and does not use multiple threads or processes to handle requests. To add threading or forking, create a new class using the appropriate mix-in from SocketServer.

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.

HTTP server hangs while accepting packets

I have written a simple http server to handle POST requests:
class MyHandler( BaseHTTPServer.BaseHTTPRequestHandler):
def do_POST( self ):
ctype, pdict = cgi.parse_header(self.headers.getheader('content-type'))
postvars = {}
try:
if ctype == 'application/x-www-form-urlencoded':
length = int(self.headers.getheader('content-length'))
postvars = cgi.parse_qs(self.rfile.read(length), keep_blank_values=1)
self.send_response( 200 )
self.send_header( "Content-type", "text")
self.send_header( "Content-length", str(len(body)) )
self.end_headers()
self.wfile.write(body)
except:
print "Error"
def httpd(handler_class=MyHandler, server_address = ('2.3.4.5', 80)):
try:
print "Server started"
srvr = BaseHTTPServer.HTTPServer(server_address, handler_class)
srvr.serve_forever() # serve_forever
except KeyboardInterrupt:
server.socket.close()
if __name__ == "__main__":
httpd( )
The server runs fine but sometimes it just hangs. When I press CTRL+C it gives the following error and then continues receiving data:
Exception happened during processing of request from ('1.1.1.2', 50928)
Traceback (most recent call last):
File "/usr/lib/python2.6/SocketServer.py", line 281, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 307, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 320, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.6/SocketServer.py", line 615, in __init__
self.handle()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 329, in handle
self.handle_one_request()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 312, in handle_one_request
self.raw_requestline = self.rfile.readline()
File "/usr/lib/python2.6/socket.py", line 406, in readline
data = self._sock.recv(self._rbufsize)
KeyboardInterrupt
Can someone tell me how to correct this? I can't make sense of the errors.

I completely rewrote my solution in order to fix two disadvantages:
It can treat timeout even if client has opened only a connection but did not start communicate.
If the client opens a connection, a new server process is forked. A slow client can not block other.
It is based on your code as most as possible. It is now a complete independent demo. If you open a browser on http://localhost:8000/ and write 'simulate error' to form and press submit, it simulates runtime error.
from http.server import HTTPServer, BaseHTTPRequestHandler
from socketserver import ForkingMixIn
from urllib.parse import parse_qs
class MyHandler(BaseHTTPRequestHandler):
def do_POST(self):
ctype, pdict = self.headers.get_params(header='content-type')[0]
postvars = {}
try:
if ctype == 'application/x-www-form-urlencoded':
length = int(self.headers['content-length'])
postvars = parse_qs(self.rfile.read(length), keep_blank_values=1
encoding='utf-8')
assert postvars.get('foo', '') != ['bar'] # can simulate error
body = 'Something\n'.encode('ascii')
self.send_response(200)
self.send_header("Content-type", "text")
self.send_header("Content-length", str(len(body)))
self.end_headers()
self.wfile.write(body)
except Exception:
self.send_error(500)
raise
def do_GET(self):
# demo for testing POST by web browser - without valid html
body = ('Something\n<form method="post" action="http://%s:%d/">\n'
'<input name="foo" type="text"><input type="submit"></form>\n'
% self.server.server_address).encode('ascii')
self.send_response(200)
self.send_header("Content-type", "text/html")
self.send_header("Content-length", str(len(body)))
self.end_headers()
self.wfile.write(body)
class ForkingHTTPServer(ForkingMixIn, HTTPServer):
def finish_request(self, request, client_address):
request.settimeout(30)
# "super" can not be used because BaseServer is not created from object
HTTPServer.finish_request(self, request, client_address)
def httpd(handler_class=MyHandler, server_address=('localhost', 8000)):
try:
print("Server started")
srvr = ForkingHTTPServer(server_address, handler_class)
srvr.serve_forever() # serve_forever
except KeyboardInterrupt:
srvr.socket.close()
if __name__ == "__main__":
httpd()
Forking can be disabled for e.g. debugging purposes by removing class SocketServer.ForkingMixIn from code.
EDIT Updated for Python 3, but a warning from Python 3 docs should be noted:
Warning: http.server is not recommended for production. It only implements basic security checks.

Spawning multiple browsers from Selenium RC utilizing Python

I've been trying to develop an automated test case solution using Selenium RC and Python and after lengthy testing I've hit a pretty hard block in the road, so to speak.
I have three files: unit.py, case1.py, and case1m.py
unit.py configures instances of case1m.py with a browser and a port, then runs the test by sending the case1m instance through unittest.main().
The case1.py file is a vanilla case that is generated from Selenium IDE; when run from the command line, it executes the test case and exits with OK. I used this file to help debug the failing points of the other two files.
Here is the source for all three files:
unit.py:
import unittest
from case1m import case1m
browser = "*chrome"
port = 4444
a = case1m()
a.setBrowser("*chrome",4444)
unittest.main(a)
case1m.py - handles browser/port arguments and runs selenium test cases:
from selenium import selenium
import unittest, time, re
class case1m(unittest.TestCase):
def setBrowser(self,b,p):
print "entered setBrowser"
self.browser = b
self.port = p
print "leaving setBrowser"
self.setUp()
def setUp(self):
print self.browser,", ",self.port
self.verificationErrors = []
self.selenium = selenium("localhost", self.browser, self.port, "http://megagate-ffcdcb.xl_net.internal/")
self.selenium.start()
print "end setUp"
self.runTest()
def runTest(self):
print "entered runTest"
sel = self.selenium
sel.open("/seltest/")
try: self.failUnless(sel.is_text_present("BODY"))
except AssertionError, e: self.verificationErrors.append(str(e))
print "leaving runTest"
self.tearDown()
def tearDown(self):
print "entered tearDown"
self.selenium.stop()
self.assertEqual([], self.verificationErrors)
print "leaving tearDown"
case1.py:
from selenium import selenium
import unittest, time, re
class case1(unittest.TestCase):
def setUp(self):
print "entered setUp"
self.verificationErrors = []
self.selenium = selenium("localhost", 4444, "*chrome", "http://megagate-ffcdcb.xl_net.internal/")
self.selenium.start()
def runTest(self):
sel = self.selenium
sel.open("/seltest/")
try: self.failUnless(sel.is_text_present("BODY"))
except AssertionError, e: self.verificationErrors.append(str(e))
def tearDown(self):
self.selenium.stop()
self.assertEqual([], self.verificationErrors)
if __name__ == '__main__':
unittest.main()
The first problem I ran into was passing the browser and port values to an instance of the case1m class. I tried using __init__ to collect them as arguments, but apparently sub-classing the TestCase class and then adding an __init__ override causes problems; the setUp(), runTest() and tearDown() methods no longer triggered automatically as they do in the case1 class.
So instead, I overrode and inserted a setBrowser() method to collect the values and create the browser and port variables within the class instance. This again causes the same issue as before, so I resorted to inserting method calls into setUp(), runTest() and tearDown(). When executed, it runs until it tries the do_command() method in the selenium instance.
Here is the error:
Traceback (most recent call last):
File "C:\sel-test\unit.py", line 13, in
a.setBrowser("*chrome",4444)
File "C:\sel-test\case1m.py", line 10, in setBrowser
self.setUp()
File "C:\sel-test\case1m.py", line 16, in setUp
self.selenium.start()
File "C:\Python26\lib\selenium.py", line 190, in start
result = self.get_string("getNewBrowserSession", [self.browserStartCommand, self.browserURL, self.extensionJs])
File "C:\Python26\lib\selenium.py", line 225, in get_string
result = self.do_command(verb, args)
File "C:\Python26\lib\selenium.py", line 213, in do_command
conn.request("POST", "/selenium-server/driver/", body, headers)
File "C:\Python26\lib\httplib.py", line 910, in request
self._send_request(method, url, body, headers)
File "C:\Python26\lib\httplib.py", line 947, in _send_request
self.endheaders()
File "C:\Python26\lib\httplib.py", line 904, in endheaders
self._send_output()
File "C:\Python26\lib\httplib.py", line 776, in _send_output
self.send(msg)
File "C:\Python26\lib\httplib.py", line 735, in send
self.connect()
File "C:\Python26\lib\httplib.py", line 716, in connect
self.timeout)
File "C:\Python26\lib\socket.py", line 500, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
socket.gaierror: [Errno 10109] getaddrinfo failed
My questions is: why does the unit.py/case1m.py combination result in socket.gaierror when the case1.py file will run without error? From what I can see, the selenium class should be receiving the exact same information by the time it reaches self.do_command(). The only difference is that case1.py is being run directly from the commandline, while case1m.py is being run as an imported module.

Looking at the 2 code snippets side by side, I think you have inverted the browser and port arguments. This is probably the source of your error.
case1.py (runs fine):
self.selenium = selenium("localhost", 4444, "*chrome", "http://megagate-ffcdcb.xl_net.internal/")
case1m.py (socket error):
self.selenium = selenium("localhost", self.browser, self.port, "http://megagate-ffcdcb.xl_net.internal/")