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Can't initiate get request in web.py

I'm trying to run two servers using web.py and initiating calls from one to another. Both servers start normally but when I try to call a url the below stack trace is thrown.
import web
urls = (
'/ping', 'Ping',
'/acqlock/+(.*)', 'Acquire',
)
class MSA(web.application):
def run(self, port=8081, *middleware):
func = self.wsgifunc(*middleware)
return web.httpserver.runsimple(func, ('127.0.0.1', port))
app = MSA(urls, globals())
if __name__ == "__main__":
app.run(port=8081)
class Acquire:
def GET(self, resource_name):
print resource_name
response = app.request('http://127.0.0.1:8080/acqlock/' + resource_name, method='GET')
return response
But I keep getting this error after calling the /acqlock.
Traceback (most recent call last):
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 1245, in communicate
req.respond()
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 775, in respond
self.server.gateway(self).respond()
File "C:\Python27\lib\site-packages\web\wsgiserver\__init__.py", line 2018, in respond
response = self.req.server.wsgi_app(self.env, self.start_response)
File "C:\Python27\lib\site-packages\web\httpserver.py", line 306, in __call__
return self.app(environ, xstart_response)
File "C:\Python27\lib\site-packages\web\httpserver.py", line 274, in __call__
return self.app(environ, start_response)
File "C:\Python27\lib\site-packages\web\application.py", line 279, in wsgi
result = self.handle_with_processors()
File "C:\Python27\lib\site-packages\web\application.py", line 249, in handle_with_processors
return process(self.processors)
File "C:\Python27\lib\site-packages\web\application.py", line 246, in process
raise self.internalerror()
File "C:\Python27\lib\site-packages\web\application.py", line 515, in internalerror
parent = self.get_parent_app()
File "C:\Python27\lib\site-packages\web\application.py", line 500, in get_parent_app
if self in web.ctx.app_stack:
AttributeError: 'ThreadedDict' object has no attribute 'app_stack'

Use requests library for this.
import requests
response = requests.request(method='GET', url ='http://127.0.0.1:8080/acqlock/' + resource_name)
Note: You have used port 8080 in url even though you have hosted the web.py in 8081

Django server is hanging in request handler

I do a poll once a second, and after some idle time (10min - 1h) the server stops responding. If I press Ctrl-C handler is terminated and the server is back alive. Error after pressing Ctrl-C (while trying to connect with a new client):
...same messages repeat...
[22/Sep/2016 21:54:27] "GET /ajax/?id=STATUS_POLL&_=1474566714286 HTTP/1.1" 200 0
[2016-09-22 21:54:28,217: DEBUG/MainProcess] NONE
[22/Sep/2016 21:54:28] "GET /ajax/?id=STATUS_POLL&_=1474566714287 HTTP/1.1" 200 0
[2016-09-23 09:33:14,657: INFO/MainProcess] Starting view
[23/Sep/2016 09:36:34] "GET / HTTP/1.1" 200 18970
Traceback (most recent call last):
File "c:\python27\lib\wsgiref\handlers.py", line 86, in run
self.finish_response()
File "c:\python27\lib\wsgiref\handlers.py", line 128, in finish_response
self.write(data)
File "c:\python27\lib\wsgiref\handlers.py", line 212, in write
self.send_headers()
File "c:\python27\lib\wsgiref\handlers.py", line 270, in send_headers
self.send_preamble()
File "c:\python27\lib\wsgiref\handlers.py", line 194, in send_preamble
'Date: %s\r\n' % format_date_time(time.time())
File "c:\python27\lib\socket.py", line 328, in write
self.flush()
File "c:\python27\lib\socket.py", line 307, in flush
self._sock.sendall(view[write_offset:write_offset+buffer_size])
error: [Errno 10053] An established connection was aborted by the software in your host machine
[23/Sep/2016 09:36:34] "GET / HTTP/1.1" 500 59
Request handler:
class CTrackerView(TemplateView):
__process = ProcessWrapper()
#staticmethod
def ajax_handler(request):
if request.GET.get('id', "") == "STATUS_POLL":
if CTrackerView.__process.is_alive(no_log=False):
return HttpResponse("UPDATING")
else:
return HttpResponse("")
process_wrapper.py:
class ProcessWrapper:
def is_alive(self, no_log=False):
if (not hasattr(self, "_process")) or not self._process:
if not no_log:
log("NONE", DEBUG)
return False
As you can see from the last code fragment, it just checks the variable is not defined (process is deleted) and return False during all the idle time. (Message "NONE" in log). The problem is difficult to reproduce.

Error when serving html with WSGI

I am trying to make an application that serves a simple HTML form to the user and then calls a function when the user submits the form. It uses wsgiref.simple_server to serve the HTML. The server is encountering an error and I can't understand why. The code is as follows:
#!/usr/bin/python3
from wsgiref.simple_server import make_server
from wsgiref.util import setup_testing_defaults
import webbrowser # open user's web browser to url when server is run
from sys import exc_info
from traceback import format_tb
# Easily serves an html form at path_to_index with style at path_to_style
# Calls on_submit when the form is submitted, passing a dictionary with key
# value pairs { "input name" : submitted_value }
class SimpleServer:
def __init__(self, port=8000, on_submit=None, index_path="./index.html", css_path="./style.css"):
self.port = port
self.on_submit = on_submit
self.index_path = index_path
self.css_path = css_path
# Forwards request to proper method, or returns 404 page
def wsgi_app(self, environ, start_response):
urls = [
(r"^$", self.index),
(r"404$", self.error_404),
(r"style.css$", self.css)
]
path = environ.get("PATH_INFO", "").lstrip("/")
# Call another application if they called a path defined in urls
for regex, application in urls:
match = re.search(regex, path)
# if the match was found, return that page
if match:
environ["myapp.url_args"] = match.groups()
return application(environ, start_response)
return error_404(environ, start_response)
# Gives the user a form to submit all their input. If the form has been
# submitted, it sends the ouput of self.on_submit(user_input)
def index(self, environ, start_response):
# user_input is a dictionary, with keys from the names of the fields
user_input = parse_qs(environ['QUERY_STRING'])
# return either the form or the calculations
index_html = open(self.index_path).read()
body = index_html if user_input == {} else calculate(user_input)
mime_type = "text/html" if user_input == {} else "text/plain"
# return the body of the message
status = "200 OK"
headers = [ ("Content-Type", mime_type),
("Content-Length", str(len(body))) ]
start_response(status, headers)
return [body.encode("utf-8")]
def start_form(self):
httpd = make_server('', self.port, ExceptionMiddleware(self.wsgi_app))
url = "http://localhost:" + str(self.port)
print("Visit " + url)
# webbrowser.open(url)
httpd.serve_forever()
if __name__ == "__main__":
server = SimpleServer()
server.start_form()
When I run it, I get the error
127.0.0.1 - - [16/Dec/2014 21:15:57] "GET / HTTP/1.1" 500 0
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 138, in run
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 266, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
127.0.0.1 - - [16/Dec/2014 21:15:57] "GET / HTTP/1.1" 500 59
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 49354)
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 138, in run
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 266, in write
"write() argument must be a bytes instance"
AssertionError: write() argument must be a bytes instance
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.4/wsgiref/handlers.py", line 141, in run
self.handle_error()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 368, in handle_error
self.finish_response()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 180, in finish_response
self.write(data)
File "/usr/lib/python3.4/wsgiref/handlers.py", line 274, in write
self.send_headers()
File "/usr/lib/python3.4/wsgiref/handlers.py", line 331, in send_headers
if not self.origin_server or self.client_is_modern():
File "/usr/lib/python3.4/wsgiref/handlers.py", line 344, in client_is_modern
return self.environ['SERVER_PROTOCOL'].upper() != 'HTTP/0.9'
TypeError: 'NoneType' object is not subscriptable
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.4/socketserver.py", line 305, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 331, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 344, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3.4/socketserver.py", line 669, in __init__
self.handle()
File "/usr/lib/python3.4/wsgiref/simple_server.py", line 133, in handle
handler.run(self.server.get_app())
File "/usr/lib/python3.4/wsgiref/handlers.py", line 144, in run
self.close()
File "/usr/lib/python3.4/wsgiref/simple_server.py", line 35, in close
self.status.split(' ',1)[0], self.bytes_sent
AttributeError: 'NoneType' object has no attribute 'split'
This output doesn't actually include the script I am running, which I am confused about. Any thoughts?

Just to register the solution for this issue, the problem is with len() function.
str(len(body))
It calculate the wrong size and when return the server Content-Length, then it wait more bytes that needed.
Thus, always send bytes using a buffer with UTF-8, follow example:
from io import StringIO
stdout = StringIO()
print("Hello world!", file=stdout)
start_response("200 OK", [('Content-Type', 'text/plain; charset=utf-8')])
return [stdout.getvalue().encode("utf-8")]

Looking at your code I don't see a direct reason for this error. However, I would strongly advise that unless you're trying to learn how wsgi works (or implement your own framework), you should use an existing micro-framework. WSGI is NOT meant to be used directly by applications. It provides a very thin interface between Python and a web server.
A nice and light framework is bottle.py -- I use it for all Python webapps. But there are many many others, look for "Non Full-Stack Frameworks" in https://wiki.python.org/moin/WebFrameworks.
A nice advantage of bottle is that it's a single file, which makes it easy to distribute with your server.

Flask: Server becomes unresponsive after some time

I use a flask server to serve static files from a server but once in a while the server becomes completely unresponsive, downloading a file keeps loading but never downloads. When I opened up the terminal, I found some weird requests, I hit CTRL + C and the server immediately becomes responsive again and downloads continue. This happens every so often and I have no idea what's causing this and how to prevent it from freezing my flask server, is this someone trying to hack?
user#server:~/worker# python server.py
* Running on http://0.0.0.0:80/
93.134.13.318 - - [03/Sep/2014 02:07:18] code 400, message Bad request syntax ('\x00')
93.134.13.318 - - [03/Sep/2014 02:07:18] "" 400 -
93.134.13.318 - - [03/Sep/2014 02:07:19] "GET http://httpheader.net HTTP/1.1" 404 -
93.134.13.318 - - [03/Sep/2014 02:07:40] code 400, message Bad request syntax ('\x04\x01\x00P\xc6\xce\x0eu0\x00')
93.174.93.218 - - [03/Sep/2014 02:07:40] "P��u0" 400 -
^C----------------------------------------
Exception happened during processing of request from ('93.174.93.218 ', 45082)
Traceback (most recent call last):
File "/usr/lib/python2.7/SocketServer.py", line 284, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.7/SocketServer.py", line 310, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.7/SocketServer.py", line 323, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.7/SocketServer.py", line 638, in __init__
self.handle()
File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 200, in handle
rv = BaseHTTPRequestHandler.handle(self)
File "/usr/lib/python2.7/BaseHTTPServer.py", line 340, in handle
self.handle_one_request()
File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 231, in handle_one_request
self.raw_requestline = self.rfile.readline()
File "/usr/lib/python2.7/socket.py", line 447, in readline
data = self._sock.recv(self._rbufsize)
KeyboardInterrupt
----------------------------------------
42.36.63.90 - - [03/Sep/2014 03:21:20] "GET / HTTP/1.1" 404 -
63.63.193.195 - - [03/Sep/2014 03:21:20] "GET / HTTP/1.1" 404 -

I had the same issue. It's common in django/flask apps to hang when running as python server.py, because this in not an optimal environment for them. Only use it for testing purpose. When you're done with it and want to release, you should put it behind a wsgi/uwsgi + apache/nginx and your problem will go away.
http://flask.pocoo.org/docs/0.10/deploying/uwsgi/
http://flask.pocoo.org/docs/1.0/deploying/uwsgi/

Django File based session - filename too long

I'm using Django==1.1 (i have to)
and file based session. I get following traceback (below)
I know that during initialization of django.contrib.sessions.backends.file.SessionStore the constructor is getting very long session_key.
But where this class instance is created - I don't know. I'm trying to find out. And why the heck so long session_key is created?
Traceback (most recent call last):
File "/Users/john/.virtualenvs/app/lib/python2.7/site-packages/django/core/servers/basehttp.py", line 279, in run
self.result = application(self.environ, self.start_response)
File "/Users/john/.virtualenvs/app/lib/python2.7/site-packages/django/core/servers/basehttp.py", line 651, in __call__
return self.application(environ, start_response)
File "/Users/john/.virtualenvs/app/lib/python2.7/site-packages/django/core/handlers/wsgi.py", line 245, in __call__
response = middleware_method(request, response)
File "/Users/john/.virtualenvs/app/lib/python2.7/site-packages/django/contrib/sessions/middleware.py", line 36, in process_response
request.session.save()
File "/Users/john/.virtualenvs/app/lib/python2.7/site-packages/django/contrib/sessions/backends/file.py", line 88, in save
fd = os.open(session_file_name, flags)
OSError: [Errno 63] File name too long: '/tmp/sessionid.eJydVktv4zYQ9m63Fx7aQ3-EfXJFvYWeit1FkYuLrpNuDwsQlMTQSmRJJqU4KVCgP70zQ8mPxMmhB8kWh5z55psX_33_z-7d4uaDaWv11_ez2UyW26rZvb_5wQpTVo224raUvdx9d_3Tu9lsUXacrefNsM2VEfmcdT5b2fXc9tL0AjaqvtoqWA5YMX2xw58uZIv1_Nujl3x7LAv4jeDh8HiXnjkruqf-byY61kV48PNg2k79_FUaK_dgI2ZXie957CqI4b2ef_y8voblhPVfuhRfGbMHrBIkHPb6foCrqilP4XLO9AVwHJ_kl5fINOnnPrPLmx-PTFV1r8zuw_VvbDYrirZ7EkZpBq-ibWxvhqJvDRhji6K8k41ul2W-3Lalqu3S7urlblDmif1BbyC2ECIfQGXVCMHa_E4VPRK7AsuAtQRS1nOpNZgAR4RVNWwQW2nviRsMi3ghLmSxUUQSytVjb5CYlOkTUENfASCMusM8GGXZujW9Kj9ViCE7h1bSIpC7KJEUjtiAmvX8Xj39bkplkOCALeqOh8zmYPeuhYNb2aEgou0xW6z-RJ4clbAOCFd9x1O20PAf_kE04ahRNbhTTv7cVqouLeahhwZ8zia3RC_zWpHIZ4sek5SO4AKB8UPcuxtaYGeixSc0fszI0oM4AeonJEKqEnhSQjNYgCLrSlpn6RkzVmHEABmYCzidlEBR4KP-FqkR-RNWCwEKCFBZWThMOIOIXUFm4-LQKSEf2qqUTUH1FSOaICGhupVD3QtSCOyhOIWTxIU27dCNVjJXqyNzrRFDhzUAotCbLI3SkWYU8QMIdauMAYfrVpbOTgjUaucgZmVAVvsuDE9UHUIURuhlSOQSZyOzITEbOmYXjl6M_mqFhkGbi_xWPopSdf0GjkSAN2Ku8TSlNOWp8xGfnHeJcEJ0NKbCRPIRXEQhiAj4IXMiQhzFLnL2pNxImlDZ6Ax-xuSPUipMXCF9secS3gF5VqL8cjhE0-5lhfGP_Yl6caZgytY4IA11uwedhnSGcOLIr1G3RTs0pCs6B9vFzqsraIcAPKYYxOkBeDb6nL-suaKt0f2EKi7hpyk4ifwpAlNYTookIQMJMb2RDy5mSXTWgs774n6jjGJf8b2CVdgN2F0jTAh3kkK3gR7bKOywqC6DhV9Xn7C3ER8NRQ3zOT3kc7Gp6tKoBhd9xJTSaLBD3hulRCdB1iPiNCRp5GIJeVMPJdBRNYCoQmIcVtxJZZkmhywaUzylvEgdqaAr80Z6YR95J4oaPmBnBm0ioRIhpbgCk2BfGdXLrhtZYV-mTgliAk1KcHPownxkKKOWlsE3kKKRDT1RoJ3bWfLiDMHNstfPcM97foh7rvN7_lvHAqzwtwP9kYalrBqaKuFRvxsVXszG_KaR7rqF1UCTdlxQTYtGusnuYW64-8k07D26GECu0uRHR3Alh2aJzfDSxYXjBQFf__P-wmEeXrjBcCi2i3cYDpOSZmnkfmIcgJQw2iUjxwGUy-chgCFJw9d7IwQ-dyHQp9zijMSDAZLxnFLtSDy9SeHw1I47_JuPFNt9hf0Zi59uWoAaRuoRNU7Wl6jdaOU4W19HnV1AHVAn4zRaL6N2odVnUa4xyvr1kL5-65viAQMcPIOpffQMh3d-8hmdf8aud2wqvZl6NQ_cJczdGkVlBcyk4v6JRKnzPl8Oy_8ACepvHw:1SWRxQ:eJ6zYlFnV8NFqaM2mjeYJUjvBlM'
[22/May/2012 15:45:43] "GET /login/ HTTP/1.1" 500 2736

The request.session gets constructed in SessionMiddleware.process_request, you could check in the file django/contrib/sessions/middleware.py. In early versions,(just checked in recent Django its still vulnerable), there are few checking upon the incoming session key in request.COOKIES, before touching the backend, thus you got a over-long one that fails session.save().