CODEWITHSUNDEEP
localhostportcherrypy
Alex
Alex

Reputation: 44709

CherryPy Hello World error

When I am running CherryPy Hello World:

import cherrypy

class HelloWorld:
    def index(self):
        return "Hello world!"
    index.exposed = True

cherrypy.config.update({'server.socket_port': 8080,})
cherrypy.quickstart(HelloWorld())

... I get this: IOError: Port 8080 not bound on 'localhost'. What could it be?

Upvotes: 13

Views: 14281

Answers (10)

Daniel Donnelly
Daniel Donnelly

Reputation: 610

Windows 10

If you get a python exception printed to stdio that 8080 is not free on 127.0.0.1, then what you do is this:

netstat -o -a

at the windows command prompt. Doing netstat -o alone will give you an incorrect PID.

Look for 8080 in the address string in the first column. Once found, go horizontally over to the last column which is the PID (process ID).

Now to kill a process, I use kill <PID> which is part of an mysys install. I found that out by doing where kill on my system.

Thus all together:

netstat -o -a
[find PID then hit ctrl-c to stop netstat]
kill 13164

where 13164 is an example PID found in the first step.

If you do not have mysys installed, then install it or else look up how to kill a process by its PID on windows.

Upvotes: 0

Tomh
Tomh

Reputation: 342

If you're on OS X, try calling:

sudo lsof -i :8080

which will tell you the process using that port.

Upvotes: 1

Dzmitry
Dzmitry

Reputation: 1471

I had the same problem when running CherryPy 3.2.2 on my Win7 PC with Python 3.3 The server would start normally and then would crash in about a couple of minutes.

I've applied the patch from CherryPy 3.2.3 laurasia mentioned. But it didn't help.

So I had to comment out the lines raising the error at the very end of python\Lib\site-packages\cherrypy\process\servers.py to prevent the server from dying:

...
#    if host == client_host(host):
#        raise IOError("Port %r not bound on %r" % (port, host))
...

Upvotes: 0

Jason R. Coombs
Jason R. Coombs

Reputation: 42659

I ran into this problem yesterday on an Ubuntu Linux server. I spent a couple of hours trying to track down the bug in the CherryPy code before I realized that the error message is very generic. It will give this error message even if the host doesn't own the IP address to which the server is attempting to bind. In my case, the loopback interface (lo, 127.0.0.1) was disabled. Thus, even if I set server.socket_host='0.0.0.0', the attempt to check the port, wait_for_occupied_port, would fail (as it assumes, reasonably, that the loopback interface is always available). After re-enabling the loopback interface, the CherryPy server would start up normally.

Update: CherryPy 3.2.3 has a fix for this particular issue. Until 3.2.3 is released, development builds are available on the CherryPy project downloads.

Upvotes: 2

laurasia
laurasia

Reputation: 686

As Jason R. Coombs wrote there is a problem with disabled loopback device. heroku.com has loopback disabled therefore CherryPy will crash. I filed a bug for this.

Update: Reported as resolved.

Upvotes: 3

Brandon Rhodes
Brandon Rhodes

Reputation: 89405

If you are trying to deploy CherryPy on Heroku, where you cannot use the loopback to check whether you have really opened a port, then you need to simply disable CherryPy's wait_for_occupied_port() function so that CherryPy's self-consistency check does not decide that it has, in fact, failed to start. Here are the three lines that I use to fix CherryPy so that it runs on Heroku:

    from cherrypy.process import servers
    def fake_wait_for_occupied_port(host, port): return
    servers.wait_for_occupied_port = fake_wait_for_occupied_port

Upvotes: 9

Glen Richards
Glen Richards

Reputation:

AVG Anti-Virus was causing this problem for me. Uninstalling AVG (far from ideal) did the trick. I suspect the link scanner that I couldn't disable.

Upvotes: 0

joce
joce

Reputation: 9892

I think I had a similar problem when I started using CherryPy... But I can't remember exactly what it was... But the fix involved using a config file instead of passing the configs by hand:

MyProj.conf:

[global]
server.socket_host = "127.0.0.1"
server.socket_port = 8080
server.thread_pool = 10

MyProj.py

import os
import cherrypy

class HelloWorld:
    def index(self):
        return "Hello world!"
    index.exposed = True

# Assumes the config file is in the directory as the source.    
conf_path = os.path.dirname(os.path.abspath(__file__))
conf_path = os.path.join(conf_path, "MyProj.conf")
cherrypy.config.update(conf_path)
cherrypy.quickstart(HelloWorld())

This definitely works here.
I'm using Python 2.6.1 and CherryPy 3.1.1 and I run the script with -W ignore: 

c:\My_path> python -W ignore MyProj.py

If you're under *nix, you should put the -W ignore in the #! comment at the top of the file.

Upvotes: 2

Alex Bolotov
Alex Bolotov

Reputation: 8971

  • Use it on different port (8000 for example)
  • Read about ConfigApi (once again)
  • Try latest version not 3.0
  • Also this can be caused by some Windows firewall (Eset smart security or maybe other). So just use it on different port.

Upvotes: 1

Douglas Leeder
Douglas Leeder

Reputation: 53310

You've probably got something else listening on that port.

On Linux do:

netstat -pnl | grep 8080

And see what process is listening on 8080

On Windows use something like TCPView to do the same.

Upvotes: 7

Related Questions