CherryPy Hello World error

Question

When I am running CherryPy Hello World:

import cherrypy

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

che         


        

Answer 1

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

Answer 2

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.

Answer 3

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.

Answer 4

If you're on OS X, try calling:

sudo lsof -i :8080

which will tell you the process using that port.

Answer 5

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.

Answer 6

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.