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How to run one part of code on local and another in production (heroku) in python? [duplicate]

I have a Django webapp, and I'd like to check if it's running on the Heroku stack (for conditional enabling of debugging, etc.) Is there any simple way to do this? An environment variable, perhaps?
I know I can probably also do it the other way around - that is, have it detect if it's running on a developer machine, but that just doesn't "sound right".

An ENV var seems to the most obvious way of doing this. Either look for an ENV var that you know exists, or set your own:
on_heroku = False
if 'YOUR_ENV_VAR' in os.environ:
on_heroku = True
more at: http://devcenter.heroku.com/articles/config-vars

Similar to what Neil suggested, I would do the following:
debug = True
if 'SOME_ENV_VAR' in os.environ:
debug = False
I've seen some people use if 'PORT' in os.environ: But the unfortunate thing is that the PORT variable is present when you run foreman start locally, so there is no way to distinguish between local testing with foreman and deployment on Heroku.
I'd also recommend using one of the env vars that:
Heroku has out of the box (rather than setting and checking for your own)
is unlikely to be found in your local environment
At the date of posting, Heroku has the following environ variables:
['PATH', 'PS1', 'COLUMNS', 'TERM', 'PORT', 'LINES', 'LANG', 'SHLVL', 'LIBRARY_PATH', 'PWD', 'LD_LIBRARY_PATH', 'PYTHONPATH', 'DYNO', 'PYTHONHASHSEED', 'PYTHONUNBUFFERED', 'PYTHONHOME', 'HOME', '_']
I generally go with if 'DYNO' in os.environ:, because it seems to be the most Heroku specific (who else would use the term dyno, right?).
And I also prefer to format it like an if-else statement because it's more explicit:
if 'DYNO' in os.environ:
debug = False
else:
debug = True

First set the environment variable ON_HEROKU on heroku:
$ heroku config:set ON_HEROKU=1
Then in settings.py
import os
# define if on heroku environment
ON_HEROKU = 'ON_HEROKU' in os.environ

Read more about it here: https://devcenter.heroku.com/articles/config-vars
My solution:
$ heroku config:set HEROKU=1
These environment variables are persistent – they will remain in place across deploys and app restarts – so unless you need to change values, you only need to set them once.
Then you can test its presence in your app.:
>>> 'HEROKU' in os.environ
True

The most reliable way would be to set an environment variable as above.
If that's not possible, there are a few signs you can look for in the filesystem, but they may not be / are not foolproof
Heroku instances all have the path /app - the files and scripts that are running will be under this too, so you can check for the presence of the directory and/or that the scripts are being run from under it.
There is an empty directory /etc/heroku
/etc/hosts may have some heroku related domains added
~ $ cat /etc/hosts
<snip>.dyno.rt.heroku.com
Any of these can and may change at any moment.
Your milage may vary

DATABASE_URL environment variable
in_heroku = False
if 'DATABASE_URL' in os.environ:
in_heroku = True
I think you need to enable the database for your app with:
heroku addons:create heroku-postgresql:hobby-dev
but it is free and likely what you are going to do anyways.
Heroku makes this environment variable available when running its apps, in particular for usage as:
import dj_database_url
if in_heroku:
DATABASES = {'default': dj_database_url.config()}
else:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}
Not foolproof as that variable might be defined locally, but convenient for simple cases.
heroku run env
might also show other possible variables like:
DYNO_RAM
WEB_CONCURRENCY
but I'm not sure if those are documented like DATABASE_URL.

Short version: check that the time zone is UTC/GMT:
if not 'ORIGINAL_TIMEZONE' in os.environ:
f = os.popen('date +%Z')
tz = f.read().upper()
os.environ['ORIGINAL_TIMEZONE']=tz
tz = os.environ['ORIGINAL_TIMEZONE']
if tz != '' and (not 'utc' in tz.lower()) and (not 'gmt' in tz.lower()):
print 'Definitely not running on Heroku (or in production in general)'
else:
print 'Assume that we are running on Heroku (or in production in general)'
This is more conservative than if tz=='UTC\n': if in doubt, assume that we are in production. Note that we are saving the timezone to an environment variable because settings.py may be executed more than once. In fact, the development server executes it twice, and the second time the system timezone is already 'UTC' (or whatever is in settings.TIMEZONE).
Long version:
making absolutely sure that we never run on Heroku with DEBUG=True, and that we never run the development server on Heroku even with DEBUG=False. From settings.py:
RUNNING_DEV_SERVER = (len(sys.argv) > 1) and (sys.argv[1] == 'runserver')
DEBUG = RUNNING_DEV_SERVER
TEMPLATE_DEBUG = DEBUG
# Detect the timezone
if not 'ORIGINAL_TIMEZONE' in os.environ:
f = os.popen('date +%Z')
tz = f.read().upper()
os.environ['ORIGINAL_TIMEZONE']=tz
print ('DEBUG: %d, RUNNING_DEV_SERVER: %d, system timezone: %s ' % (DEBUG, RUNNING_DEV_SERVER, tz))
if not (DEBUG or RUNNING_DEV_SERVER):
SECRET_KEY = os.environ['SECRET_KEY']
else:
print 'Running in DEBUG MODE! Hope this is not in production!'
SECRET_KEY = 'DEBUG_INSECURE_SECRET_KEY_ae$kh(7b%$+a fcw_bdnzl#)$t88x7h2-p%eg_ei5m=w&2p-)1+'
# But what if we are idiots and are still somehow running with DEBUG=True in production?!
# 1. Make sure SECRET_KEY is not set
assert not SECRET_KEY in os.environ
# 2. Make sure the timezone is not UTC or GMT (indicating production)
tz = os.environ['ORIGINAL_TIMEZONE']
assert tz != '' and (not 'UTC' in tz) and (not 'GMT' in tz)
# 3. Look for environment variables suggesting we are in PROD
for key in os.environ:
for red_flag in ['heroku', 'amazon', 'aws', 'prod', 'gondor']:
assert not red_flag in key.lower()
assert not red_flag in os.environ[key].lower()
If you really want to run the development server on Heroku, I suggest you add an environment variable specifying the date when you can do that. Then only proceed if this date is today. This way you'll have to change this variable before you begin development work, but if you forget to unset it, next day you will still be protected against accidentally running it in production. Of course, if you want to be super-conservative, you can also specify, say, a 1-hour window when exceptions apply.
Lastly, if you decided to adopt the approach suggested above, while you are at it, also install django-security, add djangosecurity to INSTALLED_APPS, and add to the end of your settings.py:
if not (DEBUG or RUNNING_DEV_SERVER):
### Security
SECURE_SSL_REDIRECT = True
SECURE_CONTENT_TYPE_NOSNIFF = True
SECURE_HSTS_SECONDS = 86400000
SECURE_HSTS_INCLUDE_SUBDOMAINS = True
SECURE_BROWSER_XSS_FILTER = True
SESSION_COOKIE_SECURE = True
SESSION_COOKIE_HTTPONLY = True
CSRF_COOKIE_HTTPONLY = True # May have problems with Ajax
CSRF_COOKIE_SECURE = True

Output cluttered with profiling:skip messages

Every time I run any python script (.py) in my Cygwin (bash) shell, I get a huge list of profling: ... :Skip. I don't think it's Cygwin-related, but something with my Python setup, which is installed from the official Cygwin repos & builds.
Python itself is functioning correctly but these messages clutter my output.
How can I fix/remove them?
[admin#Zbook ~/Desktop]λ python3.8 --version
Python 3.8.2
profiling:/usr/local/src/Python-3.8.2/Programs/python.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/getbuildinfo.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/acceler.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/grammar1.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/listnode.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/node.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/parser.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/token.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/myreadline.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/parsetok.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Parser/tokenizer.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/abstract.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/accu.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/boolobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/bytes_methods.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/bytearrayobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/bytesobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/call.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/capsule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/cellobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/classobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/codeobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/complexobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/descrobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/enumobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/exceptions.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/genobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/fileobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/floatobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/frameobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/funcobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/interpreteridobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/iterobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/listobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/longobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/dictobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/odictobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/memoryobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/methodobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/moduleobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/namespaceobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/object.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/obmalloc.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/picklebufobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/rangeobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/setobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/sliceobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/structseq.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/tupleobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/typeobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/unicodeobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/unicodectype.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Objects/weakrefobject.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/_warnings.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/Python-ast.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/asdl.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/ast.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/ast_opt.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/ast_unparse.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/bltinmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/ceval.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/codecs.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/compile.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/context.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/errors.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/frozenmain.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/future.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getargs.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getcompiler.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getcopyright.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getplatform.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getversion.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/hamt.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/import.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/importdl.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/initconfig.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/marshal.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/modsupport.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/mysnprintf.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/mystrtoul.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pathconfig.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/peephole.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/preconfig.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pyarena.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pyfpe.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pyhash.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pylifecycle.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pymath.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pystate.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pythonrun.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pytime.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/bootstrap_hash.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/structmember.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/symtable.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/sysmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/thread.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/traceback.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/getopt.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pystrcmp.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pystrtod.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/pystrhex.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/dtoa.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/formatter_unicode.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/fileutils.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Python/dynload_shlib.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/getpath.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/main.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/gcmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/posixmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/errnomodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/pwdmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_sre.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_codecsmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_weakref.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_functoolsmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_operator.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_collectionsmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_abc.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/itertoolsmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/atexitmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/signalmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_stat.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/timemodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_threadmodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_localemodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_iomodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/iobase.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/fileio.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/bytesio.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/bufferedio.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/textio.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/stringio.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/faulthandler.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/_tracemalloc.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/hashtable.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/symtablemodule.gcda:Skip
profiling:/usr/local/src/Python-3.8.2/Modules/xxsubtype.gcda:Skip

#matzeri is right! Turns out I had an old & partial Python 3.8 installation which I compiled from source long ago and totally forgot about it!
Cited messages in the output are because of the --enable-optimizations and maybe the --disable-profiling compilation flags.
I used this bash script from Stack Exchange to clear this old compiled-from-source Python!

Locale on django and uwsgi UnicodeEncodeError

EDIT: I just realized, that when i'm not trying to print to console that variable, it works. Why?
I run into an issue related to displaying string label with utf chars. I set locale env in uwsgi ini file like this:
env =LC_ALL=en_US.UTF-8
env =LANG=en_US.UTF-8
and in wsgi.py:
locale.setlocale(locale.LC_ALL, 'en_US.UTF-8')
When I run app code:
print (locale.getlocale(), locale.getpreferredencoding())
print locale.getdefaultlocale()
print "option_value", option_value
label = force_text(option_label)
print 'label', label #THIS FAILS
the output is:
(('en_US', 'UTF-8'), 'UTF-8')
('en_US', 'UTF-8')
option_value d
ERROR <stack trace>
print 'label', label
UnicodeEncodeError: 'ascii' codec can't encode character u'\u015b' in position 5: ordinal not in range(128)
The problem is not present when I run app via runserver in production environment.
Django 1.6.5 Python 2.7.6 Ubuntu 14.04 uWSGI 2.0.5.1

I just found answer here: http://chase-seibert.github.io/blog/2014/01/12/python-unicode-console-output.html
Realized that the console is responsible for that error, so exporting additional env variable in uwsgi config file solves the issue: env = PYTHONIOENCODING=UTF-8

for all in django when you want use unicode , like in forms and etc .. you must set a u in leading of your unicode that you want to be saved ! do this any where that your unicode have been saved !
in this case i think it is (option_label)

How do I deploy web2py on PythonAnywhere?

How do i get a basic web2py server up and running on
PythonAnywhere?

[update - 29/05] We now have a big button on the web tab that will do all this stuff for you. Just click where it says Web2Py, fill in your admin password, and you're good to go.
Here's the old stuff for historical interest...
I'm a PythonAnywhere developer. We're not massive web2py experts (yet?) but I've managed to get web2py up and running like this:
First download and unpack web2py:
wget http://www.web2py.com/examples/static/web2py_src.zip
unzip web2py_src.zip
Go to the PythonAnywhere "Web" panel and edit your wsgi.py. Add these lines:
import os
import sys
path = '/home/my_username/web2py'
if path not in sys.path:
sys.path.append(path)
from wsgihandler import application
replacing my_username with your username.
You will also need to comment out the last two lines in wsgi.py, where we have the default hello world web.py application...
# comment out these two lines if you want to use another framework
#app = web.application(urls, globals())
#application = app.wsgifunc()
Thanks to Juan Martinez for his instructions on this part, which you can view here:
http://web2py.pythonanywhere.com/
then open a Bash console, and cd into the main web2py folder, then run
python web2py.py --port=80
enter admin password
press ctrl-c
(this will generate the parameters_80.py config file)
then go to your Web panel on PythonAnywhere, click reload web app,
and things should work!

You can also simply run this bash script:
http://pastebin.com/zcA5A89k
admin will be disabled because of no HTTPS unless you bypass it as in the previous post. It will create a security vulnerability.

Pastebin was down, I retrieved this from the cache.
cd ~
wget -O web2py_srz.zip http://web2py.com/examples/static/web2py_src.zip
unzip web2py_src.zip
echo "
PATH = '/home/"`whoami`"/web2py'
import os
import sys
sys.stdout = sys.stderr
os.chdir(PATH)
if not './' in sys.path[:1]: sys.path.insert(0,'./')
from gluon.main import wsgibase as application
" > /var/www/wsgi.py
cd web2py
python -c "from gluon.main import save_password; save_password(raw_input('admin password: '),433)"

I have recently summarized my experience with deployment of Web2Py on PythonAnywhere here
Hope it helps
NeoToren

I'll try to add something new to the discussion. The EASIEST way I've found is to go here when you aren't logged in. This makes it so you don't have to mess around with the terminal:
https://www.pythonanywhere.com/try-web2py
Come up with a domain name, then you'll get redirected to a page showing your login information and created dashboard for that domain. From there just create an account so your app isn't erased after 24 hours. When you sign up, your app has a 3 month expiry date (if you're not paying). I believe this is a new policy. Then simply go to https://appname.pythonanywhere.com/admin and then enter the password you were given and then upload your Web2Py file into the dashboard and then visit the page.
I'm not sure how to upload a Web2Py app on PythonAnywhere for an existing account, but that's the easiest method I've found.

CherryPy3 and IIS 6.0

I have a small Python web application using the Cherrypy framework. I am by no means an expert in web servers.
I got Cherrypy working with Apache using mod_python on our Ubuntu server. This time, however, I have to use Windows 2003 and IIS 6.0 to host my site.
The site runs perfectly as a stand alone server - I am just so lost when it comes to getting IIS running. I have spent the past day Googling and blindly trying any and everything to get this running.
I have all the various tools installed that websites have told me to (Python 2.6, CherrpyPy 3, ISAPI-WSGI, PyWin32) and have read all the documentation I can. This blog was the most helpful:
http://whatschrisdoing.com/blog/2008/07/10/turbogears-isapi-wsgi-iis/
But I am still lost as to what I need to run my site. I can't find any thorough examples or how-to's to even start with. I hope someone here can help!
Cheers.

I run CherryPy behind my IIS sites. There are several tricks to get it to work.
When running as the IIS Worker Process identity, you won't have the same permissions as you do when you run the site from your user process. Things will break. In particular, anything that wants to write to the file system will probably not work without some tweaking.
If you're using setuptools, you probably want to install your components with the -Z option (unzips all eggs).
Use win32traceutil to track down problems. Be sure that in your hook script that you're importing win32traceutil. Then, when you're attempting to access the web site, if anything goes wrong, make sure it gets printed to standard out, it'll get logged to the trace utility. Use 'python -m win32traceutil' to see the output from the trace.
It's important to understand the basic process to get an ISAPI application running. I suggest first getting a hello-world WSGI application running under ISAPI_WSGI. Here's an early version of a hook script I used to validate that I was getting CherryPy to work with my web server.
#!python
"""
Things to remember:
easy_install munges permissions on zip eggs.
anything that's installed in a user folder (i.e. setup develop) will probably not work.
There may still exist an issue with static files.
"""
import sys
import os
import isapi_wsgi
# change this to '/myapp' to have the site installed to only a virtual
# directory of the site.
site_root = '/'
if hasattr(sys, "isapidllhandle"):
import win32traceutil
appdir = os.path.dirname(__file__)
egg_cache = os.path.join(appdir, 'egg-tmp')
if not os.path.exists(egg_cache):
os.makedirs(egg_cache)
os.environ['PYTHON_EGG_CACHE'] = egg_cache
os.chdir(appdir)
import cherrypy
import traceback
class Root(object):
#cherrypy.expose
def index(self):
return 'Hai Werld'
def setup_application():
print "starting cherrypy application server"
#app_root = os.path.dirname(__file__)
#sys.path.append(app_root)
app = cherrypy.tree.mount(Root(), site_root)
print "successfully set up the application"
return app
def __ExtensionFactory__():
"The entry point for when the ISAPIDLL is triggered"
try:
# import the wsgi app creator
app = setup_application()
return isapi_wsgi.ISAPISimpleHandler(app)
except:
import traceback
traceback.print_exc()
f = open(os.path.join(appdir, 'critical error.txt'), 'w')
traceback.print_exc(file=f)
f.close()
def install_virtual_dir():
import isapi.install
params = isapi.install.ISAPIParameters()
# Setup the virtual directories - this is a list of directories our
# extension uses - in this case only 1.
# Each extension has a "script map" - this is the mapping of ISAPI
# extensions.
sm = [
isapi.install.ScriptMapParams(Extension="*", Flags=0)
]
vd = isapi.install.VirtualDirParameters(
Server="CherryPy Web Server",
Name=site_root,
Description = "CherryPy Application",
ScriptMaps = sm,
ScriptMapUpdate = "end",
)
params.VirtualDirs = [vd]
isapi.install.HandleCommandLine(params)
if __name__=='__main__':
# If run from the command-line, install ourselves.
install_virtual_dir()
This script does several things. It (a) acts as the installer, installing itself into IIS [install_virtual_dir], (b) contains the entry point when IIS loads the DLL [__ExtensionFactory__], and (c) it creates the CherryPy WSGI instance consumed by the ISAPI handler [setup_application].
If you place this in your \inetpub\cherrypy directory and run it, it will attempt to install itself to the root of your IIS web site named "CherryPy Web Server".
You're also welcome to take a look at my production web site code, which has refactored all of this into different modules.

OK, I got it working. Thanks to Jason and all his help. I needed to call
cherrypy.config.update({
'tools.sessions.on': True
})
return cherrypy.tree.mount(Root(), '/', config=path_to_config)
I had this in the config file under [/] but for some reason it did not like that. Now I can get my web app up and running - then I think I will try and work out why it needs that config update and doesn't like the config file I have...