Django with Passenger - python

I'm trying to get a trivial Django project working with Passenger on Dreamhost, following the instructions here
I've set up the directories exactly as in that tutorial, and ensured that django is on my PYTHONPATH (I can run python and type 'import django' without any errors). However, when I try to access the url in a browser, I get the following message: "An error occurred importing your passenger_wsgi.py". Here is the contents of my passenger_wsgi.py file:
import sys, os
sys.path.append("/path/to/web/root/") # I used the actual path in my file
os.environ['DJANGO_SETTINGS_MODULE'] = ‘myproject.settings’
import django.core.handlers.wsgi
application = django.core.handlers.wsgi.WSGIHandler()
However, when I put the following simple "Hello World" application in passenger_wsgi.py, it works as intended, suggesting Passenger is set up correctly:
def application(environ, start_response):
write = start_response('200 OK', [('Content-type', 'text/plain')])
return ["Hello, world!"]
What am I missing? Seems like some config issue.

Are those fancy quotation marks also in your code?
os.environ['DJANGO_SETTINGS_MODULE'] = ‘myproject.settings’
^ ^
If so, start by fixing them, as they cause a syntax error.

Related

Bottle not routing to index html file

I'm using Bottle for a Python project and I've set the project to run on the localhost:8080 (Windows 10 laptop). I’ve coded the project on VS Code, however, when I start the debugger on VS Code’s integrated terminal,I am presented with Error 500 on my browser (Google Chrome).
The project worked fine on a TA's machine, however on my laptop, bottle isn't routing to the index page, even when I explicitly had it import it from the static_file and adding the root file to the ‘run’ function. I tried running the example from Bottlepy.org, and even that isn’t working.
The only thing that has worked was:
from bottle import run, route
#route('/')
def hello():
return "If you're seeing this message, then bottle is working"
run(host='localhost', port=8080)
Again, I’ve ran:
from bottle import run, route, template
#route('/')
def hello():
return template("index.html")
run(host='localhost', port=8080)
and
from bottle import run, route, static_file
#route('/static/')
def hello():
return static_file('index.html', root='static')
run(host='localhost', port=8080)
Including the example from bottlepy.org, to which resulted in:
Error 500 Template 'index.html' not found.
Or
Error 500 ‘Template ‘/’ not found
I don’t believe it’s a PATH issue with Python, but it could be a JSON file issue with VS code. All the Python packages on my machine are updated and I’m out of ideas at the moment. Your suggestions/recommendations would be appreciated. Thank you.
Probably the issue is because the integrated shell executes the code in some other directory where the file 'index.html' is.
To help solve the issue, replace the file name with an absolute path, e.g.
#route('/static/')
def hello():
return static_file(os.path.join(os.path.dirname(__file__), 'index.html'), root='static')

Django passenger_wsgi.py issue

I run Django on an A2 Hosting Linux shared hosting account. Previously, I was using an old version of Django and Python. I was also using FCGI. I recently changed to a new server and am now using Django 2.1.2, Python 3.6.0. and Phusion Passenger.
I can't get the passenger_wsgi.py to load my website and I can't find the error log to try and resolve the problem.
The .htaccess file is in the public_html directory.
My app files are stored in:
/home/username/example.com/
The folder/file structure in the example.com directory is:
-media
-mysite
--- init.py
--- settings.py
--- urls.py
--- wsgi.py
-public
-tmp
-manage.py
-passenger_wsgi.py
#
The contents of the passenger_wsgi.py file:
import os
import sys
import mysite.wsgi
application = mysite.wsgi.application
cwd = os.getcwd()
sys.path.append(cwd)
#sys.path.append(os.getcwd())
sys.path.append(cwd + '/mysite')
SCRIPT_NAME = os.getcwd()
class PassengerPathInfoFix(object):
"""
Sets PATH_INFO from REQUEST_URI since Passenger doesn't provide it.
"""
def __init__(self, app):
self.app = app
def __call__(self, environ, start_response):
from urllib.parse import unquote
environ['SCRIPT_NAME'] = SCRIPT_NAME
request_uri = unquote(environ['REQUEST_URI'])
script_name = unquote(environ.get('SCRIPT_NAME', ''))
offset = request_uri.startswith(script_name) and len(environ['SCRIPT_NAME']) or 0
environ['PATH_INFO'] = request_uri[offset:].split('?', 1)[0]
return self.app(environ, start_response)
application = PassengerPathInfoFix(application)
The site produces an error (image below). I've been trying to fix it all day by tinkering with the passenger_wsgi.py file.
I can't find the Passenger error log file. I don't have any experience with Passenger. I've run out of ideas of ways to try and resolve the issue.
When I run 'python passenger_wsgi.py' in SSH, no comments are produced.
If anyone could help me to either:
(1) Identify what is wrong with the passenger_wsgi.py content or
(2) How I can find the Passenger error log on a shared Linux hosting account.
Not sure it'll be possible to diagnose anything without logs, but I've had the similar issues on shared A2 Hosting finding logs. I was able to find some Passenger logs in the "Errors" section of cPanel.
On the cPanel home screen, scroll down to the "Metric" subheader. There will be a link for "Errors" in this section. You should be able to find critical Passenger logs there.
This structure of passenger_wsgi.py works for me on A2 Hosting:
import os
import sys
import MyApp.wsgi
SCRIPT_NAME = '/home/user/domain'
class PassengerPathInfoFix(object):
""" Sets PATH_INFO from REQUEST_URI because Passenger doesn't provide it. """
def __init__(self, app):
self.app = app
def __call__(self, environ, start_response):
from urllib.parse import unquote
environ['SCRIPT_NAME'] = SCRIPT_NAME
request_uri = unquote(environ['REQUEST_URI'])
script_name = unquote(environ.get('SCRIPT_NAME', ''))
offset = request_uri.startswith(script_name) and len(environ['SCRIPT_NAME']) or 0
environ['PATH_INFO'] = request_uri[offset:].split('?', 1)[0]
return self.app(environ, start_response)
application = MyApp.wsgi.application
application = PassengerPathInfoFix(application)

code passenger_wsgi python

Can someone explain why this code shows a new version of Python on Dreamhost ?
import sys,os
# Force Passenger to run our virtualenv python
INTERP = "/home/site/env/bin/python"
if sys.executable != INTERP: os.execl(INTERP, INTERP, *sys.argv)
def application(environ, start_response):
start_response('200 OK', [('Content-type', 'text/plain')])
return ["Hello, world!" + sys.version]
While this code shows an old version :
#!/home/site/env/bin/python
import sys
def application(environ, start_response):
start_response('200 OK', [('Content-type', 'text/plain')])
return ["Hello, world!" + sys.version]
If you throw some debugging code in passenger_wsgi.py to write out a log file:
x = open(os.path.expanduser('~/log.log'), 'w')
x.write(repr(sys.argv))
x.close()
and then examine ~/log.log, then you’ll find that the python process that loads passenger_wsgi.py is started by running /dh/passenger/lib/phusion_passenger/wsgi/request_handler.py.
The first line of /dh/passenger/lib/phusion_passenger/wsgi/request_handler.py is
#!/usr/bin/env python
and it loads passenger_wsgi.py by calling
app_module = imp.load_source('passenger_wsgi', 'passenger_wsgi.py')
Since passenger_wsgi.py is loaded as a Python module, the #!/home/site/env/bin/python line at the start of your second passenger_wsgi.py file is treated simply as a Python comment and ignored. The default /usr/bin/python is used instead.
The recommended fix for this is exactly what your first passenger_wsgi.py does: execl the version of Python you actually want. I usually compile Python 2.7 in the shell user’s home directory and use that.
PS: If you’re curious I have some notes about setting up Django on Dreamhost so that you can do continuous deployment…

How to properly install isapi_wsgi on IIS for Python2.7?

I've worked through installing Python as a CGI application on IIS on Windows 7. This is pretty straightforward, but I'd like to use the WSGI stuff, for better flexibility.
I downloaded the archive for isapi_wsgi, unzipped it, and then ran the install as per the instructions, like this:
\python27\python.exe setup.py install
This succeeded:
Then I coded a .py module that had the wsgi glue in it, and tried installing it. This failed like so:
It's a COM Moniker error, and I know that the IIS6-compatible management stuff is based on COM Monikers, which reminded me that there is a pre-req for isapi_wsgi of the IIS6-compatible management stuff. I ran \windows\system32\OptionalFeatures.exe and installed that, then re-ran the .py module and it installed correctly.
C:\dev\wsgi>\Python27\python.exe app1_wsgi.py
Configured Virtual Directory: /wsgi
Installation complete.
Ok, wonderful. Now when I look in the current directory, I see a new DLL named _app1_wsgi.dll, and when I look in IIS Manager I can see a new IIS vdir, and a scriptmap within that vdir for '*', which is mapped to the _app1_wsgi.DLL. All good. But! making a request to http://localhost/wsgi gives me a 500 error.
Through some trial-and-error I see that the .py module that defines my handlers must be in the site-packages directory. I am very surprised by this.
Can I avoid this? Can I simply put the .py module in the same directory as the generated .dll file? Or do I need to deploy all of my python logic to site-packages in order to run it from the WSGI mechanism?
The answer is:
the installation of isapi_wsgi as described in the question, is correct.
with the basic boilerplate of app.py as shown in the example code accompanying isapi_wsgi, the python classes for the web app need to be in the site-packages directory.
it is possible to allow the python source modules to reside in the same directory as with the generated *.dll file, but it requires some special handling in the *wsgi.py file.
a better way to run python on Windows for development purposes is to simply download the Google App Engine and use the builtin dedicated http server. The framework that comes with the GAE SDK handles reloading and allows the .py modules to be placed in particular directories.
If you don't want to download and install the GAE SDK, then you might try the following. Using this code, when a request arrives on isapi_wsgi, the handler looks in the home directory for a py module, and loads it. If the module is already loaded, it checks the file "last modified time" and reloads the module if the last mod time is later than the time from the prior load. It works for simplistic cases but I suppose it will be brittle when there are nested module dependencies.
import sys
import os
import win32file
from win32con import *
# dictionary of [mtime, module] tuple; uses file path as key
loadedPages = {}
def request_handler(env, start_response):
'''Demo app from wsgiref'''
cr = lambda s='': s + '\n'
if hasattr(sys, "isapidllhandle"):
h = None
# get the path of the ISAPI Extension DLL
hDll = getattr(sys, "isapidllhandle", None)
import win32api
dllName = win32api.GetModuleFileName(hDll)
p1 = repr(dllName).split('?\\\\')
p2 = p1[1].split('\\\\')
sep = '\\'
homedir = sep.join(p2[:-1])
# the name of the Python module is in the PATH_INFO
moduleToImport = env['PATH_INFO'].split('/')[1]
pyFile = homedir + sep + moduleToImport + '.py'
fd = None
try:
fd = win32file.CreateFile(pyFile, GENERIC_READ, FILE_SHARE_DELETE, None, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0)
except Exception as exc1:
fd = None
if fd is not None:
# file exists, get mtime
fd.close()
mt = os.path.getmtime(pyFile)
else:
mt = None
if mt is not None:
h = None
if not pyFile in loadedPages:
# need a new import
if homedir not in sys.path:
sys.path.insert(0, homedir)
h = __import__(moduleToImport, globals(), locals(), [])
# remember
loadedPages[pyFile] = [mt, h]
else:
# retrieve handle to module
h = loadedPages[pyFile][1]
if mt != loadedPages[pyFile][0]:
# need to reload the page
reload(h)
loadedPages[pyFile][0] = mt
if h is not None:
if 'handler' in h.__dict__:
for x in h.handler(env, start_response):
yield x
else:
start_response("400 Bad Request", [('Content-Type', 'text/html')])
else:
start_response("404 Not Found", [('Content-Type', 'text/html')])
yield cr()
yield cr("<html><head><title>Module not found</title>" \
"</head><body>")
yield cr("<h3>404 Not Found</h3>")
yield cr("<h3>No handle</h3></body></html>")
else:
start_response("404 Not Found", [('Content-Type', 'text/html')])
yield cr()
yield cr("<html><head><title>Module not found</title>" \
"</head><body>")
yield cr("<h3>404 Not Found</h3>")
yield cr("<h3>That module (" + moduleToImport + ") was not found.</h3></body></html>")
else:
start_response("500 Internal Server Error", [('Content-Type', 'text/html')])
yield cr()
yield cr("<html><head><title>Server Error</title>" \
"</head><body><h1>Server Error - No ISAPI Found</h1></body></html>")
# def test(environ, start_response):
# '''Simple app as per PEP 333'''
# status = '200 OK'
# start_response(status, [('Content-type', 'text/plain')])
# return ['Hello world from isapi!']
import isapi_wsgi
# The entry point(s) for the ISAPI extension.
def __ExtensionFactory__():
return isapi_wsgi.ISAPISimpleHandler(request_handler)
def PostInstall(params, options):
print "The Extension has been installed"
# Handler for our custom 'status' argument.
def status_handler(options, log, arg):
"Query the status of the ISAPI?"
print "Everything seems to be fine..."
if __name__=='__main__':
# This logic gets invoked when the script is run from the command-line.
# In that case, it installs this module as an ISAPI.
#
# The API provided by isapi_wsgi for this is a bit confusing. There
# is an ISAPIParameters object. Within that object there is a
# VirtualDirs property, which itself is a list of
# VirtualDirParameters objects, one per vdir. Each vdir has a set
# of scriptmaps, usually this set of script maps will be a wildcard
# (*) so that all URLs in the vdir will be served through the ISAPI.
#
# To configure a single vdir to serve Python scripts through an
# ISAPI, create a scriptmap, and stuff it into the
# VirtualDirParameters object. Specify the vdir path and other
# things in the VirtualDirParameters object. Stuff that vdp object
# into a sequence and set it into the ISAPIParameters thing, then
# call the vaguely named "HandleCommandLine" function, passing that
# ISAPIParameters thing.
#
# Clear as mud?
#
# Seriously, this thing could be so much simpler, if it had
# reasonable defaults and a reasonable model, but I guess it will
# work as is.
from isapi.install import *
# Setup the virtual directories -
# To serve from root, set Name="/"
sm = [ ScriptMapParams(Extension="*", Flags=0) ]
vdp = VirtualDirParameters(Name="wsgi", # name of vdir/IIS app
Description = "ISAPI-WSGI Demo",
ScriptMaps = sm,
ScriptMapUpdate = "replace"
)
params = ISAPIParameters(PostInstall = PostInstall)
params.VirtualDirs = [vdp]
cah = {"status": status_handler}
# from isapi.install, part of pywin32
HandleCommandLine(params, custom_arg_handlers = cah)
Using this model, requesting http://foo/wsgi/bar will try loading bar.py from the home directory with the WSGI .dll file. If bar.py cannot be found, you get a 404. If bar.py has been updated since the last run, it reloads. If bar cannot be loaded, you get a 500.
bar.py must export a method called handler, publicly. That method must be a generator. like so:
import time
def handler(env, start_response):
start_response("200 OK", [('Content-Type', 'text/html')])
cr = lambda s='': s + '\n'
yield cr("<html><head><title>Hello world!</title></head><body>")
yield cr("<h1>Bargle Bargle Bargle</h1>")
yield cr("<p>From the handler...</p>")
yield cr("<p>(bargle)</p>")
yield cr("<p>The time is now: " + time.asctime() + " </p>")
yield cr("</body></html>")
__all__ = ['handler']
But as I said, I think GAE is probably a better way to develop Python webapps using Windows.
put this on top of your scrip:
import site
site.addsitedir('path/to/your/site-packages')
the same problem you had, was solved with this two lines

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...

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