Web.py on dotcloud with wsgi

Question

I'm trying to deploy my web.py app on dotcloud, but can't figure out how to do it.

I went through this tutorial fine: http://docs.dotcloud.com/static/tutorials/firststeps/

And then I looked at http://docs.dotcloud.com/static/components/python/ ...

The python service can host any python web application compatible with the WSGI standard.

That includes all modern Python web frameworks: Django, Pylons, web.py, web2py, etc.

...

python runs with Nginx + uWSGI, managed by supervisord. Static assets are served directly by Nginx, for greater performance.

...

DotCloud relies on well-established tools and conventions to build your app. It should be trivial to adapt any application to run on DotCloud.

...

When deploying your app, DotCloud looks for a file called wsgi.py. Make sure to create that file at the root of your application directory.

---

Googling "web.py wsgi" leads to http://webpy.org/install which has a pretty bewildering array of instructions. I tried a number of suggestions on the page, but couldn't get anything to work.

The most promising prospect seemed to be creating a file called wsgi.py like so:

import web

urls = (
  '/(.*)', 'hello'
)

class hello:    
  def GET(self, name):
    if not name: 
      name = 'World'
    return 'Hello, ' + name + '!'

app = web.application(urls, globals(), autoreload=False)
application = app.wsgifunc()

I also created an empty __init__.py next to it.

Then I did:

dotcloud create jca_hello.py
dotcloud deploy -t python jca_hello.www
dotcloud push jca_hello.www .

But now when I go to http://www.jca_hello.dotcloud.com/ all I see is:

uWSGI Error

wsgi application not found

Any ideas?

Answer 1

I am fellow user of web.py and I work at DotCloud by the way :-)

We use uWSGI to run your WSGI application. The point is that uWSGI is looking for a variable named "application".

Here is what I usually do:

app = web.application(urls, globals())

if __name__ == '__main__':
    app.run()
else:
    web.config.debug = False
    application = app.wsgifunc()

So you can both continue to use your app on your local machine:

$ python ./wsgi.py

And push it on production (on DotCloud of course ;) with debug mode disabled.

Here is your wsgi.py file corrected:

import web

urls = (
  '/(.*)', 'Hello'
)

class Hello(object):

    def GET(self, name):
        if not name:
            name = 'World'
        return 'Hello, ' + name + '!'

app = web.application(urls, globals())

if __name__ == '__main__':
    app.run()
else:
    web.config.debug = False
    application = app.wsgifunc()

Beware of correctly having your wsgi.py in your approot.

Also make sure that you have a file named "requirements.txt" in your approot containing:

web.py

In the meantime, do not hesitate to contact the DotCloud support if you have any problem with your deployments.