How to debug/log wsgi python app?

Question

I tried this:

#!/usr/bin/python    

from wsgiref.simple_server import make_server
from cgi import parse_qs, escape
import logging
import os
import sys

html = """
<html>
<body>
   <form method="post" action="parsing_post.wsgi">
      <p>
         Age: <input type="text" name="age">
         </p>
      <p>
         Hobbies:
         <input name="hobbies" type="checkbox" value="software"> Software
         <input name="hobbies" type="checkbox" value="tunning"> Auto Tunning
         </p>
      <p>
         <input type="submit" value="Submit">
         </p>
      </form>
   <p>
      Age: %s<br>
      Hobbies: %s
      </p>
   </body>
</html>
"""

def application(environ, start_response):

   # the environment variable CONTENT_LENGTH may be empty or missing
   try:
      request_body_size = int(environ.get('CONTENT_LENGTH', 0))
   except (ValueError):
      request_body_size = 0

   # When the method is POST the query string will be sent
   # in the HTTP request body which is passed by the WSGI server
   # in the file like wsgi.input environment variable.
   logger = logging.getLogger(__name__)
   request_body = environ['wsgi.input'].read(request_body_size)
   d = parse_qs(request_body)


   age = d.get('age', [''])[0] # Returns the first age value.
   hobbies = d.get('hobbies', []) # Returns a list of hobbies.

   # Always escape user input to avoid script injection
   age = escape(age)
   hobbies = [escape(hobby) for hobby in hobbies]

   response_body = html % (age or 'Empty',
               ', '.join(hobbies or ['No Hobbies']))

   status = '200 OK'

   response_headers = [('Content-Type', 'text/html'),
                  ('Content-Length', str(len(response_body)))]
   start_response(status, response_headers)

   return [response_body]

But i don't know where it logs. I'm trying to display/log the value on webpage or in a file /var/log/apache2/myapp.log

What's the best way to do this?

Any answer will be highly appreciated.

See code.google.com/p/modwsgi/wiki/DebuggingTechniques

Martijn Pieters
– Martijn Pieters

2012-07-03 11:41:47 +00:00
Commented Jul 3, 2012 at 11:41 — Martijn Pieters
– Martijn Pieters, Commented Jul 3, 2012 at 11:41

bruno desthuilliers · Accepted Answer · 2012-07-03 11:34:48Z

7

Note that the above code won't actually produce any log whatsoever since your not calling any of the logger.log() variants - but I guess that's not the point.

If you're running your code with apache/mod_wsgi, the simplest solution is to configure your logger(s) to log to sys.stderr using a StreamHandler (cf http://docs.python.org/howto/logging.html#configuring-logging), and define the error log path, name and level in your apache conf (beware, the default apache behaviour is to only log "error level" message).

answered Jul 3, 2012 at 11:34

bruno desthuilliers

78.3k6 gold badges103 silver badges129 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Martijn Pieters Over a year ago

And code.google.com/p/modwsgi/wiki/DebuggingTechniques tells you how to raise the log level.

Collectives™ on Stack Overflow

How to debug/log wsgi python app?

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related