repoze.debug 0.2

Forensic debugging WSGI middleware

Middleware which can help with in-production forensic debugging. Currently the only middleware in this package is the responselogger middleware, which logs requests and responses to a file for later perusal.

Installation

Install using setuptools, e.g. (within a virtualenv):

$ easy_install repoze.debug

Configuration via Python

Wire up the middleware in your application:

from repoze.debug.responselogger import ResponseLoggingMiddleware
from logging import getLogger
middleware = ResponseLoggingMiddleware(
               app,
               max_bodylen='3KB',
               logger=getLogger('foo')
              )

The configuration options are as follows:

- ``max_bodylen`` should be the size in bytes (optionally followed by
  KB, MB, or GB) of the response body that should be logged.

- ``logger`` is a PEP 282 logger instance (any).

Configuration via Paste

Wire the middleware into a pipeline in your Paste configuration, for example:

[filter:responselogger]
use = egg:repoze.debug#responselogger
filename = %(here)s/response.log
# if max_bodylen is unset or is 0, it means do not limit body logging
# default is 0
max_bodylen = 3KB
# if max_logsize is unset or is 0, it means do not limit logsize; default is
# 100MB
max_logsize = 100MB
# if backup_count is 0, do not rotate the logfile.  Default is 10.
backup_count = 10

...

[pipeline:main]
pipeline = egg:Paste#cgitb
           responselogger
           myapp

The middleware will log response data to filename.

Operation

Once the middleware is in the pipeline, it will log requests and responses to the logger. An example of the log output for a request follows:

--- REQUEST 860724193 at Fri Jun 13 18:40:47 2008 ---
URL: http://localhost:9971/p_/pl
CGI Variables
  ACTUAL_SERVER_PROTOCOL: HTTP/1.1
  AUTH_TYPE: Basic
  HTTP_ACCEPT: */*
  HTTP_ACCEPT_ENCODING: gzip, deflate
  HTTP_ACCEPT_LANGUAGE: en-us
  HTTP_CONNECTION: keep-alive
  HTTP_HOST: localhost:9971
  HTTP_REFERER: http://localhost:9971/manage_menu
  HTTP_USER_AGENT: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_2; en-us) AppleWebKit/525.18 (KHTML, like Gecko) Version/3.1.1 Safari/525.18
  PATH_INFO: /p_/pl
  REMOTE_ADDR: 127.0.0.1
  REMOTE_PORT: 51422
  REQUEST_METHOD: GET
  SERVER_NAME: vitaminf-2.local
  SERVER_PORT: 9971
  SERVER_PROTOCOL: HTTP/1.1
  SERVER_SOFTWARE: CherryPy/3.0.2 WSGI Server
WSGI Variables
  repoze.debug.request_begin: 1213396847.41
  wsgi process: Multithreaded
  repoze.debug.id: 860724193
  application: <paste.httpexceptions.HTTPExceptionHandler object at 0x17a8fd0>
--- end REQUEST 860724193 ---

Each request is tagged with a (random) identifier. A response is also written to the log, and can be matched up to the request that generated it via the identifier. Here’s an example of a response in the log:

--- RESPONSE 860724193 at Fri Jun 13 18:40:47 2008 (0.0083 seconds) ---
Status: 200 OK
Response Headers
  Cache-Control: public,max-age=60
  Content-Length: 872
  Content-Type: image/gif
  Last-Modified: Thu, 06 Mar 2008 17:25:30 GMT
Bodylen: 872
Body:

1?9p?:'~?? ?0a???q?J?(I?|;@@???????@?????!?,H? ?H?`?2t???K.LH?`D?
--- end RESPONSE 860724193 ---

Reporting Bugs / Development Versions

Visit http://bugs.repoze.org to report bugs. Visit http://svn.repoze.org to download development or tagged versions.

0.2 (2008/06/14)

• Add warning if content-length != body length.

0.1 (2008/06/13)

• Initial release.