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Overview
A very brief overview of django-logging.
IntroductionIt is really useful to know what your Django project is doing, especially when debugging. If you're running Django via runserver, then you can simply use print statements and they will appear in the console. If you're running via mod_python, then you can output the print statements to the web server's error log by redirecting to stdout (print >>sys.stdout). While useful, these both have their limitations. Python had a built-in logging system, so django-logging was created to allow it to be easily used within Django projects. What's new
InstallationIt's assumed that you have at least a basic knowledge of Django, Python and Subversion. The source code for django-logging is stored in a Subversion repository, so to start with, you'll need to check out a copy, making sure that you put it somewhere on your PYTHONPATH: svn co http://django-logging.googlecode.com/svn/trunk/djangologging/ djangologging Step 1. Add the django-logging middleware to your Django project's settings file: MIDDLEWARE_CLASSES = (
...
'djangologging.middleware.LoggingMiddleware',
...
)The order of MIDDLEWARE_CLASSES is important: the django-logging middleware must come after any other middleware that encodes the response's content (such as GZipMiddleware). Step 2. The django-logging middleware will only operate if your IP address is in the INTERNAL_IPS setting, so you will have to set this appropriately. If you're working locally, you may need to set this to something like: INTERNAL_IPS = ('127.0.0.1',)Step 3. As an additional security measure, the django-logging middleware will only add its output to HTML pages when:
That's it! (See the Configuration section below for information on the various configurable options.) Usagedjango-logging uses the standard Python logging module, so simply import it and log whatever messages you like. For example: import logging
logging.debug('This is a sample debug message')
logging.info('This is a sample informational message')
logging.warn('This is a sample warning message')
logging.error('This is a sample error message')
logging.critical('This is a sample critical message')When you view a page in your browser, any log messages that were created during the processing of your request will appear at the bottom of the page. One key feature of all this is that because this is using the standard logging framework, you can add other handlers to do other things, such as logging ERROR and CRITICAL level messages to a file. This could be expecially useful on a production server. There are a number of sites which provide some useful information on using the logging module, including: How it worksA custom log handler is created that buffers all messages logged on a per-thread basis. This equates to a per-request basis within Django. After the request has been processed and response generated, the middleware checks if the response is a HTML page (i.e. has a Content-Type header of text/html). If so, it writes the request's log messages into the HTML document. Extra HTTP headers are also added to indicate that the rewritten page should not be cached. Note that unlike the built-in Django debug pages, django-logging does not sanitise any of the content; that is if you log any sensitve information (such as passwords), this will be displayed verbatim in clear text. Configurationdjango-logging should just work "out of the box", but you can configure the following options in your Django settings file:
Output suppressionIf there is a particular view that generates log messages that should not be appended to the page, you can use the suppress_logging_output decorator. For example: from djangologging.decorators import suppress_logging_output
@suppress_logging_output
def some_view(request):
...If you're using AJAX to request a page, you may not wish django-logging to append its output to the response. Most Javascript libraries will add the X-Requested-With: XMLHttpRequest to AJAX requests, so you can use the SuppressLoggingOnAjaxRequestsMiddleware to stop log messages from being outputted. This middleware should be installed after the main logging middleware: MIDDLEWARE_CLASSES = (
...
'djangologging.middleware.LoggingMiddleware',
'djangologging.middleware.SuppressLoggingOnAjaxRequestsMiddleware',
...
)Future FeaturesSome things I'd like to add when I get the time:
FeedbackIf you spot any bugs, have suggestions for improvement or ideas for future features, please use the issue tracker. If you wish to email, my details are on my own site's contact page. |
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Hi
django-logging middleware doesn't work with Django version 0.97-pre-SVN-7698, it doesn't append the html info like it should
I've looked into this and as a result noticed that the documentation of was slightly, but very significantly, wrong. Within MIDDLEWARE_CLASSES, the django-logging middleware must come after any other middleware that encodes the response's content (such as GZipMiddleware).
I have updated the documentation (r23) to correct this.
Can you try again in your environment? If you are still experiencing problems, please raise a new issue with as much detail as you can.
It is working now!, thanks
Is there any way to use django-logging to log messages to a file (or e-mail) on a production server? Thanks!
Doh. I just found the part of the docs above that say exactly what I'm looking for. Nevermind.
You and the django-debug-bar should join projects! It would be really useful to have the log output as a panel of the debug-bar.
Thanks for this, it's very useful.
RJ Ryan
you guys need to advertise more, i got halfway into making a whole template tag/filter library to output queries and such before i found this :). Nice job, works great with django 1.0. One comment, you should add that you have to explicitly define INTERNAL_IPS in settings, took me a few minutes to figure out that it does not have a default value within django.
I found that with INTERNAL_IPS set to '127.0.0.1' that logging was always enabled whether or not DEBUG was true or LOGGING_OUTPUT_ENABLED was false.
Absolutely amazing job, guys. For folks who need to use apache for a development server, this is by far the best way to work. Using 'tail -f apache.log' and figuring out how to print to the apache log is a fairly miserable experience compared to this. Again, thank you so much.
thanks for making such an excellent tool!
Does not work if the encoding of the source file is # -- coding: utf8 --
Thanks a lot!
Thanks for this, love it!
'lo, do I have to do anything special to get this working for the admin interface? got it all setup as required but I only ever see "No log entries" underneath the "Request Log" bar at the bottom of the page :(
I'm using Django 1.0-final-SVN-9017 and I have a simple view that merely loads a template and the RequestContext?(request) before I return the render_to_response I am calling import logging and then logging.debug('test') and when I load the page it outputs this error:
IOError at /my/views/url/path/ could not get source code
Any idea what's happening?
I've branched the code into bitbucket: http://bitbucket.org/refack/djangologging/ Adding several bug fixes (such as cookie handling & the infamous IOError), and also some new features, like request.session content logging, and Traceback.