Over the past 6 years, I've built a lot of things with Django. It has treated me very well, and I have very much enjoyed seeing it progress. I got into Django when I helped the company I was working for transition away from a homegrown PHP framework toward something more reliable and flexible. It was very exciting to learn more about Django at a time when the ecosystem was very young.

When I started with Django, there weren't a lot of pluggable apps to fill the void for things like blogs, event calendars, and other useful utilities for the kinds of sites I was building. That has changed quite a bit since then. The ecosystem has evolved and progressed like mad, and it's wonderful. We have so many choices for simple things to very complex things. It's amazing!

Unfortunately, during this whole time period, my development efforts have shifted from creating my own open source projects to share with the world toward more proprietary solutions for my employers. If it's not obvious to you from my blog activity in recent years, I've become very busy with family life and work. I have very little time to give my open source projects the attention they deserve.

For at least 4 years, I've been telling myself that I'd have/make time to revamp all of my projects. To make them usable with what Django is today instead of what it was when I built the projects. Yeah, this time has never showed up. Take a look at the last time I wrote a blog article!

I have decided to disown pretty much all of my open source Django projects. I've basically done this with one or two of the more popular projects already--let someone else take the reigns while I lurk in the background and occasionally comment on an issue here or there. I truly appreciate those who have taken the initiative here. But there are still plenty of projects that people may find useful that need some attention. I'm putting it up to the community to take these projects over if you find them useful so they can get the love and attention they need.

Here is a list of Django projects that anyone is free to assume responsibility for. Most of them are silly and mostly useless now. Some are unpleasant to look at and could use an entire rewrite.

• django-articles - Blogging engine, which I wrote for my own site many years ago. This one could probably use a full rewrite. [already maintained by John Leith].
• django-tracking - Visitor tracking to see what page a user is on and their general location based on IP. Update 2015-07-28: Adopted by bashu.
• django-axes - Track failed login attempts and ban users. This one is already pretty much owned by aclark4life
• django-reploc - Designed to show representative/retailer locations. I only used it on one site, but it was designed to be generic.
• django-smileys - To easily replace things like :) and B-) with emoticons or whatever. Pretty lame. Update 2015-07-28: Adopted by bashu.
• django-pendulum - A very basic time-tracking app. I believe this has already been forked and used for some more interesting commercial projects.
• django-bibliophile - A way to let your visitors know what you're reading.
• django-watermark - Some utilities to add watermarks to images. Update 2015-07-28: Adopted by bashu.
• Any other Django-related project you see at https://github.com/codekoala?tab=repositories or https://bitbucket.org/codekoala/

The fact that I'm giving up these projects does not mean I'm giving up on Django. On the contrary, I'm still using it quite heavily. I'm just doing it in such a way that I can't necessarily post my work for everyone to use. I honestly don't expect much of this disowning effort, since the projects are mostly stale and incompatible with recent versions of Django. But please let me know if you do want to take over one of my projects and care for it.

The activity on my latest blog post has been tremendous! I never expected that much activity within an hour or two of posting the article.

The aim of this article is to provide an alternative solution to my weighted sort when you're after increased performance. It might just be useful to those who came here in search of a way to do weighted sorting in Python. I need to give a shout out to Jeremy Brown for suggesting this solution. He's so awesome :P

While the example I posted in my previous article addressed my needs just fine, it is definitely not the fastest option. A better solution would be to completely remove the special IDs from the object list altogether and just place them in front of the list:

import itertools
import random

object_ids = [random.randint(0, 100) for i in range(20)]
special_ids = [random.choice(object_ids) for i in range(5)]

not_special_ids = (i for i in object_ids if i not in special_ids)
for i in itertools.chain(special_ids, not_special_ids):
    # do stuff with each ID
    pass

This solution is quite different from my weighted sort, as there's no sorting going on at all, just a simple generator and using itertools to chain two collections together.

Here's a way you can benchmark see which solution is faster:

from copy import copy
import cProfile
import itertools
import random

object_ids = [random.randint(0, 100) for i in range(20)]
special_ids = [random.choice(object_ids) for i in range(5)]

ITERATIONS = 1000000

def sorting():
    for i in xrange(ITERATIONS):
        l = copy(object_ids)
        l.sort(key=lambda i: int(i in special_ids) * -2 + 1)
        for i in l:
            pass

def chaining():
    for i in xrange(ITERATIONS):
        l = (i for i in object_ids if i not in special_ids)
        for i in itertools.chain(special_ids, l):
            pass

cProfile.run('sorting()')
cProfile.run('chaining()')

Sample output on my box is:

$ python weighted_sort.py
         24000003 function calls in 18.411 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000   18.411   18.411 <string>:1(<module>)
  1000000    0.580    0.000    0.580    0.000 copy.py:112(_copy_with_constructor)
  1000000    0.791    0.000    1.510    0.000 copy.py:65(copy)
        1    1.397    1.397   18.411   18.411 weighted_sort.py:11(sorting)
 20000000    8.907    0.000    8.907    0.000 weighted_sort.py:14(<lambda>)
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
  1000000    0.139    0.000    0.139    0.000 {method 'get' of 'dict' objects}
  1000000    6.597    0.000   15.503    0.000 {method 'sort' of 'list' objects}


         16000003 function calls in 7.381 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000    7.381    7.381 <string>:1(<module>)
        1    2.744    2.744    7.381    7.381 weighted_sort.py:18(chaining)
 16000000    4.636    0.000    4.636    0.000 weighted_sort.py:20(<genexpr>)
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}

So, you can see that the chaining solution is easily twice as fast as the sorting solution over 1 million iterations. Both of these solutions work perfectly well for my purposes, and I will probably end up switching to the chaining solution sometime in the future.

EDIT After reading lqc's comment on my previous article, I've decided to update this one with more appropriate benchmarks. The information that lqc has shared makes the speed of these solutions much closer.

Here's my updated test script:

$ python weighted_sort.py
         4000003 function calls in 8.437 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000    8.437    8.437 <string>:1(<module>)
  1000000    0.558    0.000    0.558    0.000 copy.py:112(_copy_with_constructor)
  1000000    0.741    0.000    1.431    0.000 copy.py:65(copy)
        1    1.319    1.319    8.437    8.437 weighted_sort.py:11(sorting)
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
  1000000    0.133    0.000    0.133    0.000 {method 'get' of 'dict' objects}
  1000000    5.688    0.000    5.688    0.000 {method 'sort' of 'list' objects}


         17000003 function calls in 7.545 CPU seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000    7.545    7.545 <string>:1(<module>)
        1    2.818    2.818    7.545    7.545 weighted_sort.py:18(chaining)
 17000000    4.726    0.000    4.726    0.000 weighted_sort.py:20(<genexpr>)
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}

So if you only gain a second over 1 million iterations, I think I prefer the sort(key=special_ids.__contains__) solution! I hope these two articles will help you get started on your adventures with handling special objects before others!

I've been working on some neat changes to django-articles recently, and I've just released version 2.1.1. The most noticeable feature in this release is Auto-Tagging. Since I feel like I've described the feature fairly well in the README, I'll just copy/paste that section here.

The auto-tagging feature allows you to easily apply any of your current tags to your articles. When you save an Article object with auto-tagging enabled for that article, django-articles will go through each of your existing tags to see if the entire word appears anywhere in your article's content. If a match is found, that tag will be added to the article.

For example, if you have tags "test" and "art", and you wrote a new auto-tagged Article with the text:

This is a test article.

django-articles would automatically apply the "test" tag to this article, but not the "art" tag. It will only apply the "art" tag automatically when the actual word "art" appears in the content.

Auto-tagging does not remove any tags that are already assigned to an article. This means that you can still add tags the good, old-fashioned way in the Django Admin without losing them. Auto-tagging will only add to an article's existing tags (if needed).

Auto-tagging is enabled for all articles by default. If you want to disable it by default (and enable it on a per-article basis), set ARTICLES_AUTO_TAG to False in your settings.py file.

Auto-Tagging does not attempt to produce any keywords that magically represent the content of your articles. Only existing tags are used!!

I sure had fun programming this little feature. I know it will be particularly useful for my own site.

Another item I'd like to mention about this release: I've finally started using South migrations in this app. This is a move I've been planning to make for quite some time now.

Head on over to http://bitbucket.org/codekoala/django-articles or use pip install -U django-articles (or easy_install django-articles if you must)! Enjoy!

I've spent a little more time lately adding new features to django-articles. There are two major additions in the latest release (2.0.0-pre2).

• Article attachments
• Article statuses

That's right folks! You can finally attach files to your articles. This includes attachments to emails that you send, if you have the articles from email feature properly configured. To prove it, I'm going to attach a file to this article (which I'm posting via email).

Next, I've decided that it's worth allowing the user to specify different statuses for their articles. One of the neat things about this feature is that if you are a super user, you're logged in, and you save an article with a status that is designated as "non-live", you will still be able to see it on the site. This is a way for users to preview their work before making it live. Out of the box, there are only two statuses: draft and finished. You're free to add more statuses if you feel so inclined (they're in the database, not hardcoded).

The article status is still separate from the "is_active" flag when saving an article. Any article that is marked as inactive will not appear on the site regardless of the article's "status".

On a slightly less impressive note (although still important), this release includes some basic unit tests. Most of the tests currently revolve around article statuses and making sure that the appropriate articles appear on the site.

Some of you who prefer to use git for your version control needs and were following the django-articles mirror on GitHub may have noticed some strange activity recently. I noticed today that the GitHub mirror was out of sync with the other mirrors, and I took a bit of time to investigate the problem.

I thought, for some reason, that I might be able to quickly and easily bring it back into sync if I just deleted the repo, recreated it, and pushed my changes to it. That didn't work. This means that all of you who were once following the project there are no longer following it, and I only realized that side effect after I had clicked the delete button. I apologize for this inconvenience.

In the end, it turned out that I had some things misconfigured with git on my box. I have resolved the problems and have brought the mirror back into sync. Please let me know if you run into any problems with it!

One of the features that I really like about sites like posterous and tumblr is that they allow you to send email to a special email address and have it be posted as a blog article. This is a feature I've been planning to implement in django-articles pretty much since its inception way back when. I finally got around to working on it.

The latest release of django-articles allows you to configure a mailbox, either IMAP4 or POP3, to periodically check for new emails. A new management command check_for_articles_from_email can be used to process the messages found in the special mailbox. If any emails are found, they will be fetched, parsed, and posted based on your configuration values. Only articles whose sender matches an active user in your Django site will be turned into articles. You can configure the command to mark such articles from email as "inactive" so they don't appear on the site without moderation. The default behavior, actually, is to mark the articles inactive--you must explicitly configure django-articles to automatically mark the articles as active if you want this behavior.

One of the biggest things that you should keep in mind with this new feature, though, is that it does not currently take your attachments into account. In time I plan on implementing this functionality. For now, only the plain text content of your email will be posted. Please see the project's README for more information about this new feature.

Please keep in mind that this is brand new functionality and it's not been very well tested in a wide variety of situations. Right now, it's in the "it works for me" stage. If you find problems with it, please create a ticket or update any similar existing tickets using the ticket tracker on bitbucket.org.

You can install or update django-articles using the following utilities:

• pip install -U django-articles
• easy_install -U django-articles
• hg clone http://bitbucket.org/codekoala/django-articles/ or just hg pull -u if you have already cloned it
• git clone git://github.com/codekoala/django-articles.git

Enjoy!

P.S. This article was posted via email

I've recently been working on some performance enhancements on my site. Apparently some of my latest articles are a little too popular for my shared hosting plan. The surge of traffic to my site took down several sites on the same server as my own.

My response to the fiasco was to, among other things, implement caching on my site. It seems like the caching has helped a lot. I've noticed that my RSS feeds are hit almost as hard as real articles on my site, and I noticed that they weren't being cached the way I had expected. I tried a couple of things that I thought would work, but nothing seemed to do the trick.

After doing some brief research into the idea of caching my RSS feeds using Django's built-in caching mechanisms, I came up empty. It occurred to me to implement caching in the feed classes themselves. I tried something like this:

from django.contrib.syndication.feeds import Feed
from django.core.cache import cache
from articles.models import Article

class LatestEntries(Feed):
    ...

    def items(self):
        articles = cache.get('latest_articles')

        if articles is None:
            articles = Article.objects.active().order_by('-publish_date')[:10]
            cache.set('latest_articles', articles)

        return articles

    ...

This code doesn't work! When I would try to retrieve one of my RSS feeds with such "caching" in place, I got the following traceback:

Traceback (most recent call last):

  File "/home/wheaties/dev/django/core/servers/basehttp.py", line 280, in run
    self.result = application(self.environ, self.start_response)

  File "/home/wheaties/dev/django/core/servers/basehttp.py", line 674, in __call__
    return self.application(environ, start_response)

  File "/home/wheaties/dev/django/core/handlers/wsgi.py", line 241, in __call__
    response = self.get_response(request)

  File "/home/wheaties/dev/django/core/handlers/base.py", line 143, in get_response
    return self.handle_uncaught_exception(request, resolver, exc_info)

  File "/home/wheaties/dev/django/core/handlers/base.py", line 101, in get_response
    response = callback(request, *callback_args, **callback_kwargs)

  File "/home/wheaties/dev/django/utils/decorators.py", line 36, in __call__
    return self.decorator(self.func)(*args, **kwargs)

  File "/home/wheaties/dev/django/utils/decorators.py", line 86, in _wrapped_view
    response = view_func(request, *args, **kwargs)

  File "/home/wheaties/dev/django/contrib/syndication/views.py", line 215, in feed
    feedgen = f(slug, request).get_feed(param)

  File "/home/wheaties/dev/django/contrib/syndication/feeds.py", line 37, in get_feed
    return super(Feed, self).get_feed(obj, self.request)

  File "/home/wheaties/dev/django/contrib/syndication/views.py", line 134, in get_feed
    for item in self.__get_dynamic_attr('items', obj):

  File "/home/wheaties/dev/django/contrib/syndication/views.py", line 69, in __get_dynamic_attr
    return attr()

  File "/home/wheaties/dev/articles/feeds.py", line 22, in items
    cache.set(key, articles)

  File "/home/wheaties/dev/django/core/cache/backends/filebased.py", line 72, in set
    pickle.dump(value, f, pickle.HIGHEST_PROTOCOL)

PicklingError: Can't pickle <class 'django.utils.functional.__proxy__'>: attribute lookup django.utils.functional.__proxy__ failed

This error took me by surprise. I didn't expect anything like this. I tried a few things to get around it, but then I actually stopped to consider what was happening to cause such an error. My Article objects are definitely serializable, which is why the error didn't make sense.

Then it hit me: the object I was actually attempting to cache was a QuerySet, not a list or tuple of Article objects. Changing the code to wrap the Article.objects.active() call with list().

from django.contrib.syndication.feeds import Feed
from django.core.cache import cache
from articles.models import Article

class LatestEntries(Feed):
    ...

    def items(self):
        articles = cache.get('latest_articles')

        if articles is None:
            articles = list(Article.objects.active().order_by('-publish_date')[:10])
            cache.set('latest_articles', articles)

        return articles

    ...

And that one worked. I would prefer to cache the actual XML version of the RSS feed, but I will settle with a few hundred fewer hits to my database each day by caching the list of articles. If anyone has better suggestions, I'd love to hear about them. Until then, I hope my experience will help others out there who are in danger of taking down other sites on their shared hosting service!

One of the tools I find myself using more and more each day is the amazing grep. It helps me narrow down the list of potential problem children in my code. Sometimes it can even tell me exactly where I need to look if my parameters are specific enough.

For example, the other day, I had a problem where some Python code was attempting to call isdigit() on an integer, when the variable was supposed to be a string. I could have scoured the code manually for all occurrences of the word "isdigit", or I could have used a "search in files" sort of feature in any useful text editor. There are likely other options too. However, I opted to use grep to find what I was looking for.

In the process of fixing this bug, I learned that grep offers the option of displaying a few lines of context around your matching text. There are a few ways you can tell grep to give you some context:

• -A NUM, --after-context=NUM

  Print NUM lines of trailing context after matching lines. Places a line containing -- between contiguous groups of matches.

• -B NUM, --before-context=NUM

  Print NUM lines of leading context before matching lines. Places a line containing -- between contiguous groups of matches.

• -C NUM, --context=NUM

  Print NUM lines of output context. Places a line containing -- between contiguous groups of matches.

I thought this was so useful that I wrote a small shell script to wrap up my common options for grepping--recursive search, display line numbers, and (now) showing some context. Eventually I got around to cleaning up the output by dirtying up the script. Cleaning up the output involved only displaying a matching filename one time, with the line numbers for the context and matching lines below it. I also thought it would be easier to find matching lines if I could colorize the matched text. Here's my script as of noon today.

#!/bin/bash
# Recursively greps for some text in files in the current directory with some
# context lines.

GREEN=`echo -e '\033[41;30;1m'`
NORMAL=`echo -e '\033[0m'`
FIND=$1
grep --exclude=*.svn* --exclude=*.swp -rnC 5 "$FIND" * | \
    awk '{split($1, a, "-"); split(a[1], b, ":"); \
    if (b[1] != file) { file=b[1]; print file; } \
    sub(file, "", $0); print $0; }' | \
    sed -e "s/$FIND/$GREEN&$NORMAL/g;s/^[-\:]//g"

I'm sure there are ways to make this more elegant, but I'm sure happy with it. This little dandy assisted me just this morning in helping a friend resolve some Django bugs!

Here's a screenshot:

Along with my recent adventures with Fedora 11, I decided to force myself to become more proficient with VIM. For those of you who do not know, VIM is based on perhaps one of the oldest surviving text editors around today. There are often religious-grade battles between those who believe in VIM and those who believe in Emacs, another long-surviving text editor. I'm not trying to get into any debates about which is better, and I'm not interested in why I should not be using VIM. If you still feel like I need to be set straight, please use the contact me form instead of the comments section.

Anyway, most people who use these editors fall into 1 of 3 categories (there are probably more categories actually):

1. They're familiar with it enough to get the job done, but they're not exactly proficient. Therefore, they don't care about evangelizing the editor.
2. They're proficient with the editor, but they're afraid of the politics involved in religious wars relating to text editors, so they don't evangelize.
3. They're proficient with the editor and feel that the whole world would be better off if everyone used their preferred text editor. As such, they cannot shut up about the dang thing and drive all of their friends, coworkers, and acquaintances mad.

A few of you will probably agree with what I'm about to say. I fear I have transitioned from stage 1 to stage 3 fairly rapidly. I can't stop talking about VIM all of the sudden! You'd think it's the next best thing after sliced bread the way I've been blabbering about it. And here I am, writing an article about it. Hah.

Ever since I first started using Linux, I have been using vi to handle most of my text editing when I was in a terminal. I knew enough to get around. Basic things like navigation and inserting text were pretty much all I knew how to do. I dabbled with a tutorial here and there, but it wasn't long before the things I learned were lost, since I usually preferred a graphical text editor over VIM.

My recent experimentation with VIM has proved to be very fruitful, if I do say so myself. I am no longer tied down to some editor that is slow and bulky, I don't have much to worry about when I switch computers (chances are that VIM is on any computer I use regularly), and I don't even need to be sitting at the computer I'm using VIM on! In fact, today I was doing most of my work over an SSH session to my netbook. I felt more productive today than I have in a very long time.

It's been a long time since I've enjoyed using a mouse to perform basic tasks on my computer. Using VIM allows me to rid myself of the mouse entirely for my text editing tasks, and I don't feel at all limited in my capabilities. Things that used to be quite sketchy operations using my favorite graphical editors end up being very simple with VIM.

I also love the obscurity favor of it all.

Examples
========

<a href="http://www.somelong.com/that/I/want/to/change/">Link Text</a>

:s/something/lambda (a,b,c): \0(a,b,c)/g

:.,.+9 s/something/lambda (a,b,c): \0(a,b,c)/g

Alrighty folks. Good night's rest? Check. Need to get work done? Check. Today's adventure will be about getting my computer set up for the regular development tasks that I need to do every day for my work and hobbies.

Installing/Configuring The Tools

As I previously mentioned, I prefer to use things that work well without getting in my way. When talking about text editors, VIM is just fine for me, and VIM 7.2.148 is already installed on my Fedora 11. One less thing to install.

Next up comes the installation of all of the goods for Firefox. It turns out that Fedora comes with Firefox 3.5 Beta 4--a bold move. I hope my extensions all work! The extensions I will be installing right now include:

• AdBlock Plus: get rid of pesky ads that slow down my computer
• Firebug: an amazing tool when debugging Web pages
• Web Developer: has some niceties that Firebug doesn't come with
• Screengrab: fantastic for taking screenshots of full Web pages
• 2Zeus: my own little extension that allows me to quickly get short URLs a la tinyurl.com and is.gd

When I plugged in my external 1TB Seagate hard drive, I got a delicious Fatal Error message:

All appears to be in order, however, as I have access to all of the partitions on the external drive.

Next I want to install Opera. It appears that the place to look is Applications > System > Software Management in the KDE menu. Let's see what we have. Searching for Opera in the only obvious search box sent my computer into a crazy "let me do something without telling you" cycle. I have no idea what's really going on, but my processor has been maxed out for the past 3 minutes and my network has been working a little here and there. Can it really be that difficult to find a simple package? Oh! It finished! It took 6 minutes and 54 seconds to find nothing. Excellent. Let me look somewhere else.

Awesome. My computer is non-responsive. The hard drive is still working, but my GUI is doing nothing. I love it. Attempts to drop back to a trusty console using Control, Alt, and F1-F6 rendered no results. I wonder if I can SSH in from here... I sure can! Fantastic. Let's see what's happening.

It appears that X is taking up 90% of my processing power, but my computer is still not responding to any of my input. Dang it! Now my SSH session isn't working. Looks like the only option I have now is to do a hard reset. Joy of joys. Thank you for this opportunity, Fedora. Last time I did a hard reset, I was in Windows and it trashed my 1TB external.

So far rebooting seems to be going well. I wonder if my network will be setup properly still... Fantastic! It works! Wireless is still not available though. I can live without that for the time being.

Back in the Software Management utility, searching for Opera again proved to work much more quickly, but I didn't get any results. I suppose I'll just go download it from their site. The download for Opera 10 beta 1 is a mere 7.2MB, and it looks like it will open in the same Software Management utility that I've been dinking around in.

When I downloaded the Opera package, I asked it to open directly in the default program, KPackageKit. That doesn't seem to be working in the least, so I am going to try to just save it to my home directory and install it some other way. Sorry guys and gals, I ended up just dropping back to a terminal to run rpm -Uvh opera-10.00-b1.gcc4-shared-qt3.x86_64.rpm and that seemed to work fine. Opera appeared in my KDE menu, and it runs well now.

Next up is Pidgin. Pidgin 2.5.5 is installed by default, and getting it up and running was as trivial as ever.

Now to test Flash... YouTube, here I come!! Beh, Flash is not installed by default, and it's also not in the Software Management tool. What use is that thing?! Maybe if I apply all of the updates in the "Software Updates" section it will feel more useful... Here it goes.

Cool. System is unresponsive again. Let's see if I can reboot from here. Nope! Thank you, Fedora, for making me hard reset my system more in 2 hours than I have had to in YEARS. Yeah, thanks buddy.

10:50 AM So the software updates continue to not work. It appears that a ypbind package is the culprit which is causing everything to hang... I disabled it and tried to install the software updates again.

10:53 AM GUI is non-responsive again. Yay.

10:56 AM Third hard reset in 3 hours. Maybe I will have to modify my original parameters and try GNOME to see if that makes the computer usable for more than an hour at a time.

11:00 AM That's it! I'm getting rid of KDE 4... sorry folks, GNOME is my only hope of getting work done. Second clean shutdown out of 5 since the installation completed last night.