Django community: RSS
This page, updated regularly, aggregates Community blog posts from the Django community.
-
Translated text images for lazy programmers
In a previous post about django translations in this blog, I shared how to achieve a quick system that allowed me to manage translations stored in models and served using a template tag. In this post I will explain how to serve images that contain translated text and, hence, a localized image exists for each language. In my case, images are referenced from <img> HTML tags in templates and from CSS files. First of all we must create a basic structure in our img/ and css/ media folders, creating inside a directory for each language code we will use. For example, if we have two languages -- english and spanish -- we would create img/en/, img/es/, css/en/ and css/es/. In the CSS folders, the same files must be initially copied. If we have, for instance, just one style.css file, it must be both in css/en/style.css and css/es/style.css: css/ en/ style.css es/ style.css For the images, we should create the images that will be translated into each language code folder. All CSS files will reference the non-translated images in the same way, but their own file path to the translated image. I'll give an example. Let's say we have one background … -
A common Django/Postgres unicode fail
If you just installed postgres and created a database, Django will probably fail to bring you unicode happiness. The chances are that your site suffers from this error, even if you have not seen it yet. How to spot and fix "DatabaseError: value too long for type character varying"? Read the blog post! -
Where Django programming and Google Analytics meet
We just recently discovered an issue where a programming decision affected the ease (or lack thereof) of establishing goal funnels in Google Analytics. What we also discovered was that it was completely avoidable with a little better communicatioin between our Django programming staff and our analytics staff. As is typical ... -
Sử dụng Amazon SES với Django
Amazon Simple Email Service (Amazon SES) là một giải pháp email dễ dùng và hiệu quả cho các ứng dụng. Tuy Amazon SES đang được phát triển ở giai đoạn beta nhưng nó đã đáp ứng tương đối đầy đủ nhu cầu nhận và gửi mail.Để đăng ký sử dụng Amazon SES chúng ta làm theo các bước hướng dẫn này để xác minh địa chỉ email cần sử dụng. Nếu làm việc trên môi trường Windows chúng ta cần đọc thêm hướng dẫn này nữa. Trên môi trường Ubuntu khi thực hiện quá trình verify email có thể sẽ gặp thông báo lỗi như là "Can't locate XML/LibXML.pm in @INC....". Lỗi này xảy ra khi máy của bạn chưa có thư việc XML của Perl. Để khắc phục bạn cài thêm 2 thư viện của Perl bằng dòng lệnhsudo apt-get install libio-socket-ssl-perlsudo apt-get install libxml-libxml-perlSau khi verify email thành công chúng ta có thể thực hiện gửi mail, nhưng chỉ gửi và nhận với địa chỉ email mà đã được đăng ký, chủ yếu dùng để debug trước khi thực hiện tiếp quá trình đăng ký Production để gửi email đến các địa chỉ khác.Công việc tiếp theo là … -
Filtering querysets in django.contrib.admin forms
I make extensive use of the django admin interface. It is the primary tool for our support team to look at user data for our product, and I have stretched it in many ways to suit my needs. One problem I often come back to is a need to filter querysets in forms and formsets. Specifically, the objects that should be presented to the admin user in a relationship to the currently viewed object should be filtered. In most cases, this is something as simple as making sure the Person and the Units they work at are within the same company. There is a simple bit of boilerplate that can do this. You need to create a custom form, and attach this to the ModelAdmin for the parent object: {% highlight python linenos %} from django.contrib import admin from django import forms from models import Person, Unit class PersonAdminForm(forms.ModelForm): class Meta: model = Person def __init__(self, *args, **kwargs): super(PersonAdminForm, self).__init__(*args, **kwargs) # This is the bit that matters: self.fields['units'].queryset = self.instance.company.units class PersonAdmin(admin.ModelAdmin): form = PersonAdminForm {% endhighlight %} In actuality, it is a little more complicated than this: you need to test if the selected object has a company, … -
Django: Using Caching to Track Online Users
Recently I wanted a simple solution to track whether a user is online on a given Django site. The definition of "online" on a site is kind of ambiguous, so I'll define that a user is considered to be online if they have made any request to the site in the last five minutes. I found that one approach is to use Django's caching framework to track when a user last accessed the site. For example, upon each request, I can have a middleware set the current time as a cache value associated with a given user. This allows us to store some basic information about logged-in user's online state without having to hit the database on each request and easily retrieve it by accessing the cache.My approach below. Comments welcome.In settings.py:# add the middleware that you are about to create to settingsMIDDLEWARE_CLASSES = ( .... 'middleware.activeuser_middleware.ActiveUserMiddleware', ....)# Setup caching per Django docs. In actuality, you'd probably use memcached instead of local memory.CACHES = { 'default': { 'BACKEND': 'django.core.cache.backends.locmem.LocMemCache', 'LOCATION': 'default-cache' }}# Number of seconds of inactivity before a user is marked offlineUSER_ONLINE_TIMEOUT = 300# Number of seconds that we will keep track of inactive users for before # their last … -
Python and OS X Lion
-
Convention Over Configuration: Django Settings
I've been working with Django for over five years. Even though **I don't consider myself as a programmer**, one of the advantages I seem to have over less experienced Django developers is that I've developed (together with <a href="http://www.syneus.fi/" title="Syneus Solutions -- In Finnish">our team</a>) strong conventions on how I work. This makes developing faster and generally more enjoyable. Conventions are a tool for efficient workflow and to help read and understand code by other people better. Like so many tools, conventions too can be taken to extremes to the point when then they become magic (Rails, anyone), which in Python community is <a href="http://www.reddit.com/r/Python/comments/ex54j/seeking_clarification_on_pylonsturbogearspyramid/c1bo1v5">considered a bad practice</a>. The Python community has a name for code that feels right: that kind of code is _pythonic_. Good, pythonic conventions are logical and easy to remember but also explicit. In other words good conventions should make sense when you see them first time. Django has many documented conventions (like that models should live in `models.py` and views in `views.py`) and even <a href="https://docs.djangoproject.com/en/1.3/internals/contributing/#coding-style">coding guidelines</a> but there are many places that could use more stronger or better ones. This article is first in a series of discussing conventions related to Django. My goal … -
Convention Over Configuration: Django Settings
This is a first article in a series about DRY and pythonic conventions for Web development with Django. The goal is to share and discuss common problems in everyday Django development where there is no documentation nor an obvious way of do it. -
How to always exclude specific Django applications from unit testing
Sometimes your Django project will include applications whose unit tests will never pass. In this post, I will explain a quick fix for this, and, probably more usefully, try to explain how and why I developed the code. -
How to always exclude specific Django applications from unit testing
Sometimes your Django project will include applications whose unit tests will never pass. In this post, I will explain a quick fix for this, and, probably more usefully, try to explain how and why I developed the code. -
Disabling South Migrations
It is often handy to disable (either temporarily or permanently) South migrations for an app. “Disable” in this context means preventing an app’s migrations from being executed so that the app is managed via syncdb while in this state. A couple scenarios where this could be useful… -
An alternative RapidSMS router implementation (with Celery!)
We've been using RapidSMS, a Django-powered SMS framework, more and more frequently here at Caktus. It's evolved a lot over the past year-- from being reworked to feel more like a Django app, to merging the rapidsms-core-dev and rapidsms-contrib-apps-dev repositories into a single codebase (no more submodules!), to finally becoming installable via pypi. The "new core" ... -
Python and Django class/hackathon!
The Los Angeles Python community (LA Django and LA PyLadies) is meeting in Santa Monica on July 23rd to teach Django and hack on all things Python on Saturday, July 23rd. The day will start with a Django class based on the official Django tutorial, then turn into a general hackathon, and finish up with lighting talks.Leading the event is noted Pythonista Katharine Jarmul. As Katharine is giving the talk on web scraping at DjangoCon US, I'm hoping we can get her to give a lightning talk on the subject.Learning DjangoSandy Strong will lead the effort to teach people the fundamentals of Django. Besides all things Django and devops, Sandy is presenting the testing talk at DjangoCon US. And if that isn't good enough for you, she won't be alone teaching - there will be a bunch of us developers experienced with Django there to to provide her with support.Even if you already know Django, please come and hang out for the first half! You can either help out others or work on your own project.Hacking Python and DjangoThe second half of the day will be about working on whatever you want. If you are new to Django and want to finish … -
Creantbits un 15 de juliol
Ahir divendres 15 hi hagué una nova edició del creantbits. Aquesta vegada enlloc de que la inscripció es fes en un comentari al blog, ho ferem amb una aplicació creada ad-hoc i que serví per experimentar amb un hosting de Python. El hosting va caure un pic en el procés d'inscripció (després de tot encara està en beta), però la gent d'Eldarion va respondre i en poques hores estava una altra vegada operatiu. L'aplicació en si crec que ha respost bastant bé, tot i estar feta en quatre potades. Ha permés a la gent que s'havia inscrit prest i després no ha pogut venir, fer-ho saber ràpidament i comunicar-ho al següent de la llista d'espera. Tot d'una que tengui una estona més miraré de documentar l'aplicació (que el codi ja hi està) i posar-ho a bitbucket per tal que si hi ha més gent que s'animi entre tots poguem fer un bon programa de gestió d'events. De l'event en sí poca cosa a dir, la sala plena d'amics, gent que ja coneixia personalment i gent que he pogut desvirtualitzar per primera vegada. Però la part important és amics, això fa que parlar en públic sigui molt menys estressant i també … -
Debian init script for virtualenv'd gunicorn_django
I recently moved my projects to gunicorn and needed init scripts. Here's what I'm currently using. I have the gunicorns running behind nginx, so you might want to tweak the IP and PORT settings. It might also be nice to use start-stop-daemon. #! /bin/sh ### BEGIN INIT INFO # Provides: gunicorn-initscript # Required-Start: $remote_fs $syslog # Required-Stop: $remote_fs $syslog # Should-Start: $nginx # Default-Start: 30 2 3 4 5 # Default-Stop: 70 0 1 6 # Short-Description: virtualenv + gunicorn + nginx debian init script # Description: virtualenv + gunicorn + nginx debian init script ### END INIT INFO # Author: Nicolas Kuttler <hidden> # # Please remove the "Author" lines above and replace them # with your own name if you copy and modify this script. # # Enable with update-rc.d gunicorn-example start 30 2 3 4 5 . stop 70 0 1 6 . # (parameters might not be necessary, test) # Do NOT "set -e" PROJECT=/path/to/project/ VIRTUALENV=/path/to/virtualenv PORT=8888 LOGDIR=/var/log/gunicorn/ # PATH should only include /usr/* if it runs after the mountnfs.sh script PATH=/bin:/usr/bin USER=www-data GROUP=www-data IP=127.0.0.1 WORKERS=5 # I am lazy and just call the init script gunicorn-project NAME=`basename $0` DESC=$NAME LOGFILE="$LOGDIR$NAME.log" PIDFILE="$PROJECT$NAME.pid" CMD="gunicorn_django --user=$USER --group=$GROUP --daemon … -
Debian init script for virtualenv'd gunicorn_django
I recently moved my projects to gunicorn and needed init scripts. Here's what I'm currently using. I have the gunicorns running behind nginx, so you might want to tweak the IP and PORT settings. It might also be nice to use start-stop-daemon. #! /bin/sh ### BEGIN INIT INFO # Provides: gunicorn-initscript # Required-Start: $remote_fs $syslog # Required-Stop: $remote_fs $syslog # Should-Start: $nginx # Default-Start: 30 2 3 4 5 # Default-Stop: 70 0 1 6 # Short-Description: virtualenv + gunicorn + nginx debian init script # Description: virtualenv + gunicorn + nginx debian init script ### END INIT INFO # Author: Nicolas Kuttler <hidden> # # Please remove the "Author" lines above and replace them # with your own name if you copy and modify this script. # # Enable with update-rc.d gunicorn-example start 30 2 3 4 5 . stop 70 0 1 6 . # (parameters might not be necessary, test) # Do NOT "set -e" PROJECT=/path/to/project/ VIRTUALENV=/path/to/virtualenv PORT=8888 LOGDIR=/var/log/gunicorn/ # PATH should only include /usr/* if it runs after the mountnfs.sh script PATH=/bin:/usr/bin USER=www-data GROUP=www-data IP=127.0.0.1 WORKERS=5 # I am lazy and just call the init script gunicorn-project NAME=`basename $0` DESC=$NAME LOGFILE="$LOGDIR$NAME.log" PIDFILE="$PROJECT$NAME.pid" CMD="gunicorn_django --user=$USER --group=$GROUP --daemon … -
Debian init script for virtualenv'd gunicorn_django
I recently moved my projects to gunicorn and needed init scripts. Here's what I'm currently using. I have the gunicorns running behind nginx, so you might want to tweak the IP and PORT settings. It might also be nice to use start-stop-daemon. Raw #! /bin/sh ### BEGIN INIT INFO # Provides: gunicorn-initscript # Required-Start: $remote_fs $syslog # Required-Stop: $remote_fs $syslog # Should-Start: $nginx # Default-Start: 30 2 3 4 5 # Default-Stop: 70 0 1 6 # Short-Description: virtualenv + gunicorn + nginx debian init script # Description: virtualenv + gunicorn + nginx debian init script ### END INIT INFO # Author: Nicolas Kuttler <hidden> # # Please remove the "Author" lines above and replace them # with your own name if you copy and modify this script. # # Enable with update-rc.d gunicorn-example start 30 2 3 4 5 . stop 70 0 1 6 . # (parameters might not be necessary, test) # Do NOT "set -e" PROJECT=/path/to/project/ VIRTUALENV=/path/to/virtualenv PORT=8888 LOGDIR=/var/log/gunicorn/ # PATH should only include /usr/* if it runs after the mountnfs.sh script PATH=/bin:/usr/bin USER=www-data GROUP=www-data IP=127.0.0.1 WORKERS=5 # I am lazy and just call the init script gunicorn-project NAME=`basename $0` DESC=$NAME LOGFILE="$LOGDIR$NAME.log" PIDFILE="$PROJECT$NAME.pid" CMD="gunicorn_django --user=$USER --group=$GROUP … -
Debian init script for virtualenv'd gunicorn_django
I recently moved my projects to gunicorn and needed init scripts. Here's what I'm currently using. I have the gunicorns running behind nginx, so you might want to tweak the IP and PORT settings. It might also be nice to use start-stop-daemon. Raw #! /bin/sh ### BEGIN INIT INFO # Provides: gunicorn-initscript # Required-Start: $remote_fs $syslog # Required-Stop: $remote_fs $syslog # Should-Start: $nginx # Default-Start: 30 2 3 4 5 # Default-Stop: 70 0 1 6 # Short-Description: virtualenv + gunicorn + nginx debian init script # Description: virtualenv + gunicorn + nginx debian init script ### END INIT INFO # Author: Nicolas Kuttler <hidden> # # Please remove the "Author" lines above and replace them # with your own name if you copy and modify this script. # # Enable with update-rc.d gunicorn-example start 30 2 3 4 5 . stop 70 0 1 6 . # (parameters might not be necessary, test) # Do NOT "set -e" PROJECT=/path/to/project/ VIRTUALENV=/path/to/virtualenv PORT=8888 LOGDIR=/var/log/gunicorn/ # PATH should only include /usr/* if it runs after the mountnfs.sh script PATH=/bin:/usr/bin USER=www-data GROUP=www-data IP=127.0.0.1 WORKERS=5 # I am lazy and just call the init script gunicorn-project NAME=`basename $0` DESC=$NAME LOGFILE="$LOGDIR$NAME.log" PIDFILE="$PROJECT$NAME.pid" CMD="gunicorn_django --user=$USER --group=$GROUP … -
The Global Django
One thing that annoys me in many US-based software projects is the narrow mindness of the developers who seem to forget that there is life outside of the US, too. Django has been a very international project from the day one, with admin interface translated to 43 languages and the contrib.localflafor full of great localized stuff like validators for Finnish social security number etc. After Adrian’s official announcement of the worldwide Django sprint (that will be held on Friday, Sept. 14, 2007) there has been a steady flow of volunteers adding their names on the wiki page. As I write this, over hundred volunteers from 26 countries have signed up for the event. It’s just amazing. I wish more open source projects would have as great community that Django has. And greetings to everyone who is attending the sprint next Friday — let’s have fun! :) -
Lightning talk: Hacking EuroPython.org (with Django)
I gave a lightning talk yesterday at the EuroPython conference about my little MyEuroPython mashup. The intention of the talk was not to promote the site but to raise a conversation about how to make better conference websites (and especially EuroPython.org). Main points of my presentation were that conferences are about communication and interaction. Current EuroPython.org does not give any tools for that, and it would be great to have something more 2.0 for the site. For example: Simple site structure with good (live)search Registration and personal preferences using OpenID Allow commenting of sessios Provide a personalizable timetable (that is useful for example when using a mobile phone) Free the data; RSS feeds (and possibly other APIs?)from everything Aggregate blog entries, images, links to the main site Good thing was, there was talk about the presentation afterwards, and we actually volunteered for doing the EuroPython.org with Django next year. Hopefully the discussion lives on! » Comment this entry -
Offline Development With Django
Coming to Django from the PHP-world, running a local development server (as opposed to Apache or a full LAMP-machine set up for just testing) and doing real offline development is something that takes a little bit of learning. After two years of active development with Django, I’d like to share some of my learnings. Why Offline? There are many benefits for developing your site someplace other than the same server which powers the site. I’m sure most of us do development this way. Generally speaking offline development could mean any development that doesn’t happen on the production server. The meaning for offline development in this article is more literal: by offline I mean literally offline, that is without [requiring] a connection to the Web. A well configured development environment helps you write better code efficiently — anywhere. On a side note, don’t blame me if you end up coding Django your whole winter vacation at an idyllic remote cottage ;) Best Practices In the same way that Django lets you separate models, templates and views, it also lets you easily separate production and testing environments. Django also offers several tools for local development, such as the built in Web server … -
Being Robust
Writing software that interacts with other peoples code is hard. To be robust, Postel’s Law suggests to be conservative in what you do; be liberal in what you accept from others. What follows is is a good example of what happens if you don’t. When I posted my first Flickr pictures in 2005, Flickr photo_ids were counted in millions. Year later, they were in hundreds of millions. December last year, they topped 2.1 billion, which also happens to be the maximum value of signed integer type in some programming languages. Here are some examples from my own pictures and their photo_ids from Flickr: 6,029,771 March 2005 289,332,856 November 2006 2,165,862,620 December 2007 After reading about someones problems with the 2,1 billion mark, I reviewed my own code. When I first integrated Flickr API to my homemade photo application in early 2006, I was smart enough to use unsigned integers (that would get me as far as 4,294,967,295) as field type for photo_id but not smart enough to read API documentation that explicitly advices to treat photo_id and other IDs as strings, because “format of the IDs can change over time, so relying on the current format may cause you problems … -
State machines for web development
I'm using FSM a lot, both implicitly and explicitly. I like using them in JavaScript, I'd be crazy without them. On my Django backends, FSMs care for everything on the website to be converted, cleaned up and be fine. The moment you understand FSM is a moment of Truth and Enlightment. -
Foreign key to Django CMS page …
… how to make usable drop-downs with Django CMS pages Problem: some times when you create custom applications or plugins for Django CMS you need a property that connects the current item to a page in the CMS. Nothing simple than this – you just add a ForeignKey in your model that points to the [...]
