Django community: RSS
This page, updated regularly, aggregates Community blog posts from the Django community.
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Choosing an API framework for Django
First off, out of the box, Django lets you construct API responses with a little work. All you need to do is something like this: # Copied from https://docs.djangoproject.com/en/1.4/topics/class-based-views/#more-than-just-html from django import http from django.utils import simplejson as json class JSONResponseMixin(object): def render_to_response(self, context): "Returns a JSON response containing 'context' as payload" return self.get_json_response(self.convert_context_to_json(context)) def get_json_response(self, content, **httpresponse_kwargs): "Construct an `HttpResponse` object." return http.HttpResponse(content, content_type='application/json', **httpresponse_kwargs) def convert_context_to_json(self, context): "Convert the context dictionary into a JSON object" # Note: This is *EXTREMELY* naive; in reality, you'll need # to do much more complex handling to ensure that arbitrary # objects -- such as Django model instances or querysets # -- can be serialized as JSON. return json.dumps(context) Once you get that mixin, use it in your views like so: # modified from djangoproject.com sample code from django.utils import simplejson as json class JSONDetailView(JSONResponseMixin, MyCustomUserView): def convert_context_to_json(self, context): context['objects'] = User.objects.values('first_name','last_name','is_active') return json.dumps(context) This works pretty well in a number of simple cases, but doing things like pagination, posting of data, metadata, API discovery, and other important things ends up being a bit more work. This is where the resource oriented API frameworks come in. What makes a decent API Framework? … -
New pages available
We added the Zurich page to give you some more details about how to get in, how to get to our locations and how you get around in Zurich.We will soon add even more information about where to go in Zurich to get food and drinks and other useful information. In the meantime, if you have any questions or problems, please don't hesitate to contact us via Twitter or email.See you soon in Zurich! -
Django Requirements for a project
Today I'm starting a new project. I'm working as fast as I can and hope to launch on Friday. What are my package dependencies? Django==1.4 Unlike my last quick project which was Flask, this effort really falls into Django's sweet spot. I need sessions, forms, templates, and models to do things in an ideal Django pattern. psycopg2==2.4.5 I need transactions and hard-type validation in the database, which means PostgreSQL. If I didn't need transactions or the hard-type validation I would consider MongoDB instead. django-debug-toolbar==0.9.4 Because not using this tool is insane. django-extensions==0.8 Because amongst other things this library gives you, I never want to write my own TimeStampedModel ever again. :-) South==0.7.5 Django gives you the freedom to migrate data in the way you want. The way I want to do it is via South. django-registration==0.8.0 Normally django-social-auth is my go-to tool for registration, but in this case I need simple username/password registration. This is a very solid tool, but you do have to make your own templates or find someone's fork that has a copy of templates that match. django-floppyforms==0.4.7 An excellent tool for making your forms HTML5-ish out of the box. django-crispy-forms==1.1.3 The child of my own django-uni-forms, … -
Django Requirements for a project
Today I'm starting a new project. I'm working as fast as I can and hope to launch on Friday. What are my package dependencies? Django==1.4 Unlike my last quick project which was Flask, this effort really falls into Django's sweet spot. I need sessions, forms, templates, and models to do things in an ideal Django pattern. psycopg2==2.4.5 I need transactions and hard-type validation in the database, which means PostgreSQL. If I didn't need transactions or the hard-type validation I would consider MongoDB instead. django-debug-toolbar==0.9.4 Because not using this tool is insane. django-extensions==0.8 Because amongst other things this library gives you, I never want to write my own TimeStampedModel ever again. :-) South==0.7.5 Django gives you the freedom to migrate data in the way you want. The way I want to do it is via South. django-registration==0.8.0 Normally django-social-auth is my go-to tool for registration, but in this case I need simple username/password registration. This is a very solid tool, but you do have to make your own templates or find someone's fork that has a copy of templates that match. Update 2013/12/17: django-registration is no longer maintained and doesn't entirely work with modern Django's new user model system. Use django-allauth … -
Travis, give me my data back!
Inspired from this blog post about "Using Travis-CI With Python and Django" I started playing around to make this recipe fit my expectation from a CI enviroment. Running tests is the bare bottom of the whole thing. Email notifications and the handy badge to display in the project webpage are ok, but if you want to get somewhere metrics and coverage reports are the key to get the most out of the -
Don’t Deploy Broken Code
It’s been rather quiet around here lately, and that’s mainly due to the fact that I have a new job. I’m working as a Django application developer for a company based in Leicester. My job involves taking care of pretty much all the web-related technologies I have blogged about previously, and it challenges me every day. Since I started in February, I have put into place the software and processes I described in my 3-part series about Django in Production. In this post, though, I’d like to describe an extra nifty little trick I added to the deployment process: checking the project’s build status in Jenkins before allowing a deploy to continue. By performing this check before every deploy, we can reduce the risk that potentially broken code ever touches the production environment. Of course, its effectiveness is very much reliant on the quality and coverage of the unit tests but, as they say, every little helps! <!–more–> As I describe in Django in Production: Part 3, Fabric makes a great tool for automatic deployments (though there is an argument for not using this process, excellently described by Hynek Schlawack). To help reduce the risk of making an embarrassing mistake, … -
Distributing Work in Python Without Celery
We've been migrating a lot of data to various places lately at DISQUS. These generally have been things like running consistancy checks on our PostgreSQL shards, or creating a new system which requires a certain form of denormalized data. It usually involves iterating through the results of an en... -
Distributing Work in Python Without Celery
We've been migrating a lot of data to various places lately at DISQUS. These generally have been things like running consistancy checks on our PostgreSQL shards, or creating a new system which requires a certain form of denormalized data. It usually involves iterating through the results of an en... -
"Day against DRM": pragmatic programmer books are always DRM free
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Distributing Work in Python Without Celery
We’ve been migrating a lot of data to various places lately at DISQUS. These generally have been things like running consistancy checks on our PostgreSQL shards, or creating a new system which requires a certain form of denormalized data. It usually involves iterating through the results of … -
Using Travis-CI with Python and Django
I've been using Travis-CI for a while now. Both my personal projects, and even several of the libraries we maintain at DISQUS rely on it for Continuous Integration. I figured it was about time to confess my undenying love for Travis, and throw up some notes about the defaults we use in our projec... -
Using Travis-CI with Python and Django
I’ve been using Travis-CI for a while now. Both my personal projects, and even several of the libraries we maintain at DISQUS rely on it for Continuous Integration. I figured it was about time to confess my undenying love for Travis, and throw up some notes about the defaults we use in our … -
On Fixtures and Factories
We’ve made it a general rule to move away from relying on fixtures in our projects. The main reasons are… -
On Fixtures and Factories
Click here to see this post in it's natural habitat and to watch and leave comments. We’ve made it a general rule to move away from relying on fixtures in our projects. The main reasons are: Fixtures are fragile. They often break when the schema changes or even worse they appear to work but introduce subtle bugs. Extra work is sometimes needed in order to make fixtures portable (for example defining natural keys). Processing large fixtures can be very slow, which slows down installation and testing cycles. Other smart people in the community are recommending the same approach. We look for good tools that are usually classified as either data generation or fixture factory. We’ve had some success with django-whatever and wanted to share a few tips. Some of the benefits of django-whatever: Generating one or many instances of a Model can be done in a line or two of code. Easy to handle things like non-standard primary keys or recursive relationships Using a random generator, you get fuzz testing for free. Like all powerful tools, it is easy to accidentally inflict pain. A few lessons we’ve learned: If you have tests that fail randomly, it may be caused by … -
Python Application Deployment with Native Packages
Speed, reproducibility, easy rollbacks, and predictability is what we strive for when deploying our diverse Python applications. And that’s what we achieved by leveraging virtual environments and Linux system packages. Preamble & Disclaimer To avoid excessive length, I’ll assume you’re somewhat experienced in DevOps/deployment matters and at least loosely familiar with Fabric to follow the examples. I also won’t be explaining configuration management like Ansible, Puppet, Chef or Salt. To reap all of the benefits, you’ll need to run a private debian repository server for your packages. That’s not hard, but it takes some effort. Fortunately, you can avoid running your own debian repository and still gain most of the advantages: a debian package (or a rpm package for that matter) can also be installed by hand using dpkg -i your-package.deb (rpm -Uhv your-package.rpm). If you want to go really light (or don’t have sufficient privileges on the production servers to install packages), you can employ most of the guidelines here except using vanilla tar balls instead of system packages and do the work of the package manager using custom tooling. The key point I’m trying to make is that the best way to have painless and reproducible deployments is … -
Using Travis-CI with Python and Django
I've been using Travis-CI for a while now. Both my personal projects, and even several of the libraries we maintain at DISQUS rely on it for Continuous Integration. I figured it was about time to confess my undenying love for Travis, and throw up some notes about the defaults we use in our projec... -
Working around Django's ORM to do interesting things with GFKs
In this post I want to discuss how to work around some of the shortcomings of djangos ORM when dealing with Generic Foreign Keys (GFKs). At the end of the post I'll show how to work around django's lack of correctly CAST-ing when the generic foreign key is of a different column type than the objects it may point to. A quick primer on content-types and GFKs If the Generic Foreign Key did not exist, it would be necessary to invent it Thanks to the content-types framework, part of django.contrib, we do not have to do any inventing, however. The content-types framework is an app that is responsible for mapping python models to the database layer -- a dirty job, but it makes a number of other things easier to implement. Content-types are used to provide granular permissions via the auth/permissions framework and, notably, they have been used to implement GFKs. A GFK is simply a foreign key to a content-type and an additional column to store a related primary key. It is not really a foreign key at all in the sense of it being an actual database constraint. Nor is it a foreign key in the same sense … -
Working around Django's ORM to do interesting things with GFKs
In this post I want to discuss how to work around some of the shortcomings of djangos ORM when dealing with Generic Foreign Keys (GFKs). At the end of the post I'll show how to work around django's lack of correctly CAST-ing when the generic foreign key is of a different column type than the objects it may point to. -
Working around Django's ORM to do interesting things with GFKs
In this post I want to discuss how to work around some of the shortcomings of djangos ORM when dealing with Generic Foreign Keys (GFKs). At the end of the post I'll show how to work around django's lack of correctly CAST-ing when the generic foreign key is of a different column type than the objects it may point to. A quick primer on content-types and GFKs If the Generic Foreign Key did not exist, it would be necessary to invent it Thanks to the content-types framework, part of django.contrib, we do not have to do any inventing, however. The content-types framework is an app that is responsible for mapping python models to the database layer -- a dirty job, but it makes a number of other things easier to implement. Content-types are used to provide granular permissions via the auth/permissions framework and, notably, they have been used to implement GFKs. A GFK is simply a foreign key to a content-type and an additional column to store a related primary key. It is not really a foreign key at all in the sense of it being an actual database constraint. Nor is it a foreign key in the same sense … -
Working around Django's ORM to do interesting things with GFKs
In this post I want to discuss how to work around some of the shortcomings of djangos ORM when dealing with Generic Foreign Keys (GFKs). At the end of the post I'll show how to work around django's lack of correctly CAST-ing when the generic foreign key is of a different column type than the objects it may point to. A quick primer on content-types and GFKs If the Generic Foreign Key did not exist, it would be necessary to invent it Thanks to the content-types framework, part of django.contrib, we do not have to do any inventing, however. The content-types framework is an app that is responsible for mapping python models to the database layer -- a dirty job, but it makes a number of other things easier to implement. Content-types are used to provide granular permissions via the auth/permissions framework and, notably, they have been used to implement GFKs. A GFK is simply a foreign key to a content-type and an additional column to store a related primary key. It is not really a foreign key at all in the sense of it being an actual database constraint. Nor is it a foreign key in the same sense … -
Working around Django's ORM to do interesting things with GFKs
In this post I want to discuss how to work around some of the shortcomings of djangos ORM when dealing with Generic Foreign Keys (GFKs). At the end of the post I'll show how to work around django's lack of correctly CAST-ing when the generic foreign key is of a different column type than the objects it may point to. A quick primer on content-types and GFKs If the Generic Foreign Key did not exist, it would be necessary to invent it Thanks to the content-types framework, part of django.contrib, we do not have to do any inventing, however. The content-types framework is an app that is responsible for mapping python models to the database layer -- a dirty job, but it makes a number of other things easier to implement. Content-types are used to provide granular permissions via the auth/permissions framework and, notably, they have been used to implement GFKs. A GFK is simply a foreign key to a content-type and an additional column to store a related primary key. It is not really a foreign key at all in the sense of it being an actual database constraint. Nor is it a foreign key in the same sense … -
Three things you should never put in your database
As I've said in a few talks, the best way to improve your systems is by first not doing "dumb things". I don't mean you or your development staff is "dumb", it's easy to overlook the implications of these types of decisions and not realize how bad they are for maintainability let alone scaling. As a consultant I see this stuff all of the time and I have yet to ever see it work out well for anyone. Images, files, and binary data Your database supports BLOBs so it must be a good idea to shove your files in there right? No it isn't! Hell it isn't even very convenient to use with many DB language bindings. There are a few of problems with storing files in your database: read/write to a DB is always slower than a filesystem your DB backups grow to be huge and more time consuming access to the files now requires going through your app and DB layers The last two are the real killers. Storing your thumbnail images in your database? Great now you can't use nginx or another lightweight web server to serve them up. Do yourself a favor and store a simple … -
Los Angeles Open Source Sprint on May 12th!
This is a day long coding event in Los Angeles for Open Source developers of all languages and skill levels to come and code like fiends. They'll be joined by dozens of either really smart coders or nice people like me. Sponsors are providing food, drinks, venue, and more! RSVP at http://www.meetup.com/LA-Hackathons/events/62796642/ before it fills up! It's free. I'll be there to: Organize the event with the assistance of the awesome Los Angeles technical community! Code like a fiend. I want to work on django-mongonaut and could use some GraphViz and JavaScript help. And now to open the floor to questions... Where and when? Where: Spire.io 7257 Beverly Blvd #210 Los Angeles, CA 90036 When: May 12, 2012 10 AM to 10 PM Is this like a Hackathon? Yup. See http://en.wikipedia.org/wiki/Hackathon#Sprints Will there be Wifi? Yes! I'm just starting as a developer, should I come? It depends. If you've never coded before, this isn't the right place. Instead, you might consider one of the local coding workshops or classes. In fact, here's a good bi-weekly hack night / study group for you. If you've done a tutorial or two, sprints can be a great way to learn new skills or … -
Los Angeles Open Source Sprint on May 12th!
This is a day long coding event in Los Angeles for Open Source developers of all languages and skill levels to come and code like fiends. They'll be joined by dozens of either really smart coders or nice people like me. Sponsors are providing food, drinks, venue, and more! RSVP at http://www.meetup.com/LA-Hackathons/events/62796642/ before it fills up! It's free. I'll be there to: Organize the event with the assistance of the awesome Los Angeles technical community! Code like a fiend. I want to work on django-mongonaut and could use some GraphViz and JavaScript help. And now to open the floor to questions... Where and when? Where: Spire.io 7257 Beverly Blvd #210 Los Angeles, CA 90036 When: May 12, 2012 10 AM to 10 PM Is this like a Hackathon? Yup. See http://en.wikipedia.org/wiki/Hackathon#Sprints Will there be Wifi? Yes! I'm just starting as a developer, should I come? It depends. If you've never coded before, this isn't the right place. Instead, you might consider one of the local coding workshops or classes. In fact, here's a good bi-weekly hack night / study group for you. If you've done a tutorial or two, sprints can be a great way to learn new skills or … -
Managing multiple SSH identities
Here at Imaginary we maintain our own git repositories internally with the help of the invaluable utility, Gitolite. This works well for us. However, in some cases, our clients have their own repositories that we must interact with. The problem arises when the client repositories reside on a third-party service ...
