09 Oct 2015 code

Recently I started a new Django project, and this time I decided to go all in on Docker. No virtualenvs, no local databases - containers all the way.

There are about a million and 10 articles about how to dockerize webapps by now. However, none of them seem to address one simple fact: we don't simply want to dockerize our applications, we want to develop them too!

sane-django-docker is cotains a sample django project webapp as well as the necessary config files to run both a development and production server.

Checkout and Go®

One of my goals was to make the codebase development first. One should be able to checkout the the codebase and run at most two or three commands to have a real development environment set up. This means we should have a live-reloading django development server, debug mode on, and a postgresql database. I also can't stand logic in my settings.py files, so it is left as vanilla as possible. It will import a local_settings.py file at the end, but besides that it is 100% constants. No os.getenv() to be found.

To start the development server simple run:


Django will complain about the postgres database not existing so we'll create one:

docker exec sanedjangodocker_db_1 createdb -Upostgres webapp

Sweet Jane! We now have a django development server running at http://localhost:8000 along with a postgresql database! Make a code change and watch it reload. This is how code was meant to be written.

So what's the secret sauce? A super simple Dockerfile and an equally simple docker-compose-dev.yml file.

Keen observers will notice that docker-compose won't actually run with a file called docker-compose-dev.yml. This is very true, and it only works because docker-compose.yml is actually a symlink:

├── docker-compose-dev.yml
├── docker-compose-prod.yml
├── docker-compose.yml -> docker-compose-dev.yml

Notice we also have a docker-compose-prod.yml file. Now that we are ready to push to production, let's see what that other file is all about:

Deployment ain't that much harder

So getitng a dev environment up and running is all well and good, but we are going to have to deploy our code at some point. Deployment takes a few additional steps, but then again deployment probably should.

Let's take a look at what we have:

├── deploy
│   ├── local_settings.py
│   ├── nginx-app.conf
│   ├── supervisor-app.conf
│   ├── uwsgi.ini
│   └── uwsgi_params
├── docker-compose-dev.yml
├── docker-compose-prod.yml
├── docker-compose.yml -> docker-compose-dev.yml
├── Dockerfile
├── Dockerfile.prod
├── .gitignore
├── manage.py
├── README.md
├── requirements.txt
└── webapp
    ├── __init__.py
    ├── settings.py
    ├── urls.py
    └── wsgi.py

The deploy/ directory contains all our server configuration files. The directory also includes our local_settings.py which contains our production config. It is included in .gitignore and should not be included in source control!

Dockerfile.prod is our production dockerfile. It is based on python:3.5, installs nginx, uwsgi and supervisord, copies our config files and finally runs manage.py collectstatic.

Let's build an image from it:

docker build -f Dockerfile.prod -t webapp:latest .

That's it! our production image is ready to go. To test it out locally first, we can run it:

rm docker-compose.yml
ln -s docker-compose.prod.yml docker-compose.yml
docker-compose up

This should start our project in production mode, using the image we just built. Again, we need to initially create the database, and we should probably run migrations too:

docker exec sanedjangodocker_db_1 createdb -Upostgres webapp
docker exec sanedjangodocker_web_1 python3 manage.py migrate

Navigate to localhost:8700 and see your production ready application being served!

Where to go from here

There are probably a few things you want to tweak for a real project such as the postgresql data volume in docker-compose-prod.yml, and your ALLOWED_HOSTS setting in local_settings.py.

Of course, the nginx, uwsgi and supervisord config files are pretty basic, and probably should be scrutinized before a real life deploy.


All in all, I've found this to be a pretty frinctionless workflow. The one annoyance I have is that both dockerfiles have to be in the top level directory, that's due to how docker sends the build context to the server. Besides that there isn't much to complain about - I'll probably use this as a base for my future projects.

10 Aug 2015 linux

I've been pretty good about not becoming a open source pundit. But today I feel like writing something useless.

My laptop's ssd crapped out yesterday so I spent the day restoring backups and installing operating systems. I've been using Ubuntu for a few years now, so I thought it would be great to revisit Gnome and see how the 3.x development is coming along, maybe even switch back.


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22 May 2015 other

I was waiting in line at the supermarket this morning when I came across this cover of the June 2015 Vanity Fair:

Vanity Fair

Immediately something struck me as very, very wrong.

I know we all hope the new Star Wars will be good and make up for the complete travesty of episodes I, II and III. But I'm going to make a quick and uninformed judgment based solely on this magazine cover and say: no, no it won't.

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29 Apr 2015 code

I just upgraded this VPS from Debian Wheezy to Jessie. The upgrade went pretty flawless, excpet some minor issues with postgres and the new bad systemd smell.

However, if you are running NGINX + PHP5-fpm, you may want to read the news that gets displayed during the upgrade:

nginx shipped a modified `fastcgi_params`, which declared `SCRIPT_FILENAME`
fastcgi_param. This line has now been removed. From now on we are also
shipping fastcgi.conf from the upstream repository, which includes a sane
`SCRIPT_FILENAME` parameter value.

So, if you are using fastcgi_params, you can try switching to fastcgi.conf
or manually set the relevant params.

After the upgrade, I was getting blank responses from nginx for all php scripts. No errors in nginx or fpm logs. After re-reading the news above, the following fix worked for me:

In /etc/nginx/sites-available/* change

include fastcgi_params


include fastcgi.conf

Hope this helps anyone in need.

Flammarion Engraving

I created AstroChallenge to scratch my own itch: to have a place to keep an observation journal for astronomy and to share it with the rest of the community. In that I believe I've succeeded, check out my profile and journal.

Since then the word has gotten out and other astronomers have been logging their own observations. Now, only 2 weeks after making AstroChallenge public, over 100 observations have been logged! I want to thank everyone who has helped me make AstroChallenge awesome by providing great feedback and ideas.

It's been a fun project so far and I look forward to seeing where it goes from here. Most of all, I wish everyone clear skies! Keep looking up.

26 Mar 2015 other

The following is a excerpt from the book I am currently reading by Richard Feynman, Surely You Must be Joking, Mr. Feynman! that I found amusing.

Well, Mr. Frankel, who started this program, began to suffer from the computer disease that anybody who works with computers now knows about. It's a very serious disease and it interferes completely with the work. The trouble with computers is you play with them. They are so wonderful. You have these switches--if it's an even number you do this, if it's an odd number you do that--and pretty soon you can do more and more elaborate things if you are clever enough, on one machine.

After a while the whole system broke down. Frankel wasn't paying any attention; he wasn't supervising anybody. The system was going very, very slowly--while he was sitting in a room figuring out how to make one tabulator automatically print arc-tangent X, and then it would start and it would print columns and then bitsi, bitsi, bitsi and calculate the arc-tangent automatically by integrating as it went along and make a whole table in one operation.

Absolutely useless. We had tables of arc-tangents. But if you've ever worked with computers, you understand the disease--the delight in being able to see how much you can do. But he got the disease for the first time, the poor fellow who invented the thing.

Still suffering to this day!

25 Feb 2015 astrochallenge, astronomy, code

I've spent a good deal of time in the last few days searching for a good library to draw star charts (finder charts) that I could use to integrate with AstroChallenge. While there are plenty of utilities to create star maps, they mostly consist of desktop software or websites that are not open source.


Eventually I found fchart which resembled was I was looking for. A set of python scripts with minimal dependencies that would output star maps! This I could use.

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23 Feb 2015 cartography, code, granitemaps

After much ado, the latest map from GraniteMaps is now available. This map covers 2 distinct areas; The first is Soquel Demonstration Forest, well known in the mountain biking community as having miles of challenging, technical singletrack. The other is the Forest of Nisene Marks which shares a ridge with Demo and provides trail users of all types some of the most pristine redwood forest trails available in California.

This new map is much improved over the last version for Santa Cruz by having a brand new base layer. This is a custom topographic map I designed myself (detailed in this post) which combines OpenStreetMap and SRTM data to create a concise, easy to read map. I hope you enjoy it.

Thanks everyone for your kind words and support! The reception I received for the Santa Cruz map was fantastic, far exceeding anything I could have imagined while creating it!


20 Feb 2015 astrochallenge, astronomy, code

I've been working on new project recently called AstroChallenge. While the details of what exactly AstroChallenge is will have to come later, rest assured, it has to do with Astronomy.

right ascension

One of the bits of information I'm interested in is whether a particular celestial object is visible in the sky or not. Given an observer's latitude, longitude and elevation and an object's right ascension and declination it becomes a straightforward calculation.

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23 Jan 2015 greece

I met Amalia at the Thessaloniki Pythess (Python) meetup (at which I gave one awkward english presentation) which had migrated to a lounge under the Archaeological Museum of Thessaloniki. I thought the museum looked pretty cool, so I decided I would go the next day. I propositioned the group to see if anyone else was interested in joining me, Amalia was the only one brave enough to to say so.


We spent a few good hours at the museum and various other historical points of interest around the city. While walking down some buzzing, narrow street Amalia told me a great story about how it is that Greeks came to find themselves in Greece:

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