OS X Django dev environment: linking to virtualenv django and apps media - django

I am developing a Django app on Mac OS 10.8. The production server is an Ubuntu server. On the production server, I created symlinks to the directory below:
(On Ubuntu)
/var/virtualenvs/some_virtualenv/lib/python2.6/site-packages/django/contrib/admin/media
But those symlinks obviously don't work in my local OS X dev environment:
(On OS X)
/Users/username/Webdev/.virtualenvs/some_virtualenv/lib/python2.7/site-packages/django/contrib/admin/media
The symlink apparently made it into the git repo. Django deployment really is a bit of a pain! Can someone tell me how to deal with deployment in two different environments?
UPDATE: Is it simply a matter of making sure the symlinks are excluded from the git?

Django deployment really isn't too hard, but there are a couple of patterns that are useful. The first, is to split out your production and development settings. There are a number of different ways to do this, most of which are described in the django documentation.
Also, if you're using Django >= 1.4, you don't need to symlink to admin media anymore since it has been converted to using staticfiles.
I use this template when creating any new django 1.4 projects, which includes generating your production and local settings.
Symlinks shouldn't be included in your git repo IMO. There are better ways of managing how to access your media.

Related

Deployment of Django in local network while continuing development

The question is in the title.
I need to deploy a Django application in a local network (i still don't know how to do but i suppose it's quite easy) but i still need to develop it. My question is how to do to allow users to use the application while i'm still developing it ?
Is it a solution to keep to versions of the application, one deployed and one in development ? In this way, I can replace the application deployed by the newly developed one when I finish coding it.
Another question concerns the database, can I still modify the database if I just add new models without touching existing ones ?
Thank you in advance,
This is a good blog entry that covers deploying Django using Heroku. I'll give you a quick rundown of what makes all the different technologies important:
Git
Git, or any other version control system, is certainly not required. Why it lends itself to deploying Django projects is that your usually distributing your application by source, i.e. your not compiling it or packaging it as an egg. Usually you'll organize your Git repository as such that updating your application on the server only requires you to do a checkout of the latest sources--nothing else.
virtualenv and pip
This, again, is not a strict requirement, but I'd strongly suggest you take the time to familiarize yourself with virtualenv and pip if you already haven't done so, since it's going to make deploying your Python applications across different runtime environments, local or remote, a breeze.
Basically, your project will need to have at least Django and Gunicorn available on the Python path, possibly even a database driver. What that means is that every time you try to deploy your application somewhere you'll have to install Python and do the easy_install dance all over.
virtualenv will redistribute a Python installation, which in turn means that the new Python instance will, by default, have it's very own Python path configuration relative to the installation. pip is like easy_install on steroids, since it supports checking out Python dependencies directly from code repositories and supports a requirements file format with which you can install and configure all of your dependencies in one fell swoop.
With virtualenv and pip, all you'd need to do is have a simple text file with all your dependencies that can be parsed with pip and an installed Python distribution on the machine. From there you just do git checkout repo /app/path; easy_install virtualenv; virtualenv /app/path; ./app/path/scripts/activate; pip install -r /app/path/requirements.txt. Voila, Gunicorn, Django and all other dependencies are then installed and available immediately. When you run the Gunicorn Django script with the Python instance in /app/path/scripts, then the script will immediately have access to the Gunicorn sources and it will be able to locate your Django project which will have access to Django and other dependencies as well.
Gunicorn
This is the actual Python application that will manage your Django instance and provide an HTTP interface that exposes it to HTTP clients. It'll start several worker processes which will all be distinct Python virtual machines loaded with the sources of your application and it's dependencies. The main Gunicorn process will in turn take charge of managing which worker processes manage which requests for maximum throughput.
The basic principle of wiring Nginx and Gunicorn
The most important thing to observe is that Nginx and Gunicorn are separate processes that you manage independently.
The Nginx Web server will be publicly exposed, i.e. it will be directly accessible over the internet. For requests to static media, such as actual images, CSS stylesheets, JavaScript sources and PDF files accessible via the filesystem, Nginx will take charge of returning them in the response body to HTTP clients if you configure it to look for files on the path where you configured your project to collect static media.
Any other request should be proxied to your Gunicorn instance. It will be configured to listen to HTTP requests on a certain port on the loopback interface, so you'll using Nginx as a revers proxy to http://127.0.0.1:8080 for requests to your Django instance.
This is the basic rundown for deploying your Django projects into production that should satisfy the needs of 95% Django projects running out there. While I did reference Nginx and Gunicorn, it's the usual approach when it comes to setting up any Web server to act as a reverse-proxy to a Python WSGI server.

Deploying Django App on Heroku using Windows

I want to deploy my django app on heroku , which I have built on Windows machine.
Can I deploy the same application using heroku toolbelt for windows.
Or I have to setup all the things on a unix machine.
And one more thing the application uses Python 3 and Django 1.8
Will that be any problem.
There aren't any special process listed in the docs for windows usersYou should actually deploy from a unix environment, you have to create your Procfile, requirements.txt and make some changes to your settings.py file, it's easy and straight forward.
A step by step guide can be found here https://devcenter.heroku.com/articles/getting-started-with-django
Some problems you may encouter:
Internal Server Error heroku/django
Django migrations fail in heroku
Also make sure you add your migrations and cache folders to your .gitignore file.

Django site on Webfaction - how the flow of information works, and integrating with Pycharm remote dev

I have been learning Django in the development mode for a two months and I am up to speed with most basic aspects of python + django now. However, I was using the built-in runserver till this time
Now, I have got a Webfaction hosting account and wanted to know the following
1) Webfaction sets up the project with a certain Django version (say 1.6.4) and Python version (say 2.7) initially
The project directory (for say project MYAPP) is /<>/webapps/MYAPP
When the site is running in production mode, how does the apache server know which Python version, and which site-packages versions to use with the MYAPP source code to render the site?
I can see that the MYAPP folder has a lib/python2.7 folder, however when I am connected to SSH terminal, and do a "which python", i see :
which python
/usr/local/bin/python
so, do I take that this is the Python executable that is being used for rendering the website instead of the one in webapps/MYSITE/lib/python2.7 folder? How does the information/data flow about which programs to use during rendering the site with apache mod_wsgi work?
2) I was using a virtualenv in the development mode during testing. How do I use this on webfaction in production mode?
3) I am using Pycharm IDE. It worked well for the development mode. I can see that it has a remote interpreter configuration and a Deployment setting/option.
The python path that the remote interpreter settings tool detects automatically is the python executable at /usr/local/bin/python
Is this fine, or should I be pointing it to the more local python2.7 in the webapps/lib folder?
Thanks a lot of the answers and pls let me know if you need any supplemental info
Note to the OP: This should really be three separate questions.
1) For WebFaction, your Django app will use the Python version (and libraries, etc.) defined in:
~/webapps/<appname>/apache2/conf/httpd.conf
Specifically, you'll want to look at what is defined for WSGIPythonPath (which should mostly match up with WSGIDaemonProcess unless you modify the config and are doing something strange).
Note that which python just tells you what the default python is in your shell. This has nothing to do with the config file for the webapp.
2) You may want to expand on this as to exactly what your use case is and why the default Django webapp created by WebFaction doesn't fit your needs. But the short answer is:
Create a virtualenv on your WebFaction account.
Install Django, etc. into the virtualenv.
Edit the httpd.conf file I mentioned above to use your virtualenv instead.
I've done this with both a Django webapp made via the WebFaction control panel and via a custom mod_wsgi webapp. So it does work. Just make sure to use the right Python version when making your virtualenv.
3) I don't use PyCharm so I can't answer this (one reason why this question should be split up).

django virtualenv vs repository packages

I'm new to django and I'm trying to find out which way to build project is better:
Build own virtualenv for each (including core django packages, which available via systemm repository) project
or
use packages from debian repository (if available, otherwise put it in virtualenv).
As I understand, in case any security update the repository version will receive patch asap, however virtualenv version I'll need patch myself.
However in case of movement to another server virtual will cause less issues, then repository version.
What is the best practices?
As far as I know virtualenv is used by almost every django developer.
It is also good practice to have versions in your requirements.txt so that if some of the packages change you'll have your project working in production.
I think virtualenv is de facto the best practice for development with Python (not just with Django)

Producing a WAR file from a django project with SQLite

I have a django project (a django module/app some other modules that are used from the django one) that uses SQLite. This project is for a University course and now I am asked to supply it in such a way so that it may be installed on some server in our faculty. I'm not the one who's going to install it, and I will not be contacted in case of failure, so I am looking for the easiest, simplest way to supply the project for installation.
I have come across django-jython which supposedly allows one to create WAR files from django projects. However, in the Database Backends section, it says:
SQLite3
Experimental. By now, use it only if you are working on improving it. Or if you are really adventurous.
My overall goal is to deliver this project and I would appreciate any helpful advice. In particular:
Is there another way to pack a django project into a WAR file that supports SQLite?
Is it safe to use SQLite with django-jython in spite of this warning? If so, then how?
Is there any other simple way to pack a django project so that it'll be a piece of cake to install?
If the above answers are "no", then what does it take to change the configuration of the project to use MySQL instead?
You should look into Fabric for easy deployment. I haven't used it myself, but I've heard good things.
I've also had good success quickly and easily setting up servers using Gunicorn with Nginx as a reverse-proxy.
As others have said, using virtualenv, with pip, can quickly
get all your dependencies installed via requirements.txt (from virtualenv).
Some of these blog posts may help:
Tools of the modern Python hacker - virtualenv, pip, fabric
Basic Django Deployment - virtualenv, pip, fabric, rsync
Easy Django Deployment - very quick nginx and gunicorn setup
Edit:
As I reread your post I saw your last bullet point/question. Django is designed to be loosely coupled, meaning that there shouldn't (in most cases) be reasons that one app is dependant on sqlite vs mysql. If you don't need to save the data in the db, changing to MySQL is as easy as starting a mysql server on your machine, and changing the settings.py of your django project. This SO question may help