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<!DOCTYPE html>
<html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta charset="utf-8">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="author" content="Matt Makai">
<meta name="description" content="Full Stack Python explains each layer of the web application stack, from the server up through the rendering in a user's browser.">
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<title>Full Stack Python</title>
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<h1>Introduction</h1>
<p>You're knee deep in learning the <a href="http://www.python.org/">Python</a>
programming language. The syntax is starting to make sense. The first
few "<em>ahh-ha</em>!" moments are hitting you as you're learning conditional
statements, for loops and classes while playing around with the open source
libraries that make Python such an amazing language.</p>
<p>Now you want to take your initial Python knowledge and make something real.
A real web application that's available on the web which you can show off or
sell as a service to other people. That's where Full Stack Python comes in.
You've come to the right place to learn everything you need to deploy and
run a production Python web application.</p>
<p>This guide branches out on topic because your learning needs depend on what
you're currently trying to do. </p>
<h3>Let's get started. What do you need to do right now?</h3>
<h1>Web frameworks</h1>
<p>A web application framework is a code library that makes a developer's life
easier when building reliable, scalable and maintainable web applications.</p>
<h2>Why are web frameworks necessary?</h2>
<p>Web frameworks encapsulate what developers have learned over the past twenty
years while building dynamic web applications. Frameworks make it easier
to reuse code for common HTTP operations and to structure your code so that
it is maintainable.</p>
<h2>Common web framework functionality</h2>
<p>Frameworks provide functionality in their code or through extensions to
perform common operations required to run web applications. These common
operations include:</p>
<ol>
<li>URL routing</li>
<li>HTML, XML, JSON, and other output format templating</li>
<li>Database manipulation</li>
<li>Security against Cross-site request forgery (CSRF) and other attacks</li>
</ol>
<p>Not all web frameworks include code for all of the above
functionality. Frameworks fall somewhere between simply executing a
single use case and attempting to be everything to every developer with
increased complexity. Some frameworks take the "batteries-included" approach
where everything possible comes bundled with the framework while others
have a minimal code library that plays well with extensions.</p>
<p>For example, the Django web application framework includes an
Object-Relational Mapping (ORM) layer that abstracts relational database
read, write, query, and delete operations. However, Django's ORM
cannot work without significant modification on non-relational databases such as
<a href="http://www.mongodb.org/">MongoDB</a>.
Some other web frameworks such as Flask and Pyramid are easier to
use with non-relational databases by incorporating external Python libraries.
There is a spectrum between minimal functionality with easy extensibility and
including everything in the framework with tight integration.</p>
<h2>General web framework resources</h2>
<ul>
<li>
<p>"<a href="http://www.jeffknupp.com/blog/2014/03/03/what-is-a-web-framework/">What is a web framework?</a>"
by <a href="https://twitter.com/jeffknupp">Jeff Knupp</a>
is an in-depth explanation of what a web framework is and their relation
to web servers.</p>
</li>
<li>
<p>Check out the answer to the
"<a href="http://stackoverflow.com/questions/4507506/what-is-a-web-framework-how-does-it-compare-with-lamp">What is a web framework and how does it compare to LAMP?</a>"
question on Stack Overflow.</p>
</li>
<li>
<p>This <a href="http://www.konstruktor.ee/blog/python-web-framework-roundup/">Python web framework roundup</a>
covers Django, Flask and Bottle as well as several other lesser known Python
frameworks.</p>
</li>
<li>
<p>This fascinating blog post takes a look at the
<a href="http://grokcode.com/864/snakefooding-python-code-for-complexity-visualization/">code complexity of several Python web frameworks</a>
by providing visualizations based on their code bases.</p>
</li>
</ul>
<h2>Web frameworks learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
Choose a major Python web framework (<a href="/django.html">Django</a> or
<a href="/flask.html">Flask</a> are recommended) and stick with it. When you're just
starting it's best to learn one framework first instead of bouncing around
trying to understand every framework. </p>
<p><i class="fa fa-check-square-o"></i>
Work through a detailed tutorial found within the resources links on the
framework's page.</p>
<p><i class="fa fa-check-square-o"></i>
Study open source examples built with your framework of choice so you can
take parts of those projects and reuse the code in your application.</p>
<p><i class="fa fa-check-square-o"></i>
Build the first simple iteration of your web application then go to
the <a href="/deployment.html">deployment</a> section to make it accessible on the
web.</p>
<h3>Which web framework do you want to learn about?</h3>
<h1>Django</h1>
<p><a href="http://www.djangoproject.com/">Django</a> is a widely used Python web
application framework with a "batteries-included" philosophy. The principle
behind batteries-included is that the common functionality for building
web applications should come with the framework instead of as separate
libraries. </p>
<p><a href="http://www.djangoproject.com/" style="border: none;"><img src="theme/img/django-logo-positive.png" width="100%" alt="Official Django logo. Trademark Django Software Foundation." class="technical-diagram" /></a></p>
<p>For example,
<a href="https://docs.djangoproject.com/en/dev/topics/auth/">authentication</a>,
<a href="https://docs.djangoproject.com/en/dev/topics/http/urls/">URL routing</a>, a
<a href="https://docs.djangoproject.com/en/dev/topics/templates/">templating system</a>,
an <a href="https://docs.djangoproject.com/en/dev/topics/db/">object-relational mapper</a>,
and <a href="https://docs.djangoproject.com/en/dev/topics/migrations/">database schema migrations</a>
(as of version 1.7) are all included with the <a href="https://pypi.python.org/pypi/Django/1.6.2">Django framework</a>.
Compare that included functionality to the Flask framework which requires a
separate library such as
<a href="https://flask-login.readthedocs.org/en/latest/">Flask-Login</a>
to perform user authentication. </p>
<p>The batteries-included and extensibility philosophies are simply two different
ways to tackle framework building. Neither philosophy is inherently better
than the other.</p>
<h2>Why is Django a good web framework choice?</h2>
<p>The Django project's stability, performance and community have grown
tremendously over the past decade since the framework's creation. Detailed
tutorials and best practices are readily available on the web and in books.
The framework continues to add significant new functionality such as
<a href="https://docs.djangoproject.com/en/dev/topics/migrations/">database migrations</a>
with each release. </p>
<p>I highly recommend the Django framework as a starting place for new Python web
developers because the official documentation and tutorials are some of the
best anywhere in software development. Many cities also have Django-specific
groups such as <a href="http://www.meetup.com/django-district/">Django District</a>,
<a href="http://www.meetup.com/djangoboston/">Django Boston</a> and
<a href="http://www.meetup.com/The-San-Francisco-Django-Meetup-Group/">San Francisco Django</a>
so new developers can get help when they are stuck.</p>
<p>There's some debate on whether
<a href="http://www.jeffknupp.com/blog/2012/12/11/learning-python-via-django-considered-harmful/">learning Python by using Django is a bad idea</a>.
However, that criticism is invalid if you take the time to learn the Python
syntax and language semantics first before diving into web development.</p>
<h2>Django tutorials</h2>
<ul>
<li>
<p><a href="http://www.tangowithdjango.com/book/">Tango with Django</a> are a extensive
free introductions to using the most popular Python web framework. Several
current developers said this book really helped them get over the initial
framework learning curve.</p>
</li>
<li>
<p><a href="http://twoscoopspress.com/products/two-scoops-of-django-1-6">2 Scoops of Django</a>
by Daniel Greenfeld and Audrey Roy is well worth the price of admission if
you're serious about learning how to correctly develop Django websites.</p>
</li>
<li>
<p><a href="http://effectivedjango.com/">Effective Django</a> is another free introduction
to the web framework.</p>
</li>
<li>
<p>The <a href="http://www.reddit.com/r/django">Django subreddit</a> often has links to
the latest resources for learning Django and is also a good spot to ask
questions about it.</p>
</li>
<li>
<p>Lincoln Loop wrote a
<a href="http://lincolnloop.com/django-best-practices/">Django Best Practices guide</a>
for the community.</p>
</li>
<li>
<p>Steve Losh wrote an incredibly detailed <a href="http://stevelosh.com/blog/2011/06/django-advice/">Django Advice guide</a>.</p>
</li>
<li>
<p><a href="http://programming.oreilly.com/2014/04/simplifying-django.html">Lightweight Django</a>
has several nice examples for breaking Django into smaller simplier
components.</p>
</li>
<li>
<p>The <a href="https://github.com/rogueleaderr/definitive_guide_to_django_deployment">Definitive Guide to Django Deployment</a>
explains the architecture of the resulting set up and includes Chef scripts
to automate the deployment.</p>
</li>
<li>
<p><a href="http://agiliq.com/blog/2014/08/deploying-a-django-app-on-amazon-ec2-instance/">Deploying a Django app on Amazon EC2 instance</a>
is a detailed walkthrough for deploying an example Django app to Amazon
Web Services.</p>
</li>
<li>
<p><a href="http://www.nickpolet.com/blog/deploying-django-on-aws/1/">Deploying Django on AWS</a>
is another walkthrough for deploying Django to AWS.</p>
</li>
<li>
<p><a href="https://github.com/rosarior/awesome-django">django-awesome</a> is a curated
list of Django libraries and resources.</p>
</li>
<li>
<p><a href="https://realpython.com/learn/start-django/">Starting a Django Project</a> answers the question, “How do I setup a Django (1.5, 1.6, or 1.7) Project from scratch?”</p>
</li>
</ul>
<h2>Django videos</h2>
<ul>
<li>
<p><a href="https://godjango.com/">GoDjango</a> screencasts and tutorials are free short
videos for learning how to build Django applications.</p>
</li>
<li>
<p>Ontwik has learning videos in its
<a href="http://ontwik.com/category/django/">Django category</a>.</p>
</li>
<li>
<p><a href="http://pyvideo.org/video/2630/designing-djangos-migrations">Designing Django's Migrations</a>
covers Django 1.7's new migrations from the main programmer Andrew Godwin.</p>
</li>
<li>
<p><a href="http://gettingstartedwithdjango.com/">Getting Started with Django</a> is a
series of video tutorials for the framework.</p>
</li>
<li>
<p>DjangoCon US videos from
<a href="http://www.youtube.com/user/TheOpenBastion/videos">2013</a>,
<a href="http://pyvideo.org/category/23/djangocon-2012">2012</a>,
<a href="http://pyvideo.org/category/3/djangocon-2011">2011</a>, as well as<br />
<a href="http://pyvideo.org/category">earlier US and DjangoCon EU conferences</a> are
all available free of charge.</p>
</li>
</ul>
<h2>Django ORM resources</h2>
<p>The <a href="https://docs.djangoproject.com/en/dev/topics/db/">Django ORM</a> works well
for simple and medium-complexity database operations. However, there are often
complaints that the ORM makes complex queries much more complicated than
writing straight SQL or using <a href="http://www.sqlalchemy.org/">SQLAlchemy</a>. </p>
<p>It's technically possible to drop down to SQL but it ties the queries to a
specific database implementation. The ORM is coupled closely with Django so
replacing the default ORM with SQLAlchemy is currently a hack workaround. Note
though that some of the Django core committers believe it is only a matter of
time before the default ORM is replaced with SQLAlchemy. It will be a large
effort to get that working though so it's likely to come in Django 1.9 or
later.</p>
<p>Since the majority of Django projects are tied to the default ORM, it's best to
read up on advanced use cases and tools for doing your best work within the
existing framework.</p>
<ul>
<li>
<p><a href="http://django-debug-toolbar.readthedocs.org/en/1.2/">Django Debug Toolbar</a>
is a powerful Django ORM database query inspection tool. Highly recommended
during development to ensure you're writing reasonable query code.
<a href="http://mtford.co.uk/blog/2/">Django Silk</a> is another inspection tool and
has capabilities to do more than just SQL inspection.</p>
</li>
<li>
<p><a href="http://reinout.vanrees.org/weblog/2014/05/06/making-faster.html">Making a specific Django app faster</a>
is a Django performance blog post with some tips on measuring performance
and optimizing based on the measured results.</p>
</li>
<li>
<p><a href="https://speakerdeck.com/alex/why-i-hate-the-django-orm">Why I Hate the Django ORM</a>
is Alex Gaynor's overview of the bad designs decisions, some of which he
made, while building the Django ORM.</p>
</li>
<li>
<p><a href="https://speakerdeck.com/craigkerstiens/going-beyond-django-orm-with-postgres">Going Beyond Django ORM with Postgres</a>
is specific to using PostgreSQL with Django.</p>
</li>
</ul>
<h2>Open source Django example projects</h2>
<ul>
<li>
<p><a href="https://github.com/makaimc/txt2react">Txt 2 React</a> is a full Django web
app that allows audiences to text in during a presentation with feedback
or questions.</p>
</li>
<li>
<p><a href="https://github.com/ustream/openduty">Openduty</a> is a website status checking
and alert system similar to PagerDuty.</p>
</li>
<li>
<p><a href="https://github.com/myusuf3/courtside">Courtside</a> is a pick up sports web
application written and maintained by the author of PyCoder's Weekly.</p>
</li>
<li>
<p>These two Django Interactive Voice Response (IVR) system web application
repositorities <a href="https://github.com/phalt/twilio-django-part-1">part 1</a> and
<a href="https://github.com/phalt/twilio-django-part-2">part 2</a> show you how to
build a really cool Django application. There's also an accompanying
<a href="https://www.twilio.com/blog/2014/07/build-an-ivr-system-with-twilio-and-django.html">blog post</a>
with detailed explanations of each step.</p>
</li>
</ul>
<h2>Django project templates</h2>
<ul>
<li>
<p><a href="https://github.com/caktus/django-project-template">Caktus Group's Django project template</a>
is Django 1.6+ ready.</p>
</li>
<li>
<p><a href="https://github.com/pydanny/cookiecutter-django">Cookiecutter Django</a> is a
project template from Daniel Greenfeld, for use with Audrey Roy's
<a href="https://github.com/audreyr/cookiecutter">Cookiecutter</a>. Heroku
deployment-ready.</p>
</li>
<li>
<p><a href="https://github.com/twoscoops/django-twoscoops-project">Two Scoops Django project template</a>
is also from the PyDanny and Audrey Roy. This one provides a quick scaffold
described in the Two Scoops of Django book.</p>
</li>
</ul>
<h2>Django learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
<a href="https://docs.djangoproject.com/en/dev/topics/install/">Install Django</a> on
your local development machine.</p>
<p><i class="fa fa-check-square-o"></i>
Work through the initial
<a href="https://docs.djangoproject.com/en/dev/intro/tutorial01/">"polls" tutorial</a>.</p>
<p><i class="fa fa-check-square-o"></i>
Build a few more simple applications using the tutorial resources found
in the "Django resources" section.</p>
<p><i class="fa fa-check-square-o"></i>
Start coding your own Django project with help from the
<a href="https://docs.djangoproject.com/en/dev/">official documentation</a> and
resource links below. You'll make plenty of mistakes which is critical
on your path to learning the right way to build applications.</p>
<p><i class="fa fa-check-square-o"></i>
Read <a href="http://www.amazon.com/Two-Scoops-Django-Best-Practices/dp/098146730X/ref=sr_1_2?ie=UTF8&qid=1391562062&sr=8-2&tag=mlinar-20">2 Scoops of Django</a>
to understand Django best practices and learn better ways of building
Django web applications.</p>
<p><i class="fa fa-check-square-o"></i>
Move on to the <a href="/deployment.html">deployment section</a> to get your Django
project on the web.</p>
<h3>What do you need to learn next for your Django app?</h3>
<h1>Flask</h1>
<p><a href="http://flask.pocoo.org/">Flask</a> is a Python web framework built with a
<a href="http://flask.pocoo.org/docs/design/">small core and easy-to-extend philosophy</a>.
<a href="http://flask.pocoo.org/" style="border: none;"><img src="theme/img/flask.png" width="100%" alt="Official Flask logo. Flask Artwork License." class="technical-diagram" /></a></p>
<h2>Why is Flask a good web framework choice?</h2>
<p>Flask is considered more
<a href="http://stackoverflow.com/questions/58968/what-defines-pythonian-or-pythonic">Pythonic</a>
than Django because Flask web application code is in most cases more explicit.
Flask is easy to get started with as a beginner because there is little
boilerplate code for getting a simple app up and running. </p>
<p>For example, here's a valid "hello world" web application with Flask (the
equivalent in Django would be significantly more code):</p>
<div class="codehilite"><pre><span class="n">from</span> <span class="n">flask</span> <span class="n">import</span> <span class="n">Flask</span>
<span class="n">app</span> <span class="o">=</span> <span class="n">Flask</span><span class="p">(</span><span class="n">__name__</span><span class="p">)</span>
<span class="err">@</span><span class="n">app</span><span class="p">.</span><span class="n">route</span><span class="p">(</span><span class="sc">'/'</span><span class="p">)</span>
<span class="n">def</span> <span class="n">hello_world</span><span class="p">()</span><span class="o">:</span>
<span class="k">return</span> <span class="err">'</span><span class="n">Hello</span> <span class="n">World</span><span class="o">!</span><span class="err">'</span>
<span class="k">if</span> <span class="n">__name__</span> <span class="o">==</span> <span class="err">'</span><span class="n">__main__</span><span class="err">'</span><span class="o">:</span>
<span class="n">app</span><span class="p">.</span><span class="n">run</span><span class="p">()</span>
</pre></div>
<p>Flask was also written several years after Django and therefore
learned from the Python community's reactions as the framework evolved.
Jökull Sólberg wrote a great piece articulating to this effect in his
<a href="http://jokull.calepin.co/my-flask-to-django-experience.html">experience switching between Flask and Django</a>.</p>
<h2>Flask resources</h2>
<p>The 18-part Flask mega tutorial is an absolutely amazing starting
resource for using the Flask framework. Yes, there are a lot of posts in
the series. However, each post is focused on a single topic to contain
the complexity while the reader is learning the framework. The whole
series is well worth an in-depth read-through. The
<a href="https://twitter.com/miguelgrinberg">author</a> is also wrote the new
<a href="http://shop.oreilly.com/product/0636920031116.do">O'Reilly Flask Web Development</a>
book which is an excellent learning resource.</p>
<ul>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-i-hello-world">Part 1: Hello World</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-ii-templates">Part 2: Templates</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-iii-web-forms">Part 3: Web Forms</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-iv-database">Part 4: Database</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-v-user-logins">Part 5: User Logins</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-vi-profile-page-and-avatars">Part 6: Profile Page and Avatars</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-vii-unit-testing">Part 7: Unit Testing</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-viii-followers-contacts-and-friends">Part 8: Followers, Contacts, and Friends</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-ix-pagination">Part 9: Pagination</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-x-full-text-search">Part 10: Full Text Search</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xi-email-support">Part 11: Email Support</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xii-facelift">Part 12: Facelift</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xiii-dates-and-times">Part 13: Dates and Times</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xiv-i18n-and-l10n">Part 14: I18n and L10n</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xv-ajax">Part 15: Ajax</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xvi-debugging-testing-and-profiling">Part 16: Debugging, Testing and Profiling</a></li>
<li><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xvii-deployment-on-linux-even-on-the-raspberry-pi">Part 17: Deployment on Linux</a></li>
<li>
<p><a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xviii-deployment-on-the-heroku-cloud">Part 18: Deployment on the Heroku Cloud</a></p>
</li>
<li>
<p><a href="http://blog.john.mayonvolcanosoftware.com/building-a-blog-using-flask-and-angularjs-part-1/">Building a blog using Flask and AngularJS Part 1</a>
is the first of a multipart series on working with Flask and an AngularJS
front end.
<a href="http://blog.john.mayonvolcanosoftware.com/building-a-blog-using-flask-and-angularjs-part-2/">Part 2</a> is also available
<a href="https://github.com/basco-johnkevin/building-a-blog-using-flask-and-angularjs">along with the source code</a>.</p>
</li>
<li>
<p><a href="http://flask.pocoo.org/extensions/">The Flask Extensions Registry</a> is a
curated list of the best packages that extend Flask. It's the first location
to look through when you're wondering how to do something that's not in the
core framework.</p>
</li>
<li>
<p><a href="http://exploreflask.com/">Explore Flask</a> is a public domain book that
was previously backed on Kickstarter and cost money for about a year before
being open sourced. The book explains best practices and patterns for
building Flask apps.</p>
</li>
<li>
<p>Randall Degges wrote a detailed walkthrough for
<a href="https://stormpath.com/blog/build-a-flask-app-in-30-minutes/">building a Flask app in 30 minutes</a>.</p>
</li>
<li>
<p>Nice post by Jeff Knupp on <a href="http://www.jeffknupp.com/blog/2014/01/29/productionizing-a-flask-application/">Productionizing a Flask App</a>.</p>
</li>
<li>
<p><a href="http://maximebf.com/blog/2012/10/building-websites-in-python-with-flask/#.U06EZ-ZdW4J">Building Websites in Python with Flask</a>
is another walkthrough tutorial from first steps through
<a href="http://maximebf.com/blog/2012/11/getting-bigger-with-flask/">getting bigger with Flask</a>.</p>
</li>
<li>
<p>The Plank & Whittle blog has two posts, one on
<a href="http://www.plankandwhittle.com/packaging-a-flask-web-app/">Packaging a Flask web app</a>
and another on
<a href="http://www.plankandwhittle.com/packaging-a-flask-app-in-a-debian-package/">Packaging a Flask app in a Debian package</a>
once you've built an app and want to deploy it.</p>
</li>
<li>
<p>The Tuts+ <a href="http://code.tutsplus.com/tutorials/an-introduction-to-pythons-flask-framework--net-28822">Flask tutorial</a>
is another great walkthrough for getting started with the framework.</p>
</li>
<li>
<p><a href="http://readwrite.com/2014/07/11/one-click-messaging-app">Create Your Own Obnoxiously Simple Messaging App Just Like Yo</a>
is a silly walkthrough of very basic Flask web application that uses
<a href="https://www.nitrous.io/">Nitrous.io</a> to get started and
<a href="https://www.twilio.com/">Twilio</a> for SMS.</p>
</li>
<li>
<p><a href="http://www.realpython.com/blog/python/flask-by-example-part-1-project-setup/">Flask by Example: Part 1</a>
shows the basic first steps for setting up a Flask project.
<a href="http://www.realpython.com/blog/flask-by-example-part-2-postgres-sqlalchemy-and-alembic/">Part 2</a>
is also now online that shows how to use PostgreSQL, SQLAlchemy and Alembic.</p>
</li>
<li>
<p><a href="https://www.digitalocean.com/community/articles/how-to-structure-large-flask-applications">How to Structure Large Flask Applications</a>
covers a subject that comes up quickly once you begin adding significant
functionality to your Flask application.</p>
</li>
<li>
<p>"<a href="https://medium.com/@5hreyans/the-one-weird-trick-that-cut-our-flask-page-load-time-by-70-87145335f679">One line of code cut our Flask page load times by 60%</a>
is an important note about optimizing Flask template cache size to
dramatically increase performance in some cases.</p>
</li>
<li>
<p><a href="https://www.twilio.com/blog/2014/03/unit-testing-your-twilio-app-using-pythons-flask-and-nose.html">Unit Testing Your Twilio App Using Python’s Flask and Nose</a>
covers integrating the Twilio API into a Flask application and how to test
that functionality with <a href="https://nose.readthedocs.org/en/latest/">nose</a>.</p>
</li>
<li>
<p>The Flask documentation has some quick examples for how to deploy Flask
with
<a href="http://flask.pocoo.org/docs/deploying/wsgi-standalone/">standalone WSGI containers</a>.</p>
</li>
</ul>
<h2>Open source Flask example projects</h2>
<ul>
<li>
<p><a href="https://github.com/miguelgrinberg/microblog">Microblog</a> is the companion
open source project that goes along with Miguel Grinberg's O'Reilly Flask
book.</p>
</li>
<li>
<p><a href="https://github.com/JackStouffer/Flask-Foundation">Flask Foundation</a> is a
starting point for new Flask projects.</p>
</li>
<li>
<p><a href="https://github.com/sloria/cookiecutter-flask">Cookiecutter Flask</a> is a project
template for use with <a href="https://github.com/audreyr/cookiecutter">Cookiecutter</a>.</p>
</li>
<li>
<p><a href="https://github.com/mjhea0/flaskr-tdd">Flaskr TDD</a> takes the official Flask
tutorial and adds test driven development and JQuery to the project. </p>
</li>
<li>
<p>Use the <a href="https://github.com/kamalgill/flask-appengine-template">Flask App Engine Template</a>
for getting set up on Google App Engine with Flask.</p>
</li>
<li>
<p>Here is a
<a href="http://charlesleifer.com/blog/saturday-morning-hack-a-little-note-taking-app-with-flask/">note-taking app</a>
along with the
<a href="https://gist.github.com/coleifer/632d3c9aa6b2ea519384">source code in Gists</a>.</p>
</li>
<li>
<p><a href="https://github.com/BouncyNudibranch/bean-counter">Bean Counter</a> is an
open source Flask app for tracking coffee.</p>
</li>
</ul>
<h2>Flask framework learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
<a href="http://flask.pocoo.org/docs/installation/">Install Flask</a> on
your local development machine.</p>
<p><i class="fa fa-check-square-o"></i>
Work through the 18-part Flask tutorial listed first under "Flask resources"
below.</p>
<p><i class="fa fa-check-square-o"></i>
Read through <a href="http://flask.pocoo.org/extensions/">Flask Extensions Registry</a>
to find out what extensions you'll need to build your project.</p>
<p><i class="fa fa-check-square-o"></i>
Start coding your Flask app based on what you learned from the 18 part
Flask tutorial plus open source example applications found below. </p>
<p><i class="fa fa-check-square-o"></i>
Move on to the <a href="/deployment.html">deployment section</a> to get your initial
Flask project on the web.</p>
<h3>What do you need to learn about web frameworks next?</h3>
<h1>Bottle</h1>
<p><a href="http://bottlepy.org/docs/dev/index.html">Bottle</a> is a WSGI-compliant
<a href="https://github.com/defnull/bottle/blob/master/bottle.py">single source file</a>
web framework with no external dependencies except for the standard library
included with Python.</p>
<h2>Bottle resources</h2>
<ul>
<li>
<p>The <a href="http://bottlepy.org/docs/dev/tutorial.html">official Bottle tutorial</a>
provides a thorough view of basic concepts and features for the framework.</p>
</li>
<li>
<p>Digital Ocean provides an extensive <a href="https://www.digitalocean.com/community/articles/how-to-use-the-bottle-micro-framework-to-develop-python-web-apps">introductory post on Bottle</a>.</p>
</li>
<li>
<p>This tutorial provides a walkthrough for
<a href="http://www.giantflyingsaucer.com/blog/?p=3598">getting started with Bottle</a>.</p>
</li>
<li>
<p>Here's a short code snippet for
<a href="http://myadventuresincoding.wordpress.com/2011/01/02/creating-a-rest-api-in-python-using-bottle-and-mongodb/">creating a RESTful API with Bottle and MongoDB</a>.</p>
</li>
<li>
<p>This <a href="http://gotofritz.net/blog/weekly-challenge/restful-python-api-bottle/">tutorial</a>
is another Bottle walkthrough for creating a RESTful web API.</p>
</li>
<li>
<p><a href="http://gengo.github.io/decanter/">Decanter</a> is a library for structuring
Bottle projects.</p>
</li>
</ul>
<h2>Open source Bottle example projects</h2>
<ul>
<li><a href="https://github.com/thekad/pasttle">Pattle</a> is a pastebin clone built with
Bottle.</li>
</ul>
<h2>Bottle framework learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
<a href="https://github.com/defnull/bottle/raw/master/bottle.py">Download Bottle</a> or
install via pip with <code>pip install bottle</code> on your local development machine.</p>
<p><i class="fa fa-check-square-o"></i>
Work through the official
<a href="http://bottlepy.org/docs/dev/tutorial.html">Bottle tutorial</a>.</p>
<p><i class="fa fa-check-square-o"></i>
Start coding your Bottle app based on what you learned in the official
tutorial plus reading open source example applications found below. </p>
<p><i class="fa fa-check-square-o"></i>
Move on to the <a href="/deployment.html">deployment section</a> to get your initial
Bottle application on the web.</p>
<h3>What do you need to learn next?</h3>
<h1>Other Web Frameworks</h1>
<p>Python has a significant number of web frameworks outside the usual Django,
Flask and Bottle suspects.</p>
<h2>Pyramid</h2>
<p>The <a href="http://www.pylonsproject.org/">Pyramid framework</a> stems from the Pylons
project which develops a set of open source web application frameworks.
Pyramid applications are built using a model-view-controller architecture.</p>
<h2>Falcon</h2>
<p><a href="http://falconframework.org/">Falcon</a> is a minimalist web framework designed
with web application speed as a top priority.</p>
<h2>Morepath</h2>
<p><a href="http://morepath.readthedocs.org/en/latest/">Morepath</a> is a micro web
framework that routes URLs directly to model code.</p>
<ul>
<li>Morepath's creator gave a
<a href="https://www.youtube.com/watch?v=gyDKMAWPyuY">great talk on the motivation and structure for the new framework</a>
at EuroPython 2014.</li>
</ul>
<h2>web.py</h2>
<p><a href="http://webpy.org/">web.py</a> is a Python web framework designed for simplicity
in building web applications.</p>
<h2>web2py</h2>
<p><a href="http://www.web2py.com/">Web2py</a> is a batteries-included philosophy framework
with project structure based on model-view-controller patterns.</p>
<h2>Other web framework resources</h2>
<ul>
<li>
<p>This <a href="http://codecondo.com/14-minimal-web-frameworks-for-python/">roundup of 14 minimal Python frameworks</a>
contains both familiar and less known Python libraries.</p>
</li>
<li>
<p>The <a href="http://www.slideshare.net/r1chardj0n3s/web-microframework-battle/">web micro-framework battle</a>
presentation goes over Bottle, Flask, and many other lesser known Python
web frameworks.</p>
</li>
<li>
<p>A Python newcomer asked the Python Subreddit to
<a href="http://www.reddit.com/r/Python/comments/28qr7c/can_anyone_explain_the_differences_between_web2py/">explain the differences between numerous Python web frameworks</a>
and received some interesting responses from other users.</p>
</li>
</ul>
<h2>Other frameworks learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
Read through the web frameworks listed above and check out their project
websites. </p>
<p><i class="fa fa-check-square-o"></i>
It's useful to know what other web frameworks exist besides Django and Flask.
However, when you're just starting to learn to program there are significantly
more tutorials and resources for <a href="/django.html">Django</a> and
<a href="/flask.html">Flask</a> on the web. My recommendation is to start with one of
those two frameworks then expand your knowledge from there.</p>
<h3>What do you need to learn next?</h3>
<h1>Deployment</h1>
<p>Deployment involves packaging up your web application and putting it in a
production environment that can run the app.</p>
<h2>Why is deployment necessary?</h2>
<p>Your web application must live somewhere other than your own desktop or
laptop. A production environment is the canonical version of your current
application and its associated data.</p>
<h2>Deployment topics map</h2>
<p>Python web application deployments are comprised of many pieces that need to
be individually configured. Here is a map that visually depicts how each
deployment topic relates to each other. Click the image to pull up a PDF
version.</p>
<p><a href="/full-stack-python-map.pdf" target="_blank" style="border: none;"><img src="theme/img/full-stack-python-map.png" width="100%" alt="Full Stack Python site map." class="technical-diagram" /></a></p>
<h2>Deployment hosting options</h2>
<p>There are four options for deploying and hosting a web application:</p>
<ol>
<li>
<p><a href="/servers.html">"Bare metal" servers</a></p>
</li>
<li>
<p><a href="/servers.html">Virtualized servers</a></p>
</li>
<li>
<p><a href="/servers.html">Infrastructure-as-a-service</a></p>
</li>
<li>
<p><a href="/platform-as-a-service.html">Platform-as-a-service</a></p>
</li>
</ol>
<p>The first three options are similar. The deployer needs to provision one or
more servers with a Linux distribution. System packages, a web server,
WSGI server, database and the Python environment are then installed. Finally
the application can be pulled from source and installed in the environment.</p>
<p>Note that there are other ways of installing a Python web application through
system-specific package management systems. We won't cover those in this
guide as they are considered advanced deployment techniques.</p>
<h2>Deployment resources</h2>
<ul>
<li>
<p><a href="http://omniti.com/seeds/thoughts-on-web-application-deployment">Thoughts on web application deployment</a>
walks through stages of deployment with source control, planning,
continuous deployment and monitoring the results.</p>
</li>
<li>
<p><a href="http://blogs.atlassian.com/2014/04/practical-continuous-deployment/">Practical continuous deployment</a>
defines delivery versus deployment and walks through a continuous deployment
workflow.</p>
</li>
</ul>
<h2>Deployment learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
If you're tight on time look at the
<a href="/platform-as-a-service.html">platform-as-a-service (PaaS)</a> options. You can
deploy a low traffic project web app for free or low cost. You won't have to
worry about setting up the operating system and web server compared to going
the traditional server route. In theory you should be able to get your
application live on the web sooner with PaaS hosting.</p>
<p><i class="fa fa-check-square-o"></i>
<a href="/servers.html">Traditional server options</a> are your best bet for learning
how the entire Python web stack works. You'll often save money with a virtual
private server instead of a platform-as-a-service as you scale up.</p>
<p><i class="fa fa-check-square-o"></i>
Read about servers, <a href="/operating-systems.html">operating systems</a>,
<a href="/web-servers.html">web servers</a> and <a href="/wsgi-servers.html">WSGI servers</a> to get
a broad picture of what components need to be set up to run a Python web
application.</p>
<h3>How would you like to deploy your web app?</h3>
<h1>Servers</h1>
<p>Servers are the physical infrastructure to run all the layers of software
so your web application can respond to requests from clients such as web
browsers.</p>
<h2>Why are servers necessary?</h2>
<p>Your web application must live somewhere other than your own desktop or
laptop. Servers should ideally be accessible 24 hours a day, 7 days a week,
with no unplanned downtime. The servers that host your web application for
actual users (as opposed to test users) are known as <em>production</em> servers.
Production servers hold real data (again as opposed to test data) and must be
secure against unauthorized access.</p>
<h2>"Bare metal" servers</h2>
<p>The term <em>bare metal</em> refers to purchasing the actual hardware and hooking
it up to the Internet either through a business-class internet service
provider (ISP) or
<a href="http://webdesign.about.com/od/colocation/a/what_colocation.htm">co-locating the server</a>
with other servers. A "business-class" ISP is necessary because
most residential Internet service agreements explicitly prohibit running
web servers on their networks. You may be able to get away with low traffic
volume but if your site serves a lot of traffic it will alert an ISP's
filters.</p>
<p>The bare metal option offers the most control over the server configuration,
usually has the highest performance for the price, but also is the most
expensive upfront option and the highest ongoing maintenance. With bare
metal servers the ongoing operating cost is the electricity the server(s)
use as well as handling repairs when server components malfunction. You're
taking on manual labor working with hardware as well as the rest of the
software stack.</p>
<p>Buy actual hardware from a vendor either pre-built or as a collection of
components that you assemble yourself. You can also buy
pre-configured servers from Dell or HP. Those servers tend to be in
smaller case form factors (called "blades") but are correspondingly more
expensive than putting off-the-shelf components together yourself in a
standard computer case.</p>
<h2>Virtualized servers</h2>
<p>Virtual private servers (VPSs) are slices of hardware on top of a larger
bare metal server. Virtualization software such as
<a href="http://www.xen.org/">Xen</a> and
<a href="http://www.vmware.com/virtualization/what-is-virtualization.html">VMWare</a>
allow providers such as <a href="http://www.linode.com/">Linode</a> and
<a href="http://prgmr.com/xen/">prgmr</a> (as well as a many others) to provide
fractions of a full server that appear as their own instances. For example,
a server with an 8-core Xeon processor and 16 gigabytes of memory can be
sliced into 8 pieces with the equivalent of 1-core and 2 gigabytes of
memory.</p>
<p>The primary disadvantage of virtualized servers is that there is resource
overhead in the virtualization process. In addition, physical constraints
such as heavy I/O operations by a single virtualized instance on persistent
storage can cause performance bottlenecks for other virtualized instances on
the shared server. Choosing virtualized server hosting should be based on
your needs for urgency of service ticket requests and the frequency you
require for ongoing maintenance such as persistent storage backups.</p>
<h3>Virtualized servers resources</h3>
<ul>
<li>
<p><a href="http://blog.redfern.me/choosing-a-low-cost-vps/">Choosing a low cost VPS</a>
reviews the factors that you should weigh when deciding on hosting
providers.</p>
</li>
<li>
<p>This post covers hosting types and host to
<a href="http://www.purefiremedia.com/choose-a-web-host/">choose a web host</a>.</p>
</li>
</ul>
<h2>Infrastructure-as-a-service</h2>
<p>Infrastructure-as-a-service (IaaS) overlaps with virtualized servers
because the resources are often presented in the same way. The
difference between virtualized servers and IaaS is the granularity of the
billing cycle. IaaS generally encourages a finer granularity based on minutes
or hours of server usage instead of on monthly billing cycles.</p>
<p>IaaS can be used in combination with virtualized servers to provide
dynamic upscaling for heavy traffic. When traffic is low then virtualized
servers can solely be used. This combination of resources reduces cost at
the expense of greater complexity in the dynamically scaled infrastructure. </p>
<p>The most common IaaS platforms are
<a href="http://aws.amazon.com/">Amazon Web Services</a> and
<a href="http://www.rackspace.com/cloud/">Rackspace Cloud</a>.</p>
<p>The disadvantage to IaaS platforms is the lock-in if you have to write
custom code to deploy, dynamically scale, and generally understand your
infrastructure. Every platform has its quirks. For example,
Amazon's standard <a href="http://aws.amazon.com/ebs/">Elastic Block Store</a> storage
infrastructure has at least an order of magnitude worse I/O throughput
than working with your local disk. Your application's database queries may
work great locally but then when you deploy the performance is inadequate.
Amazon has <a href="http://aws.amazon.com/about-aws/whats-new/2012/07/31/announcing-provisioned-iops-for-amazon-ebs/">higher throughput EBS instances</a>
but you will pay correspondingly more for them. EBS throughput is just
one of many quirks you need to understand before committing to an
IaaS platform.</p>
<h3>Infrastructure-as-a-service resources</h3>
<ul>
<li>
<p><a href="http://www.screamingatmyscreen.com/2012/12/the-cloud-vs-dedicated-servers/">The cloud versus dedicated servers</a></p>
</li>
<li>
<p><a href="https://www.digitalocean.com/community/articles/5-common-server-setups-for-your-web-application">5 common server setups for your web application</a>
is a great introduction to how hosting can be arranged.</p>
</li>
<li>
<p><a href="http://libcloud.apache.org/">Apache Libcloud</a> is a Python library that
provides a unified API for many cloud service providers.</p>
</li>
<li>
<p><a href="http://aws.amazon.com/python/">Amazon Web Services has official documentation</a> for running Python web applications.</p>
</li>
<li>
<p><a href="https://github.com/boto/boto">boto</a> is an extensive and well-tested
Python library for working with Amazon Web Services.</p>
</li>
<li>
<p>Rackspace also has <a href="http://docs.rackspace.com/sdks/guide/content/python.html">official documentation for Python</a>.</p>
</li>
<li>
<p><a href="http://feross.org/how-to-setup-your-linode/">How to set up your Linode for maximum awesomeness</a>
shows how to work with a VPS once you've got the server up and running.</p>
</li>
</ul>
<h2>Servers learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
Sign up for a hosting provider. I recommend getting a
<a href="https://www.linode.com/?r=bfeecaf55a83cd3dd224a5f2a3a001fdf95d4c3d">Linode VPS</a>
to set up your initial infrastructure and deploy your web application there.
<a href="https://www.digitalocean.com/">Digital Ocean</a> and
<a href="http://prgmr.com/xen/">prgrmr</a> are other VPS options. You can change
hosting providers later after the deployment process is automated.</p>
<p><i class="fa fa-check-square-o"></i>
Provision your first server. It will be ready but in a shutdown state while
awaiting your instructions.</p>
<p><i class="fa fa-check-square-o"></i>
Move to the <a href="/operating-systems.html">operating systems</a> section to learn
how to load Ubuntu 12.04 LTS as a base OS for Python web applications.</p>
<h3>Keep going with setting up a server or try a PaaS?</h3>
<h1>Platform-as-a-service</h1>
<p>A platform-as-a-service (PaaS) provides infrastructure and a software layer
on which a web application is deployed. Running your web application from
a PaaS removes the need to know as much about the underlying servers,
operating system, web server, and often the WSGI server. </p>
<p><em>Note</em>: If you are not interested in deploying to a PaaS you can move
ahead to the <a href="../wsgi-servers.html">WSGI servers</a> section.</p>
<p>The PaaS layer defines how the application accesses resources such as
computing time, files, and external services. The PaaS provides a
higher-level abstraction for working with computing resources than deploying
an application to a server or IaaS.</p>
<p>A PaaS makes deployment and operations easier because it forces the developer
to conform applications to the PaaS architecture. For example, Heroku looks
for Python's requirements.txt file in the base directory of the repository
during deployment because that is the file's de facto community standard
location.</p>
<p><img src="theme/img/servers-versus-paas.png" width="100%" alt="Traditional LAMP server stack versus a Platform-as-a-Service stack" class="technical-diagram" /></p>
<p>If you go the PaaS route, you can skip configuring an operating system
and web server prebaked into PaaS offerings. PaaS offerings generally start
at the WSGI server layer. </p>
<h2>Platform-as-a-service responsibilities</h2>
<p>Although PaaS offerings simplify setting up and maintaining the servers,
operating system, and web server, developers still have responsibilities for other
layers of their web stack.</p>
<p>While it's useful to know the operating system that underpins your PaaS, for
example Heroku uses Ubuntu 10.04, you will not have to know as much about
securing the operating system and server level. However, web applications deployed
to a PaaS are just as vulnerable to security breaches at the application level
as a standard LAMP stack. It's still your responsibility to ensure the web
application framework and your app itself is up to date and secured. See the
<a href="../web-application-security.html">security section</a> for further information.</p>
<h2>Platforms-as-a-service that support Python</h2>
<ul>
<li>
<p><a href="http://www.heroku.com/">Heroku</a></p>
</li>
<li>
<p><a href="https://developers.google.com/appengine/">Google App Engine</a></p>
</li>
<li>
<p><a href="https://gondor.io/">Gondor</a></p>
</li>
<li>
<p><a href="https://www.pythonanywhere.com/">PythonAnywhere</a></p>
</li>
<li>
<p><a href="https://openshift.redhat.com/community/get-started/python>">OpenShift</a></p>
</li>
<li>
<p><a href="https://aws.amazon.com/elasticbeanstalk/">AWS Elastic Beanstalk</a></p>
</li>
</ul>
<h2>Platform-as-a-service resources</h2>
<ul>
<li>
<p><a href="http://appsembler.com/blog/paas-bakeoff-comparing-stackato-openshift-dotcloud-and-heroku-for-django-hosting-and-deployment/">PaaS bakeoff: Comparing Stackato, OpenShift, Dotcloud and Heroku for Django hosting and deployment</a> by <a href="https://twitter.com/natea">Nate Aune</a>.</p>
</li>
<li>
<p><a href="http://www.deploydjango.com/">Deploying Django</a> by Randall Degges is
another great free resource about Heroku.</p>
</li>
<li>
<p>Heroku's
<a href="https://devcenter.heroku.com/articles/getting-started-with-python">Python deployment documentation</a>
provides clear examples for how to work with virtualenv, pip and
requirementst.txt to get a applications deployed to their platform.</p>
</li>
<li>
<p>Miguel Grinberg's Flask tutorial contains an entire post on deploying
<a href="http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xviii-deployment-on-the-heroku-cloud">Flask applications to Heroku</a>.</p>
</li>
<li>
<p>This series on DevOps Django by
<a href="https://twitter.com/rdegges">Randall Degges</a> is great reading for
using the Heroku service:</p>
<ul>
<li><a href="http://www.rdegges.com/devops-django-part-1-goals/">Part One: Goals</a></li>
<li><a href="http://www.rdegges.com/devops-django-part-2-the-pain-of-deployment/">Part Two: The Pain of Deployment</a></li>
<li><a href="http://www.rdegges.com/devops-django-part-3-the-heroku-way/">Part Three: The Heroku Way</a></li>
<li><a href="http://rdegges.com/devops-django-part-4-choosing-heroku">Part Four: Choosing Heroku</a></li>
</ul>
</li>
</ul>
<h2>Platform-as-a-service learning checklist</h2>
<p><i class="fa fa-check-square-o"></i>
Review the potential Python platform-as-a-service options above and on their
websites.</p>
<p><i class="fa fa-check-square-o"></i>
Sign up for a PaaS account at the provider that appears to best fit your
application needs. Heroku is the PaaS option recommended for starters due to
their detailed documentation and walkthroughs available on the web. However,
the other options are perfectly viable since their purpose is to make deploying
applications as easy as possible.</p>
<p><i class="fa fa-check-square-o"></i>
Check if there are any PaaS-specific configuration files needed for your app
to run properly on the PaaS after it is deployed.</p>
<p><i class="fa fa-check-square-o"></i>
Deploy your app to the PaaS. </p>
<p><i class="fa fa-check-square-o"></i>
Sync your application's configuration with the database.</p>
<p><i class="fa fa-check-square-o"></i>
Set up a content delivery network for your application's
<a href="/static-content.html">static content</a> unless your PaaS provider already
handles this deployment step for you.</p>
<p><i class="fa fa-check-square-o"></i>
Check if the application's functionality is working and tweak as necessary.</p>
<h3>Do you want to use a PaaS or deploy to a traditional server?</h3>
<h1>Operating Systems</h1>
<p>An operating system runs on the server or virtual server and controls access
to computing resources. The operating system also includes a way to install
programs necessary for running your Python web application.</p>
<h2>Why are operating systems necessary?</h2>
<p>An operating system makes many the computing tasks we take for granted easy.
For example, the operating system enables writing to files,
communicating over a network and running multiple programs at once.
Otherwise you'd need to control the CPU, memory, network, graphics card,
and many other components with your own low-level implemention.</p>
<p>Without using an existing operating system like Linux, Mac OS X, or Windows,
you'd be forced to write a new operating system as part of your web
application. It would be impossible to write features for your Python
web application because you'd be too busy hunting down a memory leak in
your assembly code, if you even were able to get that far.</p>
<p>Fortunately, the open source community provides Linux to the Python world
as a rock solid free operating system for running our applications.</p>
<h2>Recommended operating systems</h2>
<p>The only recommended operating system for production Python web stack
deployments is Linux. There are several Linux distributions commonly used
for running production servers. Ubuntu Long Term Support (LTS) releases,
Red Hat Enterprise Linux, and CentOS are all viable options. </p>
<p>Mac OS X is fine for development activities. Windows and Mac
OS X are not appropriate for production deployments unless there is a
major reason why you must use them in lieu of Linux.</p>
<h3>Ubuntu</h3>
<p>Ubuntu is a Linux distribution packaged by the
<a href="http://www.canonical.com/">Canonical Ltd</a> company. Ubuntu uses the
Debian distribution as a base for packages, including the
<a href="http://wiki.debian.org/Apt">aptitude package manager</a>. For desktop versions
of Ubuntu, GNOME (until the 11.04 release) or Unity (11.10 through current)
is bundled with the distribution to provide a user interface.</p>
<p>Ubuntu <a href="https://wiki.ubuntu.com/LTS">Long Term Support</a> (LTS) releases
are the recommended versions to use for deployments. LTS versions receive
five years of post-release updates from Canonical. Every two years, Canonical
creates a new LTS release, which allows for an easy upgrade path as well
as flexibility in skipping every other LTS release if necessary. As of
February 2014,
<a href="http://releases.ubuntu.com/precise/">12.04 Precise Pangolin</a>
is the latest Ubuntu LTS release.</p>
<h4>Ubuntu Python Packages</h4>
<p>There are several
<a href="https://help.ubuntu.com/12.04/serverguide/aptitude.html">Aptitude</a>
packages found on Linux servers running a Python stack. These packages are: </p>
<ul>
<li>
<p><a href="http://packages.ubuntu.com/precise/python-dev">python-dev</a> for header
files and static library for Python</p>
</li>
<li>
<p><a href="http://packages.ubuntu.com/precise/python-virtualenv">python-virtualenv</a>
for creating and managing Python
<a href="http://www.virtualenv.org/en/latest/">virtualenvs</a> to isolate library
dependencies</p>
</li>