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<!DOCTYPE html>

<title>Flask - Full Stack Python</title>

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<![endif]-->

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<body>

</a>

<span class="logo-title"><a href="/">Full Stack Python</a></span>

</div>

</div> <div class="row">

<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>.

<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>

</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-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://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://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.

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://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>

</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/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>

</ul>

<h2>Flask framework learning checklist</h2>

<a href="http://flask.pocoo.org/docs/installation/">Install Flask</a> on

your local development machine.</p>

Work through the 18-part Flask tutorial listed first under "Flask resources"

below.</p>

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>

Start coding your Flask app based on what you learned from the 18 part

Flask tutorial plus open source example applications found below. </p>

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>

How do I deploy Flask web application when it's ready to go live?

</p>

</div>

</a>

I'd like to go back to reviewing other web frameworks.

</p>

</div>

The user interface looks terrible. How do I style my web app?

</p>

</div>

How can I version and store my source code so I don't lose it?

</p>

</div>

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</div>

<div class="panel-heading"><h3 class="panel-head">Flask</h3></div>

<a href="/">Full Stack Python</a> is an open book that explains

each Python web application stack layer and provides the

best web resources for those topics.

<hr/>

Need more detailed tutorials and walkthroughs than what is

presented here?

<a href="/email.html">Sign up for an email alert when that content is created.</a>

<hr/>

<a href="http://twitter.com/mattmakai">Matt Makai</a> built

this site with assistance from community pull requests. On GitHub

you can <a href="https://github.com/makaimc">follow Matt</a>

to see the daily changes.

</div>

<h3 class="panel-head">Table of Contents</h3>

</div>

<a href="/introduction.html" class="list-group-item smaller-item ">Introduction</a>

<a href="/web-frameworks.html" class="list-group-item smaller-item ">Web Frameworks</a>

<a href="/django.html" class="list-group-item smaller-item ">Django</a>

<a href="/flask.html" class="list-group-item smaller-item active">Flask</a>

<a href="/bottle.html" class="list-group-item smaller-item ">Bottle</a>

<a href="/other-web-frameworks.html" class="list-group-item smaller-item ">Other Web Frameworks</a>

<a href="/deployment.html" class="list-group-item smaller-item ">Deployment</a>

<a href="/servers.html" class="list-group-item smaller-item ">Servers</a>

<a href="/operating-systems.html" class="list-group-item smaller-item ">Operating Systems</a>

<a href="/web-servers.html" class="list-group-item smaller-item ">Web Servers</a>

<a href="/platform-as-a-service.html" class="list-group-item smaller-item ">Platform-as-a-service</a>

<a href="/wsgi-servers.html" class="list-group-item smaller-item ">WSGI Servers</a>

<a href="/source-control.html" class="list-group-item smaller-item ">Source Control</a>

<a href="/application-dependencies.html" class="list-group-item smaller-item ">Application Dependencies</a>

<a href="/configuration-management.html" class="list-group-item smaller-item ">Configuration Management</a>

<a href="/databases.html" class="list-group-item smaller-item ">Databases</a>

<a href="/no-sql-datastore.html" class="list-group-item smaller-item ">NoSQL Data Stores</a>

<a href="/cascading-style-sheets.html" class="list-group-item smaller-item ">Cascading Style Sheets</a>

<a href="/javascript.html" class="list-group-item smaller-item ">JavaScript</a>

<a href="/application-programming-interfaces.html" class="list-group-item smaller-item ">Application Programming Interfaces</a>

<a href="/api-integration.html" class="list-group-item smaller-item ">API Integration</a>

<a href="/api-creation.html" class="list-group-item smaller-item ">API Creation</a>

<a href="/static-content.html" class="list-group-item smaller-item ">Static Content</a>

<a href="/caching.html" class="list-group-item smaller-item ">Caching</a>

<a href="/task-queues.html" class="list-group-item smaller-item ">Task Queues</a>

<a href="/logging.html" class="list-group-item smaller-item ">Logging</a>

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<a href="http://www.mattmakai.com/" class="underline">Matt Makai</a>

2014

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