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<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>

<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>

<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>

<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>

<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>

<p><a href="https://www.airpair.com/python/posts/django-flask-pyramid">Django vs Flask vs Pyramid: Choosing a Python Web Framework</a>

contains background information and code comparisons for similar

web applications built in these three big Python frameworks.</p>

<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>

<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>

<p><a href="http://www.reddit.com/r/webdev/comments/2les4x/what_frameworks_do_you_use_and_why_are_they/">What web frameworks do you use and why are they awesome?</a>

is a language agnostic Reddit discussion on web frameworks. It's interesting

to see what programmers in other languages like and dislike about their

suite of web frameworks compared to the main Python frameworks.</p>

<h2>Web frameworks learning checklist</h2>

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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>

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Work through a detailed tutorial found within the resources links on the

framework's page.</p>

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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>

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Tell me more about the Django framework.

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I want to learn more about the Flask web framework.

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Show me more information on Bottle.

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What other Python web frameworks exist?

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

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<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.

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

<a href="/web-frameworks.html" class="list-group-item smaller-item active">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 ">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="/platform-as-a-service.html" class="list-group-item smaller-item ">Platform-as-a-service</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="/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="/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="/web-design.html" class="list-group-item smaller-item ">Web Design</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="/continuous-integration.html" class="list-group-item smaller-item ">Continuous Integration</a>

<a href="/code-metrics.html" class="list-group-item smaller-item ">Code Metrics</a>

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

<a href="/monitoring.html" class="list-group-item smaller-item ">Monitoring</a>

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

<a href="/web-application-security.html" class="list-group-item smaller-item ">Web Application Security</a>

<a href="/best-python-resources.html" class="list-group-item smaller-item ">Best Python Resources</a>

<a href="/development-environments.html" class="list-group-item smaller-item ">Development Environments</a>

<a href="/about-author.html" class="list-group-item smaller-item ">About the Author</a>

<a href="/change-log.html" class="list-group-item smaller-item ">Change Log</a>

<a href="/future-directions.html" class="list-group-item smaller-item ">Future Directions</a>

<a href="/what-full-stack-means.html" class="list-group-item smaller-item ">What "Full Stack" Means</a>

<a href="/websockets.html" class="list-group-item smaller-item ">WebSockets</a>

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