<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>

<p><a href="http://www.heroku.com/">Heroku</a></p>

<p><a href="https://developers.google.com/appengine/">Google App Engine</a></p>

<p><a href="https://gondor.io/">Gondor</a></p>

<p><a href="https://www.pythonanywhere.com/">PythonAnywhere</a></p>

<p><a href="https://openshift.redhat.com/community/get-started/python&gt;">OpenShift</a></p>

<p><a href="https://aws.amazon.com/elasticbeanstalk/">AWS Elastic Beanstalk</a></p>

<h2>Platform-as-a-service resources</h2>

<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>

<p><a href="http://www.deploydjango.com/">Deploying Django</a> by Randall Degges is

another great free resource about Heroku.</p>

<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>

<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>

<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>

<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>

<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>

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

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

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

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

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