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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">At the point at which the Horizon project first began (during the Cactus, I believe) the handful of folks working on it wanted a Python web framework that would
 get them up and running as fast as possible. That meant lots of built-in, “batteries-included” features so they didn’t need to reinvent a bunch of wheels; and that also meant something they had at least passing familiarity with. So they chose Django.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Speaking from personal opinion at this point (and as a former Horizon PTL and Django core developer): Flask is good for writing APIs or very simple sites, but
 not for large webapps. They would have had to write a ton of code for things other frameworks have built-in. And Pylons and Zope don’t have nearly the base of community, resources, or documentation that Django does. Twisted would have been another option,
 but the event-driven model of Twisted is hard for many people to wrap their heads around and wasn’t appropriate at the time.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">All things considered I think the choice of Django was relatively sound (I had nothing to do with the original choice). It’s allowed the project to grow and
 scale effectively over the last 3+ years.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">At this point, though, there’s a clear demand for a more responsive and real-time dashboard experience, and that generally means moving as much as possible
 into a client-side JavaScript-based webapp. That’s why the Horizon team has been making efforts to move towards things like angular.js and socket.io to help bring the next era of modern Horizon functionality. It’s not a simple or easy transition, but as that
 transition takes place a vast amount of the Django code will likely go away.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I hope that helps shed some light on the historical reason for “why Django” as well as why it may matter less that it was Django and not something else over
 time.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">All the best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Gabriel<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif"">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif""> Guillermo Alvarado [mailto:guillermoalvarado89@gmail.com]
<br>
<b>Sent:</b> Monday, August 18, 2014 4:20 PM<br>
<b>To:</b> openstack@lists.openstack.org<br>
<b>Subject:</b> [Openstack] Why Horizon use Django instead Flask or other?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hello,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I am wondering why Horizon is built in Django instead other Python Framework Like Pylons, Flask, Zope or oher ?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks for your time!<o:p></o:p></p>
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<p class="MsoNormal">~GA<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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