A quick introduction to Django with tips on deploying to Heroku. Presented at TechCamp Memphis, Fall 2012

1. Django:
A Whirlwind Tour
Brad Montgomery
Email: brad@workforpie.com
Twitter: bkmontgomery
Friday, November 2, 12

2. Django: Features
• Python
• ORM: Object-Relational Mapper
• MVC-inspired (MVT)
• Clean URLs
• Huge Community
• Worlds Best Documentation
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3. Batteries Included
aka: contrib apps
• admin
• auth
• comments
• gis
• syndication (atom/rss feeds)
• sitemaps
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4. https://djangoproject.com/
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5. Community
• 3rd-party, open source apps
• django-registration
• django-social-auth
• django-taggit
• django-gravatar2
• django-relationships
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6. http://djangopackages.com/
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7. So, who’s actually using Django?
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8. Disqus,
Instagram,
Pintrest, Mozilla,
Rdio, Bitbucket,
Work for Pie,
GiantBomb,
The Onion
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9. Projects & Apps
• Projects are a collection of applications
• Settings
• DB Connections
• installed apps
• Filesystem paths
• Command-line tool: manage.py
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10. Projects & Apps
$ django-admin.py
startproject
sampleproject
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11. Projects & Apps
sampleproject/
!"" manage.py
#"" sampleproject
!"" __init__.py
!"" settings.py
!"" urls.py
#"" wsgi.py
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12. Projects & Apps
$ python manage.py
startapp blog
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13. Projects & Apps
sampleproject/
!"" blog
!"" __init__.py
!"" models.py
!"" tests.py
#"" views.py
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14. Models
from django.db import models
from django.contrib.auth.models import User
class Post(models.Model):
author = models.ForeignKey(User)
title = models.CharField(max_length=128)
slug = models.SlugField(max_length=128, unique=True)
content = models.TextField()
published_on = models.DateTimeField(auto_now_add=True)
sampleproject/blog/models.py
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15. syncdb
$ python manage.py syncdb
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16. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

17. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

18. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

19. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

20. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

21. Views
from django.shortcuts import render_to_response
from django.template import RequestContext
from models import Post
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

22. A base template
<!DOCTYPE html>
<html>
<head>
<title>
{% block title %}{% endblock %}
</title>
</head>
<body>
{% block content %}{% endblock %}
</body>
</html>
sampleproject/sampleproject/templates/base.html
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23. A base template
<!DOCTYPE html>
<html>
<head>
<title>
{% block title %}{% endblock %}
</title>
</head>
<body>
{% block content %}{% endblock %}
</body>
</html>
sampleproject/sampleproject/templates/base.html
Friday, November 2, 12

24. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

25. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

26. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

27. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

28. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

29. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

30. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

31. A post template
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

32. URL Conf’s
• Tie it all together!
• Route HTTP requests to views
• May also capture values
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33. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

34. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

35. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

36. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

37. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

38. Root URLConf
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

39. An HTTP Request
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40. An HTTP Request
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41. An HTTP Request
blog/sample-title/
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

42. An HTTP Request
blog/sample-title/
from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
url(r'^blog/(?P<post_slug>.+)/$',
'blog.views.display_post',
name='display_post'),
url(r'^admin/', include(admin.site.urls)),
)
sampleproject/sampleproject/urls.py
Friday, November 2, 12

43. An HTTP Request
sample-title
def display_post(request, post_slug):
post = Post.objects.get(slug=post_slug)
template_data = {'post': post}
template = "blog/post.html"
return render_to_response(
template,
template_data,
context_instance=RequestContext(request)
)
sampleproject/blog/views.py
Friday, November 2, 12

44. An HTTP Request
{% extends "base.html" %} Sample Title
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

45. An HTTP Request
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %} Lorem Ipsum...
{% block content %}
<h1>{{ post.title }}</h1>
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
Friday, November 2, 12

46. An HTTP Request
{% extends "base.html" %}
{% block title %}
{{ post.title }}
{% endblock %}
{% block content %}
<h1>{{ post.title }}</h1> Nov 3, 2012
{{ post.content|urlize|linebreaks }}
<p>Published on:
{{ post.published_on|date:"M d, Y" }}</p>
{% endblock %}
sampleproject/blog/templates/blog/post.html
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47. An HTTP Request
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48. Friday, November 2, 12

49. A Typical Stack
Linux
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50. A Typical Stack
PostgreSQL
Linux
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51. A Typical Stack
Gunicorn + Django
PostgreSQL
Linux
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52. A Typical Stack
nginx
Gunicorn + Django
PostgreSQL
Linux
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53. A Typical Stack
Varnish
Memcached
nginx
RabbitMQ
Gunicorn + Django
Redis
PostgreSQL
Linux
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54. Friday, November 2, 12

55. Enter: Heroku
• Deploy & Scale in the Cloud
• Provides on-demand App/DB servers
• The Heroku Toolbelt
• http://www.heroku.com/
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56. Deploying to Heroku
Do a little bit of setup...
$ heroku create
Creating app-name... done, stack is cedar
http://app-name.herokuapp.com/ | git@heroku.com:app-name.git
Git remote heroku added
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57. Deploying to Heroku
$ git push heroku master
... lots of output ...
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58. Deploying to Heroku
$ heroku run python manage.py syncdb
... your typical syncdb output ...
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59. Deploying to Heroku
Develop locally, then when you want
to deploy, just run:
$ git push heroku master
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60. Want to Learn More?
• Official Django Docs
• https://docs.djangoproject.com
• *Djangobook http://www.djangobook.com
• Find Apps: http://www.djangopackages.com/
• Coming Soon: http://gettingstartedwithdjango.com/
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61. Q.E.D.
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