Extending the django girls tutorial

Ideas on how anyone that is using the excellent django girls tutorial can extend it. Presented to pybelfast on the 27th November 2017

Transcript

1. PYBELFAST / @SWMCC
   EXTENDING THE DJANGO GIRLS
   TUTORIAL
   

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2. ABOUT ME
   STEPHEN MCCULLOUGH - @SWMCC ON MOST THINGS
   ▸ Lead Software Engineer @ ShopKeep
   ▸ I help run several meetups:
   ▸ Pybelfast
   ▸ BelfastRuby
   ▸ BelfastElixir
   ▸ Previous job (MissionIQ) used Django exclusively
   

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3. PURPOSE OF THIS TALK
   EXTEND THE DJANGO GIRLS TUTORIAL
   ▸ At the time of writing there are four extensions:
   ▸ Add more to your website
   ▸ Extending the base built (filters, delete)
   ▸ Secure your website
   ▸ Adding authorisation
   ▸ Create a comment model
   ▸ Adding a new model
   ▸ PostgresSQL installation
   

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4. PURPOSE OF THIS TALK
   EXTEND THE DJANGO GIRLS TUTORIAL
   ▸ All perfectly acceptable
   ▸ The industry moves at a fast space
   ▸ If you aren’t evolving your skill set you will get left
   behind
   ▸ Two things stood out to me when reviewing the tutorials
   ▸ No testing
   ▸ No ‘services’ offered
   

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5. STEVIE, I CAN’T SELL TESTS,
   OK!!
   Former. Boss.
   WORST. QUOTE. OVER.
   

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6. TESTING
   TESTING IN PYTHON
   ▸ Django uses unittest
   ▸ You can use any library you want
   ▸ Its very important to add tests. It is the one true metric that
   separates a ‘good’ developer from a ‘bad’ one.
   ▸ Its not up for debate.
   ▸ Learn how to test your app in django. There are hundreds
   of pages on this subject.
   

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7. SERVICES
   SERVICES IN A DJANGO APP
   ▸ Becoming more and more ‘popular’ to offer services
   from an ‘app’ that django produces
   ▸ Serves out JSON to a consumer
   ▸ No HTML/CSS at the django end
   

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8. SERVICES
   CHOICES LOTS OF CHOICES…….
   ▸ Several choices can be made re: providing services in
   django:
   ▸ Decorators
   ▸ Django REST Framework
   ▸ Django Tastypie
   ▸ *BATTERIES NOT INCLUDED - GET USED TO IT!
   

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9. SERVICES
   DJANGO TASTY PIE
   ▸ django-admin start app services
   ▸ pip install django-tastypie
   ▸ Add “services” in the INSTALLED_APPS list ‘mysite/settings.py’
   INSTALLED_APPS = (
   'django.contrib.admin',
   'django.contrib.auth',
   'django.contrib.contenttypes',
   'django.contrib.sessions',
   'django.contrib.messages',
   ‘django.contrib.staticfiles',
   ‘blog’,
   'tastypie',
   'services'
   )
   

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10. SERVICES
    DJANGO-TASTYPIE
    ▸ We are going to authenticate our upcoming REST API using an API KEY.
    ▸ Tastypie has a builtin API Key gen.
    ▸ We use by adding a signal for the User object.
    ▸ When a user is created it will generate an API key.
    ▸ So create `services/apps.py`
    # services/apps.py
    from django.apps import AppConfig
    from django.contrib.auth.models import User
    from django.db.models import signals
    from tastypie.models import create_api_key
    class ServiceConfig(AppConfig):
    name = "services"
    def ready(self):
    signals.post_save.connect(create_api_key, sender=User)
    

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11. SERVICES
    DJANGO-TASTYPIE
    ▸ Now we need to do some magic in __init__.py
    # services/__init__.py
    default_app_config = ‘services.apps.ServiceConfig'
    ▸ This is a pretty basic step but very powerful. Now any new
    users have a generated API key.
    ▸
    

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12. SERVICES
    RESOURCES IN DJANGO-TASTYPIE
    ▸ Resources are the killer ‘thing’ in TastyPie
    ▸ Defining a resource will convert the model into an API Stream
    ▸ Allows us to validate requested data
    ▸ Modifying a response before sending onto a client
    # services/api.py
    from tastypie.resources import ModelResource
    from .models import Post
    class PostResource(ModelResource):
    class Meta:
    queryset = Post.objects.all()
    resource_name = 'post'
    allowed_methods = ['get']
    

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13. SERVICES
    CONSUMING THE API
    ▸ We need to let a client consume our API
    # services/urls.py
    from django.conf.urls import url, include
    from tastypie.api import Api
    from services.api import PostResource
    v1_api = Api(api_name='v1')
    v1_api.register(PostResource())
    urlpatterns = [url(r'^api/', include(v1_api.urls))]
    ▸ Include the URL in the project’s URL dispatcher. Note I took away the previous blog.url
    # mysite/urls.py
    from django.conf.urls import include, url
    from django.contrib import admin
    urlpatterns = [
    url(r'^admin/', include(admin.site.urls)),
    url(r'', include(“services.urls")),
    ]
    

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14. SERVICES
    CONSUMING THE API
    ▸ That’s it!
    ▸ Go to the url 

    http://localhost:8000/api/v1/posts/?format=json
    ▸ And you will see this:
    {
    "meta":{
    "limit":20,
    "next":null,
    "offset":0,
    "previous":null,
    "total_count":2
    },
    "objects":
    [
    {
    "id":1,
    “title”:”Django is great",
    “text”:”Paddy Sucks”,
    “author_id”:1,
    "resource_uri":"/api/v1/post/1/"
    },
    {
    "id":2,
    “name":"Rails is alright",
    “text”:”Paddy still sucks”,
    “author_id”:1,
    "resource_uri":"/api/v1/post/2/"
    },
    ]
    }
    

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15. FIN
    QUESTIONS?
    

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