Django
[un(-)chained]

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#python2.7

virtualenv env
source env/bin/activate
pip install -r requirements.txt

Linux machines

source env/bin/activate
cd /to/the/project/directory
django-admin.py startproject journalclub

Your directory structure will be something like this

Let's make some changes

change ALLOWED_HOSTS = [] to ALLOWED_HOSTS = ['*']

vim journalclub/settings.py

To create a database for our site, let's run the following in the console

python manage.py migrate

Now we can start the web server by running

python manage.py runserver 0:8001

http://127.0.0.1:8001/

Application

We will create a separate application inside our project

python manage.py startapp blogs

POST
title
description
author
created_date
published_date

Model


from django.db import models
from django.utils import timezone


class Post(models.Model):
    author = models.ForeignKey('auth.User')
    title = models.CharField(max_length=200)
    description = models.TextField()
    created_date = models.DateTimeField(default=timezone.now)
    published_date = models.DateTimeField(blank=True, null=True)

    def publish(self):
        self.published_date = timezone.now()
        self.save()

    def __str__(self):
        return self.title

vim journalclub/settings.py

# add blogs to the installed apps

The final step here is to add our new model to our database
First we have to make Django know that we have some changes in our model. (In this case we have just created it!)
Go to the console and type the following

python manage.py makemigrations blogs

Django prepared a migration file for us that we now have to apply to our database
Now type the following

python manage.py migrate blogs

Hurray! Our Post model is now in our database!
How do i see it?

python manage.py dbshell

# in the sqlite shell
sqlite> .tables

# to see the column names of a table
sqlite> PRAGMA table_info(blogs_post);

# to quit
sqlite>.quit

sudo apt-get  install  sqlite3

Okay so far we have created a application and it's model
Now that we have a DB to store our posts, how do we actually store values in the table?
Lets type the following in our console, which will launch an interactive shell

python manage.py shell

from blog.models import Post
Post.objects.all()
Post.objects.create(author='ambi', title='Sample title',\
        description='Test')

How do we query our table and populate values?

from django.contrib.auth.models import User
User.objects.all()
User.objects.create_user(username='test',\
        email='ambi@madstreetden.com',\
        password='test')

me = User.objects.get(username='ambi')
Post.objects.create(author=me,\
        title='Sample title',\
        description='Test')

We have created multiple posts
Now lets publish one

post = Post.objects.get(title="Sample title")
post.publish()
Post.objects.filter(published_date__lte=timezone.now())

Post.objects.filter(published_date__lte=timezone.now())
Post.objects.filter(published_date__lte=timezone.now()).order_by('published_date')
Post.objects.filter(published_date__lte=timezone.now()).order_by('created_date')

Ordering and chaining query sets

Lets exit the interactive shell

URLs

Lets take a look at journalclub/urls.py

from django.conf.urls import include

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'', include('blogs.urls')),
]

Lets create a urls.py in the blogs app

from django.conf.urls import url
from . import views

urlpatterns = [
    url(r'^$', views.post_list, name='post_list'),
]

Now lets run the server again

Views

Go into the blogs application and open views.py

from django.http import JsonResponse


def post_list(request):
    return JsonResponse({'status': 'okay', 'message': 'pong'},
            status=200)

But wait this is not what i want

from .models import Post

def post_list(request):
    data = Post.objects.all()
    fd = []
    for x in data:
        tmp = {}
        tmp['title'] = x.title
        tmp['author'] = x.author.username
        fd.append(tmp)
    return JsonResponse({'status': 'okay', 'message': fd},
            status=200)

Sending parameters in your HTTP request

from django.contrib.auth.models import User
import traceback, json

def post_create(request):
    try:
        payload=json.loads(request.body)
        username=payload['username']
        title=payload['title']
        description=payload['description']
        me = User.objects.get(username=username)
        p=Post.objects.create(author=me, title=title, description=description)
        return JsonResponse({'status': 'okay', 'message': '', 'data':{'post_id': p.id}},
                            status=200)
    except:
        err = traceback.format_exc()
        return JsonResponse({'status': 'okay', 'message': err},
                            status=500)

Adding the respective view to urls.py

Publishing a new post

def publish_post(request):
    try:
        payload=json.loads(request.body)
        post_id = payload['post_id']
        p = Post.objects.get(id=post_id)
        p.publish()
        return JsonResponse({'status': 'okay', 'message': 'Post published',\
                            'data':{'title':p.title}},
                            status=200)
    except:
        err = traceback.format_exc()
        return JsonResponse({'status': 'okay', 'message': err},
                            status=500)

Thank you

Templates

def post_list(request):
    data = Post.objects.all()
    fd = []
    for x in data:
        tmp = {}
        tmp['title'] = x.title
        tmp['author'] = x.author.username
        fd.append(tmp)
    #return JsonResponse({'status': 'okay', 'message': '', 'data':fd},
    #        status=200)
    #return render(request, 'blogs/post_list.html', {})
    return render(request, 'blogs/posts_list.html', {'posts': data})

cd applications/templates/applicationname/template.html

Now, Thank you for real

I mean really

Lets get back to work

Django unchained

By ambi

Django [un(-)chained]

Django unchained

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Django
[un(-)chained]