Build a Blog with Django #1: Project Configuration

In this tutorial series, we are going to build a blog application with Python and the Django web framework. We will start from the configuration of the project then we will implement the following features: authentication, reset password, change password, comment, create a post, and finally we will deploy the application.

Dependencies

Python 3.8
Django 3.1
PostgreSQL 12.4
Ubuntu 20.04

To check the version of Python tap the following command in the terminal:

$ python3 -V
Python 3.8.2

Setting Up a Virtual Environment and the Project

Let’s start by creating a new directory and then initialize a virtual environment:

$ mkdir myproject && cd $_
myproject$ python3 -m venv venv 
myproject$ source venv/bin/activate

Note: From now on when we are in the root directory of the project (myproject$), I will abbreviate it to $.

Now we can install Django with the pip command:

(venv) $ pip install django

When the installation ends we are ready to create a new Django project:

(venv) $ django-admin startproject blog .

The use of . just tell Django to create the project in the current directory (myproject).

Configuring a PostgreSQL Database

To use a PostgreSQL database in a Django project, you must install the Psycopg2 library:

(venv) $ pip install psycopg2

Now we need to connect to PostgreSQL using the postgres user to create a user and a database:

(venv) $ sudo -u postgres psql
password for user postgres : 
psql (12.4 (Ubuntu 12.4-1.pgdg20.04+1))
Type "help" for help.

postgres=# CREATE DATABASE blog;
postgres=# CREATE USER test WITH ENCRYPTED PASSWORD '1234';
postgres=# GRANT ALL PRIVILEGES ON DATABASE blog TO test;
postgres=# \q

The last step is to let Django know that we want to use the database we just created.

# blog/settings.py
# ...

DATABASES = {
  'default': {
      'ENGINE': 'django.db.backends.postgresql',
      'NAME': 'blog',
      'USER': 'test',
      'PASSWORD': '1234',
      'HOST': '',
      'PORT': 5432
  }
}

# ...

You can remove the db.sqlite3 database:

(venv) $ rm db.sqlite3

Then start the server. You should see the output below:

(venv) $ python manage.py runserver
Watching for file changes with StatReloader
Performing system checks...

System check identified no issues (0 silenced).

# ...

If, instead, you have this error:

Watching for file changes with StatReloader
Performing system checks...

System check identified no issues (0 silenced).
Exception in thread django-main-thread:
Traceback (most recent call last):

# ...
django.db.utils.OperationalError: FATAL:  Peer authentication failed for user "test"

Then you need to modify peer authentication to password authentication. Open the file pg_hba.conf (run locate pg_hba.conf to find where the file is):

(venv) $ sudo nano /etc/postgresql/12/main/pg_hba.conf

# change this line:

# "local" is for Unix domain socket connections only
local   all             all                                 peer

# to this:

# "local" is for Unix domain socket connections only
local   all             test                                md5

Don’t forget to restart the server:

(venv) $ sudo service postgresql restart

Using a Custom User Model

In the Django documentation, they highly recommend setting up a custom user model when starting a new project, even if the default one is sufficient for us. And since we need to extend the user model later, we are going to follow this recommendation.

First, we need to create an app:

(venv) $ python manage.py startapp users

Then open the file users/models.py and add these lines:

# users/models.py
from django.db import models
from django.contrib.auth.models import AbstractUser

class User(AbstractUser):
    pass

Now we need to add the app in the INSTALLED_APPS settings and point AUTH_USER_MODEL to our custom user model:

# blog/settings.py
INSTALLED_APPS = [
  # ...
  'users',
]

# ...

AUTH_USER_MODEL = 'users.User'

and register the model in users/admin.py:

# users/admin.py
from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from .models import User

admin.site.register(User, UserAdmin)

Finally, we can run the migrations:

(venv) $ python manage.py makemigrations
Migrations for 'users':
users/migrations/0001_initial.py
  - Create model User

(venv) $ python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, sessions, users
Running migrations:
  Applying contenttypes.0001_initial... OK

  # ...

If you want to learn more about custom user models, check out this post Django: Custom User Model Extending AbstractUser.

Hello World

To finish this part we are going to create a simple page that displays «Hello World».

First, let’s create a new app:

(venv) $ python manage.py startapp core

and add it to INSTALLED_APPS:

# blog/settings.py
INSTALLED_APPS = [
  # ...
  'users',
  'core',
]

So far our project structure looks like this:

|── myproject/
|    |── blog/
|    |    |── asgi.py
|    |    |── __init__.py
|    |    |── settings.py
|    |    |── urls.py
|    |    |── wsgi.py
|    |── core/               
|    |    |── migrations/
|    |    |    |── __init__.py
|    |    |── admin.py
|    |    |── apps.py
|    |    |── __init__.py
|    |    |── models.py
|    |    |── tests.py
|    |    |── views.py
|    |── users/               
|    |    |── migrations/
|    |    |    |── __init__.py
|    |    |── admin.py
|    |    |── apps.py
|    |    |── __init__.py
|    |    |── models.py
|    |    |── tests.py
|    |    |── views.py
|    |──venv/
|    |── manage.py

Template Configuration

Good. Now we have to create a new folder named templates in the root directory where manage.py live:

|── myproject/
|    |── blog/
|    |── core/
|    |── templates/     <-- here!
|    |── users/
|    |── venv/
|    |── manage.py

and inside the templates folder, create a file named base.html:

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
  <!-- Bootstrap CSS -->
  <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css"
    integrity="sha384-JcKb8q3iqJ61gNV9KGb8thSsNjpSL0n8PARn9HuZOnIxN0hoP+VmmDGMN5t9UJ0Z" crossorigin="anonymous">

  <title>{% block head_title %}Welcome - Blog{% endblock %}</title>
</head>

<body>
  <h1>Hello World !</h1>

  <!-- jQuery first, then Popper.js, then Bootstrap JS -->
  <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"
    integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj"
    crossorigin="anonymous"></script>
  <script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js"
    integrity="sha384-9/reFTGAW83EW2RDu2S0VKaIzap3H66lZH81PoYlFhbGU+6BZp6G7niu735Sk7lN"
    crossorigin="anonymous"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"
    integrity="sha384-B4gt1jrGC7Jh4AgTPSdUtOBvfO8shuf57BaghqFfPlYxofvL8/KUEfYiJOMMV+rV"
    crossorigin="anonymous"></script>
</body>
</html>

It is recommended adding Bootstrap in a project via CDN (Content Delivery Network) for multiple reasons:

They are hosting the files on multiple servers, so the loading time is reduced.
The libraries are automatically updated.
SEO improved …

After that we need to tell Django where to find our application’s templates.

# blog/settings.py
  
TEMPLATES = [
  {
      'BACKEND': 'django.template.backends.django.DjangoTemplates',
      'DIRS': [BASE_DIR / 'templates'],  # <-- add this 
      'APP_DIRS': True,
      'OPTIONS': {
          # ...
          ],
      },
  },
]

The last step is to have a view that render the HTML file above. We are going to use a class based view.

Open the urls.py file and add the code below:

# blog/urls.py
# ...
from django.views.generic import TemplateView

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', TemplateView.as_view(template_name='base.html'), name='home')
]

Finally, let’s create a superuser and add a requirements.txt file:

(venv) $ python manage.py createsuperuser
Username: test
Email address: 
Password:             # 1234
Password (again):     # 1234
# ...
Superuser created successfully.
(venv) $ pip freeze > requirements.txt

Ok, so far so good! We have all the pieces in place to start the core of our project. The blog!

I hope you enjoyed going through this first part of the tutorial as much as I enjoyed writing the content. See you in the next part.

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Build a Blog with Django #1: Project Configuration