How to add environment variables to your Django app.

<pre class="language-markup"><code>pip install python-dotenv</code></pre>
<p>This package will take care of our environment variables.</p>
<h4>Quick explanation:</h4>
<p>Environment variables change based on the environment in which we're running our Django project (production, development...).&nbsp;</p>
<p><strong>Examples:</strong></p>
<p>DEBUG; this variable should be <strong>False</strong> in production, and <strong>True</strong> in our local environment.</p>
<p>This is why we're going to create a separate file called (.env) that will hold our DEBUG variable. The file won't be staged to version control. Then we're going to create the .env file manually in our production environment, it will also hold our debug variable but with a different value.</p>

Install python-dotenv

<p>On the top of your settnigs.py file:</p>
<pre class="language-markup"><code>import os
from dotenv import load_dotenv

load_dotenv()</code></pre>
<p>This will load the package and will give us the possibility to read our environment variables from a .env file.</p>

settings.py

<p>Your django project's secret key is something that you want to hold secret. So if you pushed your current secret key to GitHub, you need to generate a new secret key and make it an environment variable. The new secret key should not be visible in the GitHub repository.</p>
<h4>To generate a new secret key:</h4>
<pre class="language-markup"><code>python manage.py shell</code></pre>
<pre class="language-python"><code>from django.core.management.utils import get_random_secret_key
print(get_random_secret_key())</code></pre>
<p>You will get a secret key. Store it somewhere safe, we'll need it later.</p>
<p>Now, in your <strong>settings.py</strong> file:</p>
<pre class="language-ruby"><code>SECRET_KEY = os.getenv('SECRET_KEY', 'top-secret-change-me')</code></pre>
<p><strong>Note:</strong>&nbsp;Replace the default_secre_key with the secret key that previously existed in your django project.</p>
<h4>.env file:</h4>
<p>After creating a .env file, add this line to it:</p>
<pre class="language-markup"><code>SECRET_KEY=&lt;your_generated_secret_key&gt;</code></pre>
<p><strong>Note:</strong> Make sure to add the secret key you generated before using the get_random_secret_key()&nbsp;</p>

SECRET_KEY

<h4>settings.py:</h4>
<pre class="language-python"><code>DEBUG = os.getenv('DEBUG', 'True') == 'True'</code></pre>
<h4>Explanation:</h4>
<p>The comparison <code>os.getenv('DEBUG') == 'True'</code> compares the retrieved value with the string <code>'True'</code>. This comparison will be <code>True</code> if the value of the <code>DEBUG</code> environment variable is <code>'True'</code>, and <code>False</code> otherwise.</p>
<h4>.env file:</h4>
<p>Add this line to the .env file:</p>
<pre class="language-markup"><code>DEBUG=True</code></pre>
<p><strong>Note:</strong> Change True to False if your .env file is for production purposes.&nbsp;</p>

DEBUG

<h4>settings.py:</h4>
<pre class="language-python"><code>ALLOWED_HOSTS = os.getenv('ALLOWED_HOSTS', '127.0.0.1').split(',')</code></pre>
<h4>Explanation:</h4>
<p>If the environment variable is not set or is empty, the default value <code>''</code> will be used. The <code>split(',')</code> method splits the value by commas and returns a list of host names.</p>
<h4>.env file:</h4>
<p>Add this line to the .env file:</p>
<pre class="language-markup"><code>ALLOWED_HOSTS=example.com,www.anotherexample.com</code></pre>
<p><strong>Note:&nbsp;</strong>Change the domains to your desired domains. Note that ALLOWED_HOSTS is not taken into consideration if DEBUG is True.</p>

ALLOWED_HOSTS

<h4>settings.py</h4>
<pre class="language-python"><code>DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}

POSTGRES_DB = os.getenv("POSTGRES_DB") #database name
POSTGRES_PASSWORD = os.getenv("POSTGRES_PASSWORD") # database user password
POSTGRES_USER = os.getenv("POSTGRES_USER") # database username
POSTGRES_HOST = os.getenv("POSTGRES_HOST") # database host
POSTGRES_PORT = os.getenv("POSTGRES_PORT") # database port

POSTGRES_READY = (
    POSTGRES_DB is not None
    and POSTGRES_PASSWORD is not None
    and POSTGRES_USER is not None
    and POSTGRES_HOST is not None
    and POSTGRES_PORT is not None
)

if POSTGRES_READY:
    DATABASES = {
        "default": {
            "ENGINE": 'django.db.backends.postgresql_psycopg2',
            "NAME": POSTGRES_DB,
            "USER": POSTGRES_USER,
            "PASSWORD": POSTGRES_PASSWORD,
            "HOST": POSTGRES_HOST,
            "PORT": POSTGRES_PORT,
        }
    }</code></pre>
<p>We're trying to set up our Django project so that it forms a connection with a Postgres database when the environment variables are set in the environment file. So if you don't wish to use a Postgres database in your local machine, you can just not add the Postgres environment variables.</p>
<h4>.env file:</h4>
<p>Add these lines to the .env file:</p>
<pre class="language-markup"><code>POSTGRES_DB=&lt;your_postgres_db_name&gt;
POSTGRES_PASSWORD=&lt;your_postgres_db_password&gt;
POSTGRES_USER=&lt;your_postgres_db_user&gt;
POSTGRES_HOST=&lt;your_postgres_db_host&gt;
POSTGRES_PORT=&lt;your_postgres_db_port&gt;</code></pre>
<p><strong>Note:&nbsp;</strong>Make sure to change the values with your own.</p>

DATABASES

<p>This is how our .env file will look like:</p>
<pre class="language-markup"><code>SECRET_KEY=&lt;your_secret_key&gt;
DEBUG=True
ALLOWED_HOSTS=example.com,www.anotherexample.com
POSTGRES_DB=&lt;your_postgres_db_name&gt;
POSTGRES_PASSWORD=&lt;your_postgres_db_password&gt;
POSTGRES_USER=&lt;your_postgres_db_user&gt;
POSTGRES_HOST=&lt;your_postgres_db_host&gt;
POSTGRES_PORT=&lt;your_postgres_db_port&gt;</code></pre>

Add Environment Variables to your Django project

Install python-dotenv

Quick explanation:

Install python-dotenv

settings.py

SECRET_KEY

DEBUG

ALLOWED_HOSTS

DATABASES

.env file