How to Install Pyenv on Ubuntu 24.04

Emdadul Huq — Thu, 25 Jul 2024 06:07:36 +0000

Due to the slowness of repositories or even lack thereof being updated with specific versions of Python, I’ve decided to move some of my environments over to Pyenv to allow me to dynamically install and configure Python specifically for my environment. As it turns out this will also allow VS Code to allow me to choose the version of Python that I’d like to use when testing. So, here’s a quick guide to installing Pyenv on Ubuntu 24.04

Update and install dependencies

we need to ensure our package cache is updated, and then install the dependencies to download, and build python from pyenv.



sudo apt-get update && sudo apt-get install make build-essential

Install Pyenv using pyenv-installer



curl https://pyenv.run | bash

Configure user profile to use pyenv

Ensure the following is in your ~/.bash_profile (if exists), ~/.profile (for login shells), ~/.bashrc (for interactive shells), or ~/.zshrc



# Load pyenv automatically by appending
# the following to 
# ~/.bash_profile if it exists, otherwise ~/.profile (for login shells)
# and ~/.bashrc (for interactive shells) :

export PYENV_ROOT="$HOME/.pyenv"
[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"
eval "$(pyenv init -)"

Optionally enable pyenv-virtualenv



eval "$(pyenv virtualenv-init -)"

Reload your profile



source ~/.profile

Install python using pyenv



pyenv install <version>

Set your python version

pyenv shell — select just for current shell session
pyenv local — automatically select whenever you are in the current directory (or its subdirectories)
pyenv global — select globally for your user account

Validate your installation of python



python3 --version

Reference Pyenv

How to configure an Nginx server on Ubuntu 22.04 with Django and uWSGI

Emdadul Huq — Sat, 09 Sep 2023 09:43:41 +0000

1. Update Your Server

It’s always a good idea to start by updating your server.

sudo apt-get update
sudo apt-get upgrade

Now we have the latest and greatest packages installed on the server.

2. Use a Virtual Environment for Python

The venv module allows you to create virtual Python environments. This allows you to isolate installed packages from the system.

After installing venv, make a directory to house your virtual environments, and then create a virtual environment named env using venv. You can call your virtual environment whatever you prefer.

sudo apt-get install python3-venv
mkdir Workstations && cd Workstations
python3 -m venv env

Now activate your virtual environment.

source env/bin/activate

You will see the name of your virtual environment in the parenthesis as a prefix to your env

3. Create a Django Project

Now we install the Django web framework using the pip package installer.

pip install Django

Next let’s create a Django project with django-admin which should be on your path by default. Feel free to choose a project name that suites you. For example we will use the name of our project called mysite.

django-admin startproject mysite
cd mysite

Now test our project using following commands:

python manage.py runserver 0.0.0.0:8000

In a browser, you should be able to visit mysite:8000 and see the default Django landing page, if not, you might you be see a error message like this:

if you see this error message, add your domain name to the mysite/settings.py file.

Try to visit mysite.com:8000 again and this time you will see the Django landing page.

4. Get Started with uWSGI

First we need to install the web server gateway interface (WSGI). In this case, we will be using uWSGI. You will also need the development packages for your version of Python to be installed.

sudo apt-get install python3.8-dev
sudo apt-get install gcc
pip install uwsgi

We will see to send requests from the client to Nginx which will pass them to a socket that will hand them off to uWSGI before finally being given to Django.

Create a file called server-test.py with the following content:

def application(env, start_response):
    start_response('200 OK', [('Content-Type','text/html')])
    return [b"Hello World!"]

Let's test our uWSGI directly talking to python with the following command

uwsgi --http :8000 --wsgi-file server-test.py

In a browser, you should be able to visit mysite.com:8000 and see the test Hello World!

If this works for you, we have demonstrated that uWSGI is able to pass requests to Python.

Now we can similarly serve the Django Project with the following command:

uwsgi --http :8000 --module mysite.wsgi

Note that this works because the path mysite/wsgi.py exists.

5. Configure the Nginx Web Server

Install Nginx with apt-get as follows:

sudo apt-get install nginx

Now with Nginx installed, you will be able to visit the default Welcome to nginx! page in your browser at http://mysite.com .

Let’s tell Nginx about our Django project by creating a configuration file at /etc/nginx/sites-available/mysite.conf. Change the highlighted lines to suite your needs.

# the upstream component nginx needs to connect to
upstream django {
    server unix:///home/emdad/mysite/mysite.sock;
}
# configuration of the server
server {
    listen      80;
    server_name mysite.com www.mysite.com;
    charset     utf-8;
    # max upload size
    client_max_body_size 75M;
    # Django media and static files
    location /media  {
        alias /home/emdad/mysite/media;
    }
    location /static {
        alias /home/emdad/mysite/static;
    }
    # Send all non-media requests to the Django server.
    location / {
        uwsgi_pass  django;
        include     /home/emdad/mysite/uwsgi_params;
    }
}

We need to create the /home/emdad/mysite/uwsgi_params file highlighted above on line 26 as well.

uwsgi_param  QUERY_STRING       $query_string;
uwsgi_param  REQUEST_METHOD     $request_method;
uwsgi_param  CONTENT_TYPE       $content_type;
uwsgi_param  CONTENT_LENGTH     $content_length;
uwsgi_param  REQUEST_URI        $request_uri;
uwsgi_param  PATH_INFO          $document_uri;
uwsgi_param  DOCUMENT_ROOT      $document_root;
uwsgi_param  SERVER_PROTOCOL    $server_protocol;
uwsgi_param  REQUEST_SCHEME     $scheme;
uwsgi_param  HTTPS              $https if_not_empty;
uwsgi_param  REMOTE_ADDR        $remote_addr;
uwsgi_param  REMOTE_PORT        $remote_port;
uwsgi_param  SERVER_PORT        $server_port;
uwsgi_param  SERVER_NAME        $server_name;

Next we can publish our changes by creating a symbolic link from sites-available to sites-enabled like so:

sudo ln -s /etc/nginx/sites-available/mysite.conf /etc/nginx/sites-enabled/

We must edit the mysite/settings.py file to explicitly tell Nginx where our static files reside.

First add import os at the very beginning:

"""
Django settings for mysite project.
Generated by 'django-admin startproject' using Django 3.1.2.
For more information on this file, see
https://docs.djangoproject.com/en/3.1/topics/settings/
For the full list of settings and their values, see
https://docs.djangoproject.com/en/3.1/ref/settings/
"""
import os
from pathlib import Path
# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent

and STATIC_ROOT = os.path.join(BASE_DIR, "static/") at the very end:

...
# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.1/howto/static-files/
STATIC_URL = '/static/'
STATIC_ROOT = os.path.join(BASE_DIR, "static/")

With these changes in place, we can now tell Django to put all static files in the static folder.

python manage.py collectstatic

Restart the Nginx server to apply changes.

sudo /etc/init.d/nginx restart

At this point if you visit http://mysite.com a browser, you will probably see an Nginx 502 Bad Gateway error,

mkdir media
wget https://www.google.com/logos/doodles/2020/thank-yo…c-transportation-workers-6753651837108759-2xa.gif -O media/media.gif

Finally visit http://mysite.com/media/media.gif in a browser and you should see the image

6. Get Nginx, uWSGI, and Django to Work Together

Let’s take this one step further and have Nginx, uWSGI, and Django work together with the help of the UNIX socket.

uwsgi --socket mysite.sock --module mysite.wsgi --chmod-socket=666

You can actually try the above command without the --chmod-socket=666 argument and/or with a --chmod-socket=664 argument instead. If either of those work for you, just keep that in mind going forward.

Once again, visit http://mysite.com in a browser, and this time you should see the default Django landing page!

7. Configure uWSGI for Production

we configure a file at the root of your Django project called mysite_uwsgi.ini .

[uwsgi]
# full path to Django project's root directory
chdir            = /home/emdad/mysite/
# Django's wsgi file
module           = mysite.wsgi
# full path to python virtual env
home             = /home/emdad/env
# enable uwsgi master process
master          = true
# maximum number of worker processes
processes       = 10
# the socket (use the full path to be safe
socket          = /home/emdad/mysite/mysite.sock
# socket permissions
chmod-socket    = 666
# clear environment on exit
vacuum          = true
# daemonize uwsgi and write messages into given log
daemonize       = /home/emdad/uwsgi-emperor.log

You can then proceed to start up uwsgi and specify the ini file:

uwsgi --ini mysite_uwsgi.ini

visit http://mysite.com in a browser and see the default Django landing page if everything works correctly.

As one last configuration option for uWSGI, let’s run uWSGI in emperor mode. This will monitor the uWSGI config file directory for changes and will spawn vassals (i.e. instances) for each one it finds.

cd /home/emdad/mysite/env/
mkdir vassals
sudo ln -s /home/emdad/mysite/mysite_uwsgi.ini /home/emdad/env/vassals/

Now you can run uWSGI in emperor mode as a test.

uwsgi --emperor /home/emdad/env/vassals --uid www-data --gid www-data

Visit http://mysite.com a browser and you will see the default Django landing page if everything works correctly.

Finally, we want to start up uWSGI when the system boots. Create a systemd service file at /etc/systemd/system/emperor.uwsgi.service with the following content:

[Unit]
Description=uwsgi emperor for mysite domains website
After=network.target
[Service]
User=emdad
Restart=always
ExecStart=/home/emdad/mysite/env/bin/uwsgi --emperor /home/emdad/mysite/env/vassals --uid www-data --gid www-data
[Install]
WantedBy=multi-user.target

Enable the service to allow it to execute on system boot and start it so you can test it without a reboot.

systemctl enable emperor.uwsgi.service
systemctl start emperor.uwsgi.service