Chapter 1: Initial Set Up
This chapter covers how to properly configure your computer to work on Django projects. We start with an overview of the command line and how to install the latest versions of both Django (2.2) and Python (3.7). Then we discuss virtual environments, git, and working with a text editor. By the end of this chapter you’ll be ready to create and modify new Django projects in just a few keystrokes.
The Command Line
The command line is a powerful, text-only view of your computer. As developers we will use it extensively throughout this book to install and configure each Django project.
On a Mac, the command line is found in a program called Terminal located at
/Applications/Utilities. To find it, open a new Finder window, open the Applications directory, scroll down to open the Utilities directory, and double-click the application called Terminal.
On Windows machines there are actually two built-in command shells: the Command shell and PowerShell. You should use PowerShell, which is the more powerful of the two.
Going forward when the book refers to the “command line” it means to open a new console on your computer, using either Terminal or PowerShell.
While there are many possible commands we can use, in practice there are six used most frequently in Django development:
cd(change down a directory)
cd ..(change up a directory)
ls(list files in your current directory)
pwd(print working directory)
touch(create a new file)
Open your command line and try them out. The dollar sign (
$) is our command line prompt: all commands in this book are intended to be typed after the
For example, assuming you’re on a Mac, let’s change into our Desktop directory.
$ cd ~/Desktop
Note that our current location,
~/Desktop, is automatically added before our command line prompt. To confirm we’re in the proper location we can use
pwd which will print out the path of our current directory.
~/Desktop $ pwd /Users/wsv/desktop
On my Mac computer this shows that I’m using the user
wsv and on the
desktop for that account.
Now let’s create a new directory with
cd into it, and add a new file
index.html with the
touch command. Note that Windows machines unfortunately do not support a native
touch command. In future chapters when instructed to create a new file, do so within your text editor of choice.
~/Desktop $ mkdir new_folder ~/Desktop $ cd new_folder ~/Desktop/new_folder $ touch index.html
ls to list all current files in our directory. You’ll see there’s just the newly created
~/Desktop/new_folder $ ls index.html
As a final step, return to the Desktop directory with
cd .. and use
pwd to confirm the location.
~/Desktop/new_folder $ cd .. ~/Desktop $ pwd /Users/wsv/desktop
Advanced developers can use their keyboard and command line to navigate through their computer with ease. With practice this approach is much faster than using a mouse.
In this book I’ll give you the exact instructions to run–you don’t need to be an expert on the command line–but over time it’s a good skill for any professional software developer to develop. A good free resource for further study is the Command Line Crash Course.
Instructions are included below for installing Python 3 on Mac, Windows, and Linux computers.
Install Python 3 on Mac OS X (click here for Windows or Linux)
Although Python 2 is installed by default on Mac computers, Python 3 is not. You can confirm this by typing
python --version in the command line console and hitting Enter:
$ python --version Python 2.7.16
To check if Python 3 is already installed try running the same command using
python3 instead of
$ python3 --version Python 3.7.4
If your computer outputs
3.7.x (any version of 3.7 or higher) then skip ahead to creating a virtual environment.
However most likely you’ll see an error message since we need to install Python 3 directly.
Our first step is to install Apple’s Xcode package, so run the following command to install it:
$ xcode-select --install
Click through all the confirmation commands. Xcode is a large program so this might take a while to install depending on your internet connection.
Next, install the package manager HomeBrew via the longish command below:
$ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
To confirm HomeBrew installed correctly, run this command:
$ brew doctor Your system is ready to brew.
And now to install the latest version of Python, run the following command:
$ brew install python3
Let’s confirm which version was installed:
$ python3 --version Python 3.7.4
To open a Python 3 interactive shell–this lets us run Python commands directly on our computer–simply type
python3 from the command line:
$ python3 Python 3.7.4 (default, Sep 7 2019, 18:27:02) [Clang 10.0.1 (clang-1001.0.46.3)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
To exit the Python 3 interactive shell at any time type
Control+d (the “Control” and “d” key at the same time).
You can still run Python shells with Python 2 by simply typing
$ python Python 2.7.16 (default, Sep 7 2019, 18:27:02) [GCC 4.2.1 Compatible Apple LLVM 10.0.1 (clang-1001.0.46.4)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
Install Python 3 on Windows
Python is not included by default on Windows, however we can check if any version exists on the system. Open a command line console by entering
command on the Start Menu. Or you can hold down the SHIFT key and right-click on your desktop, then select Open Command Window Here.
Type the following command and hit RETURN:
python --version Python 3.7.3
If you see output like this, Python is already installed. Most likely it will not be!
To download Python 3, go to the downloads section of the official Python website. Download the installer and make sure to click the Add Python to PATH option, which will let use use
python directly from the command line. Otherwise we’d have to enter our system’s full path and modify our environment variables manually.
After Python has installed, run the following command in a new command line console:
python --version Python 3.7.4
If it works, you’re done!
Install Python 3 on Linux
Adding Python 3 to a Linux distribution takes a bit more work. Here are recommended recent guides for Centos and for Debian. If you need additional help adding Python to your PATH please refer to this Stack Overflow answer.
Virtual environments are an indispensable part of Python programming. They are an isolated container containing all the software dependencies for a given project. This is important because by default software like Python and Django is installed in the same directory. This causes a problem when you want to work on multiple projects on the same computer. What if ProjectA uses Django 2.1 but ProjectB from last year is still on Django 1.10? Without virtual environments this becomes very difficult; with virtual environments it’s no problem at all.
There are many areas of software development that are hotly debated, but using virtual environments for Python development is not one. You should use a dedicated virtual environment for each new Python project.
In this book we will use Pipenv to manage virtual environments. Pipenv is similar to
Pipfile containing software dependencies and a
Pipfile.lock for ensuring deterministic builds. “Determinism” means that each and every time you download the software in a new virtual environment, you will have exactly the same configuration.
Pipenv for each new Django Project.
Pipenv we can use
pip3 which HomeBrew automatically installed for us alongside Python 3.
$ pip3 install pipenv
Pipenv in action, let’s create a new directory and install Django. First navigate to the Desktop, create a new directory
django, and enter it with
$ cd ~/Desktop $ mkdir django $ cd django
Now use Pipenv to install Django.
$ pipenv install django==2.2.5
If you look within our directory there are now two new files:
Pipfile.lock. We have the information we need for a new virtual environment but we have not activated it yet. Let’s do that with
$ pipenv shell
If you are on a Mac you should now see parentheses around the name of your current directory on your command line which indicates the virtual environment is activated. Since we’re in a
django directory that means we should see
(django) at the beginning of the command line prompt.
Note that due to an open bug Windows users will not see visual feedback of the virtual environment at this time.
This means it’s working! Create a new Django project called
test_project with the following command. Don’t forget that period
. at the end.
(django) $ django-admin startproject test_project .
It’s worth pausing here to explain why you should add a period (
.) to the command. If you just run
django-admin startproject test_project then by default Django will create this directory structure:
└── test_project ├── manage.py └── test_project ├── __init__.py ├── settings.py ├── urls.py └── wsgi.py
See how it creates a new directory
test_project and then within it a
manage.py file and a
test_project directory? That feels redundant to me since we already created and navigated into a
django folder on our Desktop. By running
django-admin startproject test_project . with the period at the end–which says, install in the current directory–the result is instead this:
├── manage.py └── test_project ├── __init__.py ├── settings.py ├── urls.py └── wsgi.py
The takeaway is that it doesn’t really matter if you include the period or not at the end of the command, but I prefer to include the period and so that’s how we’ll do it in this book.
As you progress in your journey learning Django, you’ll start to bump up more and more into similar situations where there are different opinions within the Django community on the correct best practice. Django is eminently customizable, which is a great strength, however the tradeoff is that this flexibility comes at the cost of seeming complexity. Generally speaking it’s a good idea to research any such issues that arise, make a decision, and then stick with it!
Now let’s confirm everything is working by running Django’s local web server.
(django) $ python manage.py runserver
If you visit http://127.0.0.1:8000/ you should see the following image:
This is Django’s friendly welcome page. It lets us know that we’ve installed a new project successfully. We’ll be seeing it frequently in the coming chapter!
To stop our local server type
Control-c. Then exit our virtual environment using the command
(django) $ exit
We can always reactivate the virtual environment again using
pipenv shell at any time.
We’ll get lots of practice with virtual environments in this book so don’t worry if it’s a little confusing right now. The basic pattern is to install new packages with
pipenv, activate them with
pipenv shell, and then
exit when done.
It’s worth noting that only one virtual environment can be active in a command line tab at a time. In future chapters we will be creating a brand new virtual environment for each new project so either make sure to
exit your current environment or open up a new tab for new projects.
Git is an indispensable part of modern software development. It is a version control system which can be thought of as an extremely powerful version of track changes in Microsoft Word or Google Docs. With git, you can collaborate with other developers, track all your work via commits, and revert to any previous version of your code even if you accidentally delete something important!
On a Mac, because HomeBrew is already installed we can simply type
brew install git on the command line:
$ brew install git
On Windows you should download Git from Git for Windows. Click the “Download” button and follow the prompts for installation.
Once installed, we need to do a one-time system set up to configure it by declaring the name and email address you want associated with all your Git commits. Within the command line console type the following two lines. Make sure to update them your name and email address.
$ git config --global user.name "Your Name" $ git config --global user.email "firstname.lastname@example.org"
You can always change these configs later if you desire by retyping the same commands with a new name or email address.
The final step is our text editor. While the command line is where we execute commands for our programs, a text editor is where the actual code is written. The computer doesn’t care what text editor you use–the end result is just code–but a good text editor can provide helpful hints and catch typos for you.
Experienced developers often prefer using either Vim or Emacs, both decades-old, text-only editors with loyal followings. However each has a steep learning curve and requires memorizing many different keystroke combinations. I don’t recommend them for newcomers.
Modern text editors combine the same powerful features with an appealing visual interface. My current favorite is Visual Studio Code which is free, easy to install, and enjoys widespread popularity. If you’re not already using a text editor, download and install Visual Studio Code now.
Phew! Nobody really likes configuring a local development environment but fortunately it’s a one-time pain. We have now learned how to work with virtual environments and installed the latest version of Python and git. Everything is ready for our first Django app.
Continue on to Chapter 2: Hello World app.