Tutorial for installing Heroku's command-line tool, and launch an example Django website.

• This is for brand new Python users, including coding class students who want a simple and to-the-point guide on getting Heroku working on their system to launch Python websites.

• This guide assumes you already have fundamental Bash knowledge.

• This guide does not support Windows. It assumes you use either macOS or Ubuntu GNU/Linux.

This was original created for Kickstart Coding, the affordable, inclusive, and intensive coding course teaching cutting-edge Python / Django and JavaScript / React web development in Oakland, CA. Learn more and enroll here.

Heroku is a company that will run an HTTP server application for you on their servers.

They will do the heavy lifting of installing PyPI dependencies and making sure the right HTTP requests get to your servers (routing), you in turn need to only make sure your application is properly configured. Also important: They have a "freemium" payment model, where there is a "free-tier" that is great for learning without spending any money.

Heroku is now a subsidiary of SalesForce, and in turn rents its server space according to an agreement with Amazon Web Services.

• Heroku (the business) - a company that will run your HTTP server application for you, and expose it to the web.

• heroku (the CLI command) - A tool that Heroku the company has developed which we will use for interacting with your Heroku account, and launching applications.

• heroku app - One particular application you are running on a Heroku server.

• heroku add-on - Extra stuff your application needs, such as databases or media file services. These might cost money, and might be provided by a third party.

Now that you know a little about Heroku, it's time to install their CLI tool on your system and get used to using it.

• First, go to the Heroku.com website and sign up for an account. Remember your username and password, you will be using it in a moment.

• You may want to add in your credit card information -- although optional, it unlocks more free apps and add-ons at once even if you never buy anything.

Either use the Ubuntu Software Center (search for Heroku and click Install), or run the following command:

sudo snap install heroku

Run the following command:

brew install heroku/brew/heroku

Login to Heroku (should only have to do this once):

heroku login

Broad concepts:

• For every web project you are working on, if you want to publish it, you should create for it a Heroku app.

• Heroku acts a little like GitHub: They provide a remote Git server that we can push to. So, when you create an app, you are also creating a remote repo to store your code (much like GitHub).

• Whenever Heroku receives code from us via a git push, they will then try to run that code on their servers, and expose it to the world.

Every time you want to launch a brand new Python project, you will need to create a new Heroku app for it. These are the steps to both create a new heroku app, and link your git repo to it.

NOTE: For this tutorial, this repo contains an example Django project you can launch! Feel free to git clone this repo, and use it as your example Django project to launch.

1. Go to the directory of your Django project.

2. Ensure your Django project has a Procfile (see the 5.3/activities/minidjango example) - this tells Heroku which file is the main "entry point" to your server, in other words, which file to run to kick everything off.

3. Ensure your Django project has a Pipfile - again, see the mindjango example. If you have been using pipenv, you should be good to go on this front.

4. IMPORTANT: Your project MUST be in a git repository. You can either do this the normal way by going to GitHub and creating a new repo, then cloning that, OR you can use the "git init" command to make a local-only repo. However you do it, Heroku absolutely requires your project to be in a single git repo, such that the Procfile, Pipfile, and manage.py are all at the "top level" next to README.md and .git, etc.

5. Create a new Heroku Application on your account for your project:

heroku create

6. Ensure that your git repo is now linked to a Heroku remote, in addition to GitHub:

# You should see both "origin" twice and "heroku" twice (4 lines) when running # the following git command: git remote -v

If all went well, you are good to go! Deploy your app to Heroku:

git push heroku master

If it's working, you should see text like "Python app detected", then after a 30 seconds or so, something like:

remote: -----> Launching... remote: Released v4 remote: https://secure-lake-12038.herokuapp.com/ deployed to 

That strange URL "secure-lake-12038" will be a different combo of random words and numbers for you, but will be the URL of your new app! Click on that link or copy and paste it into your browser to see your application live for the world to see.

As you work on your project, after every change that you want to test on Heroku, make a commit (git add -A, git commit -m) and then repeat the previous last step (git push heroku master).

• By default, they pick a weird, random domain name, but you can customize it later if you want to have a custom name, or even a purchased domain name.

• If you want to launch code to Heroku, it must be in a brand new commit. So, whenever you want to relaunch to the world, you will need to create a new commit.