Heroku and Python Deployment Demo

You’ll learn how to register a domain name, configure your DNS, and deploy a basic website using Heroku!

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Things you should have already:

• GitHub account.
• Heroku account.
• Account with domain registrar of choice. This one is simple.
• Fingers to type with.

Things we're gonna do.

1. Write a simple app in Python using Flask
2. Run our app locally.
3. Deploy said app to the cloud via Heroku.
4. Register a domain.
5. Setup DNS to point to our app.

Simple Flask App

• Clone this repo: git clone git@github.com:michiganhackers/heroku-py-demo.git
• Install Virtualenv: pip install virtualenv (may need sudo).
  (If you're wondering, this is for creating an isolated python environment.)
• Run virtualenv venv --distribute to start up a virtual environment.
• Run: source venv/bin/activate to start up the virtualenv.
• Install Flask: pip install -r requirements.txt.

Now we are ready to run it!

• Type python server.py to run the app.
• Navigate to http://localhost:3000/
• Notice if you make changes to the file the server will restart automatically.

Notes:

• The Procfile is used by Heroku to start your app.
• Heroku uses Foreman to run your app, you can too! Try foreman start.
• If you add new pip modules use pip freeze > requirements.txt before deploying. (This way Heroku knows what your dependencies are.)
• More Heroku deployment details.

Deploy

• heroku login
• heroku create [yourappname] Make up a great app name.
• git push heroku master (If you dont have an ssh key on Heroku see below.)

Heroku will install dependences and launch your app here. Magic!

• heroku ps:scale web=1 This gives your app one web worker.
• heroku open This will go to yourappname.herokuapp.com
• Grab a beer.

SSH Key Upload:

• open new terminal window and type cat .ssh/id_rsa.pub
• if no file exists type ssh-keygen then hit enter (dont name a file)
• type a password if you want extra security. (Jack is wincing right now).
• type cat .ssh/id_rsa.pub again and copy only the printed lines.
• go to your account page and paste in the ssh key.

Next Time You Develop

source venv/bin/activate
python server.py to run locally.
git commit -am "commit message"
git push heroku master Update Heroku, no need to scale.
heroku open

Change to Your Own GitHub Repo

I'd love it if this repo were a starting point for your next big project. Create a repo on GitHub, and reset the origin url with the new one it gives you. git remote set-url origin git@github.com:you/your-repo.git
git push origin master

Domain Setup

• Find a domain.
• Pay for the domain.
• heroku domains:add www.example.com
• Add a DNS record with your provider's website:
  CNAME | www.example.com | yourappp.herokuapp.com
• More Heroku Domain Help