Index

• Tech stack
• Getting started
• File structure
• More instructions
• Deploying to Heroku

Tech stack

• FastAPI: Web framework. Like Flask, but faster, with automatic interactive docs.
• Flake8: Linter, enforces PEP8 style guide.
• Heroku: Platform as a service, hosts your API.
• Pipenv: Reproducible virtual environment, manages dependencies.
• Pytest: Testing framework, runs your unit tests.

Getting started

Create a new repository from this template.

Clone the repo

git clone https://github.com/YOUR-GITHUB-USERNAME/YOUR-REPO-NAME.git

cd YOUR-REPO-NAME

Install dependencies

pipenv install --dev

Activate the virtual environment

pipenv shell

Launch the app

uvicorn app.main:app --reload

Go to localhost:8000 in your browser.

You'll see your API documentation:

• Your app's title, "DS API"
• Your description, "Lorem ipsum"
• An endpoint for POST requests, /predict
• An endpoint for GET requests, /vis/{statecode}

Click the /predict endpoint's green button.

You'll see the endpoint's documentation, including:

• Your function's docstring, """Make random baseline predictions for classification problem."""
• Request body example, as JSON (like a Python dictionary)
• A button, "Try it out"

Click the "Try it out" button.

The request body becomes editable.

Click the "Execute" button. Then scroll down.

You'll see the server response, including:

• Code 200, which means the request was successful.
• The response body, as JSON, with random baseline predictions for a classification problem.

File structure

.
└── app
    ├── __init__.py
    ├── main.py
    ├── api
    │   ├── __init__.py
    │   ├── predict.py
    │      
    └── tests
        ├── __init__.py
        ├── test_main.py
        ├── test_predict.py
        

More instructions

Activate the virtual environment

pipenv shell

Install additional packages

pipenv install PYPI-PACKAGE-NAME

Launch a Jupyter notebook

jupyter notebook

Run tests

pytest

Run linter

flake8

calmcode.io videos - flake8

Deploying to Heroku

Prepare Heroku

heroku login

heroku create YOUR-APP-NAME-GOES-HERE

heroku git:remote -a YOUR-APP-NAME-GOES-HERE

Deploy to Heroku

git add --all

git add --force Pipfile.lock

git commit -m "Deploy to Heroku"

git push heroku main:master

heroku open

(If you get a Locking failed! error when deploying to Heroku or running pipenv install then delete Pipfile.lock and try again, without git add --force Pipfile.lock)

Deactivate the virtual environment

exit