Coffee DB

Coffee DB is a web app to track purchases of bags of coffee. The app is built with a Streamlit frontend, which allows you to add new coffees and visualise the coffee database. The backend uses a postgres SQL database to store the coffees. Both the app and the databse are hosted using Heroku. The app can be accessed at the following url: https://coffee-db.herokuapp.com/

Running Locally

In order to run the app locally, it requires you to have postgresql installed on your machine. Once postgresql is installed, run the helpers/db_init.sql file to build the database that matches the production schemas. This will give you the correct tables for the app to run correctly.

In order to connect locally, add a settings.ini file in the root directory of the project. The file should look like the following:

[postgresql]
host=localhost
dbname=your_database
user=your_user
password=your_password

Install the requirements either through Poetry or through the requirements.txt.

pip install -r requirements.txt

or

poetry install

Then run the streamlit app from the root directory.

streamlit run app.py

Package management with Poetry and requirements.txt

The project uses poetry for it's package management. However, the Python buildpack for Heroku requires a requirements.txt (see docs) file to be available. To generate the requirements.txt from the poetry environment, run the following command:

poetry export --without-hashes --format=requirements.txt > requirements.txt

Formatting with Make

There is a simple github action to test formatting and linting using black and flake8 respectively. To run these checks locally prior to pushing your changes, use the following command:

make lint

Testing with pytest

The project uses pytest for testing. Testing is split into unit-tests and integration tests. The tests are checked as part of the CICD pipeline, but they can be run manually with the following make commands:

make unit-tests
make integration-tests

Note: In order for the tests to pass, you must have an available connection to a PSQL database. Note: Integration tests use TestContainers to run a fresh psql database in an isolated container.

Heroku Commands

Deploying to Heroku

The repository is set to automatically deploy when pushing to main, dependant on the CI pipelines passing. You can manually deploy the app using the following command:

git push heroku main

Heroku PSQL CLI

Use the following command to interact with the deployed psql database:

heroku pg:psql