Concentrate

Concentrate combines realtime transit information from multiple sources into single output files.

Configuration

Concentrate can either be configured via config/config.exs or a JSON environment variable as CONCENTRATE_JSON: more details are available in configuration.md.

An example run commands bash script for configuring Concentrate is available in .envrc.example. Note that you must run apply this configuration in a bash shell by using source instead of via direnv or a similar tool, since it runs bash commands.

Architecture

See architecture.md for the overall architecture of the system.

Development Setup

# after installing asdf from https://github.com/asdf-vm/asdf..
asdf install

# get Elixir dependencies
mix deps.get

# add pre-commit hook to verify formatting/tests/types
ln -s hooks/pre-commit .git/hooks/pre-commit

# make sure everything passes! (fastest to slowest)
mix format --check-formatted
mix credo
mix dialyzer

See the section on tests below for information on running unit tests, which requires having a local MQTT broker running.

If you run into issues compiling snabbkaffe:

rm -fr deps/quicer
mix deps.get
mix deps.compile

Tests

To run the tests, first install and set up Colima, Docker, and docker-compose:

brew install docker docker-compose colima
colima start
mkdir -p ${DOCKER_CONFIG:-"$HOME/.docker"}/cli-plugins
ln -sfn /opt/homebrew/opt/docker-compose/bin/docker-compose ${DOCKER_CONFIG:-"$HOME/.docker"}/cli-plugins/docker-compose

Then start the Compose configuration and run the tests:

1. In a separate window or tab: docker compose up
2. mix test

Docker

Concentrate comes with a Dockerfile, allowing you to build an image that can be run anywhere Docker works. It's a multi-stage build, so it requires at least Docker 17.05.

# build
docker build -t concentrate:latest .

# run
docker run concentrate:latest