crystal-base-template

A base template for building applications, services, command line utilities, or libraries in crystal.

About ⭐

This template is designed to be a starting point for quickly getting your project off the ground in crystal-lang. It includes a number of features to help you get started quickly:

• ⚙️ Helper scripts for bootstrapping, testing, linting, formatting, and building your project
• 🏃 GitHub Actions CI/CD workflows for testing, building, linting, and running acceptance tests
• 🧪 A basic test structure
• 🐳 General purpose docker files for packing your crystal project into a container
• 📦 An opinionated dependency vendoring strategy because "you" own your availability

Dependency Vendoring 📦

This project uses a highly opinionated dependency vendoring strategy. This strategy is designed to ensure that you own your availability and can always build your project. This strategy is as follows:

1. All dependencies are vendored into the project into the lib/ directory
2. The lib/ directory is committed to the repository to ensure that all dependencies are available to build the project forever
3. The script/bootstrap command installs dependencies with SHARDS_CACHE_PATH="$DIR/.cache/shards" shards install ... to ensure that each project has its own cache and does not interfere with other crystal projects

Docker Strategy 🐳

This project also includes general purpose docker files for packing your crystal project into a container. The docker files are as follows:

• Dockerfile - A general purpose docker file for building and running your crystal project
• docker-compose.yml - A docker compose file for running your crystal project in a container (base configuration)
• docker-compose.override.yml - A docker compose file for running your crystal project in a container (override configuration, extends the base by default - good for development)
• docker-compose.production.yml - A docker compose file for running your crystal project in a container (production configuration, extends the base by default - must be used explicitly)

This project more or less assumes that all crystal projects will be run in a container. This is because crystal is a compiled language and the compiled artifacts are not always portable across different systems. Running your crystal project in a container ensures that the compiled artifacts are portable and can be run anywhere. The main Dockerfile also uses a multi-stage build to ensure that the final image is as small as possible and generally only contains the compiled artifacts.

Hint: the Makefile can be used to quickly start the development docker compose stack with make run (use make stop to stop the stack)

Usage 💻

Setup

Run the following command to bootstrap this repository and install all dependencies:

script/bootstrap

Testing

Run the following command to run all unit tests:

script/test

Run the following command to run all acceptance tests:

script/acceptance

Linting and Formatting

Run the following command to lint the project:

script/lint

script/lint --fix # to fix any linting errors

Run the following command to format the project:

script/format

script/format --check # to check if any files need to be formatted without formatting them

Building

Run the following command to create a release build:

script/build

All-in-one

Run the following command to run all of the above commands at once except for script/build:

script/all

This will lint and format the project, followed by running all unit tests.

Contributing 🤝

To get started quickly with this project, you will need the following installed:

• crystal (crenv is suggested)
• docker compose
• bash

To get your repo setup for development do the following:

1. Clone the repo
2. Ensure your version of crystal matches the version in .crystal-version
3. Run the following command:

script/bootstrap

1. Congrats you're ready to start developing!
2. Write some code
3. Run script/test to run unit tests and ensure your changes work
4. Run script/lint to ensure your changes follow the style guide
5. Run script/format to ensure your changes are formatted correctly
6. Run script/acceptance to run the acceptance test suite
7. Open a pull request 🎉