Production Haskell Demystified

Table of Contents

• Prerequisites
• Run the Demo API
• Development Tooling

Prerequisites

Install the Haskell Tool Stack

From the project root, run:

stack test --fast

...which will download and set up GHC, retrieve package dependencies, build the project, and run the test suite (with -O0 optimizations to speed things up).

Run the Demo API

From the project root, run

make build-fast && stack exec demo

...which will recompile the project and start the web server on port 8080.

Check out the following routes to see the server in action:

• Swagger documentation: http://localhost:8080/docs/index.html
• Users: http://localhost:8080/v1/users
• Admins: http://localhost:8080/v1/users/admins
• Moderators: http://localhost:8080/v1/users/moderators
• Basic Users: http://localhost:8080/v1/users/basic

Development Tooling

I've included a Makefile with this project that captures a lot of my common development flows within a Haskell project.

Since some of these commands are dependent on ghcid, so before running any of them make sure its installed and available on your path with stack install ghcid.

To build the project quickly:

make build-fast

To enter the project REPL:

make ghci

To run ghcid, which will recompile the project on changes and output any type errors to the console:

make ghcid

To run ghcid and have it rerun the test suite after the project successfully type checks:

make ghcid-test

To run the test suite on its own:

make test