reserve

DISCLAIMER: This is early stage software. It is already functional and useful, but it still has some rough edges.

reserve provides code reloading for Haskell web applications. You can run you application with reserve during development and code changes will take immediate effect.

Requirements

reserve can reload arbitrary Haskell web applications. The only requirement is that your application works with ghci.

Examples

Scotty

Create a file app.hs with the following content:

{-# LANGUAGE OverloadedStrings #-}
import Web.Scotty

main :: IO ()
main = scotty 3000 $ do
  get "/" $ do
    text "hello\n"

$ reserve app.hs

Make a request to http://localhost:12000, modify app.hs, reload!

Snap (sandboxed)

$ mkdir my-project && cd my-project
$ cabal sandbox init
$ cabal install snap
$ cabal exec snap init barebones
$ cabal exec -- reserve -p 8000

Make a request to http://localhost:12000, modify src/Main.hs, reload!

Customization

By default reserve assumes that the Main module of your application is at src/Main.hs. You can customize this by passing the path to your Main module to reserve:

$ reserve src/app.hs

By default reserve assumes that your application listens on port 3000. You can customize this by passing --port to reserve:

$ reserve --port 8000

By default reserve serves your application on port 12000. You can customize this by passing --reserve-port to reserve:

$ reserve --reserve-port 4040

You can pass command-line arguments to your application by separating them with --:

$ reserve src/app.hs -- --mode development

reserve uses ghci to run your application. If your application requires any addition GHC options, you can put them into ./.ghci:

$ echo ":set -isrc" >> .ghci
$ reserve src/app.hs

reserve works with Cabal sandboxes, just run it with cabal exec -- reserve.