haskell-servant/example-servant-elm

Example for a web app with a servant backend and an elm frontend

Haskell Servant and Elm Example

This example project illustrates how to set up a project that:

• Uses haskell and servant as a backend exposing a JSON api (and serving some files).
• Uses elm to write the frontend.
• Uses servant-elm to generate client functions in elm for the JSON api. This means that mismatches regarding the JSON api will be detected statically.
• Allows a very fast development cycle: You can type-check the server and client code in a very short amount of time.

Makefile

There's a Makefile included with the following targets:

• setup -- Set up everything: install ghc and dependencies. (Needs stack, elm and elm-test.)
• build -- Build the server and the client.
• server-start -- Start the server here: http://localhost:3000/. Requests sent to this server will trigger a recompilation of the client code (not the server code).
• test -- Recompiles the client and server code. And runs the test-suite.

Caveats

• This project uses https://travis-ci.org/soenkehahn/wai-make-assets, which is experimental. E.g. there's no support for serving the assets in a production setting.

More examples

This repository demonstrates a servant backend and an elm frontend. More code generation examples can be found in haskell-servant/servant-elm.