elm-phoenix-socket

This library is a pure Elm interpretation of the Phoenix.Socket library that comes bundled with the Phoenix web framework. It aims to abstract away the more tedious bits of communicating with Phoenix, such as joining channels, leaving channels, registering event handlers, and handling errors.

Setup

Phoenix connections are stateful. The Socket module will manage all of this for you, but you need to add some boilerplate to your project to wire everything up.

1. Import all three Phoenix modules

   import Phoenix.Socket
   import Phoenix.Channel
   import Phoenix.Push

2. Add a socket to your model

   type alias Model =
     { phxSocket : Phoenix.Socket.Socket Msg
     }

3. Initialize the socket. The default path for Phoenix in development is "ws://localhost:4000/socket/websocket".

   init =
     { phxSocket = Phoenix.Socket.init "PATH_TO_SERVER"
     }

4. Add a PhoenixMsg tag to your Msg type

   type Msg
     = UpdateSomething
     | DoSomethingElse
     | PhoenixMsg (Phoenix.Socket.Msg Msg)
   

5. Add the following to your update function

   PhoenixMsg msg ->
     let
       ( phxSocket, phxCmd ) = Phoenix.Socket.update msg model.phxSocket
     in
       ( { model | phxSocket = phxSocket }
       , Cmd.map PhoenixMsg phxCmd
       )

6. Listen for messages

   subscriptions : Model -> Sub Msg
   subscriptions model =
     Phoenix.Socket.listen model.phxSocket PhoenixMsg

Take a look at examples/Chat.elm if you want to see an example.

Contributing

Pull requests and issues are greatly appreciated! If you think there's a better way to implement this library, I'd love to hear your feedback. I basically tried to model this library after the official javascript one, but that may not be the best approach.