WebSocket.hs

{-# LANGUAGE CPP                        #-}
{-# LANGUAGE DeriveGeneric              #-}
{-# LANGUAGE ScopedTypeVariables        #-}
{-# LANGUAGE OverloadedStrings          #-}
{-# LANGUAGE RankNTypes                 #-}
{-# LANGUAGE LambdaCase                 #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  Miso.WebSocket
-- Copyright   :  (C) 2016-2018 David M. Johnson
-- License     :  BSD3-style (see the file LICENSE)
-- Maintainer  :  David M. Johnson <djohnson.m@gmail.com>
-- Stability   :  experimental
-- Portability :  non-portable
----------------------------------------------------------------------------
module Miso.WebSocket
  ( -- * Types
    WebSocket   (..)
  , URL         (..)
  , Protocols   (..)
  , SocketState (..)
  , CloseCode   (..)
  , WasClean    (..)
  , Reason      (..)
  ) where

import GHC.Generics
import Prelude                hiding (map)
#ifdef ghcjs_HOST_OS
import GHCJS.Marshal
#endif

import Miso.String

-- | WebSocket connection messages
data WebSocket action
  = WebSocketMessage action
  | WebSocketClose CloseCode WasClean Reason
  | WebSocketOpen
  | WebSocketError MisoString
    deriving (Show, Eq)

-- | URL of Websocket server
newtype URL = URL MisoString
  deriving (Show, Eq)

-- | Protocols for Websocket connection
newtype Protocols = Protocols [MisoString]
  deriving (Show, Eq)

-- | Wether or not the connection closed was done so cleanly
newtype WasClean = WasClean Bool deriving (Show, Eq)

-- | Reason for closed connection
newtype Reason = Reason MisoString deriving (Show, Eq)

-- | `SocketState` corresponding to current WebSocket connection
data SocketState
  = CONNECTING -- ^ 0
  | OPEN       -- ^ 1
  | CLOSING    -- ^ 2
  | CLOSED     -- ^ 3
  deriving (Show, Eq, Ord, Enum)

-- | Code corresponding to a closed connection
-- https://developer.mozilla.org/en-US/docs/Web/API/CloseEvent
data CloseCode
  = CLOSE_NORMAL
   -- ^ 1000, Normal closure; the connection successfully completed whatever purpose for which it was created.
  | CLOSE_GOING_AWAY
   -- ^ 1001, The endpoint is going away, either because of a server failure or because the browser is navigating away from the page that opened the connection.
  | CLOSE_PROTOCOL_ERROR
   -- ^ 1002, The endpoint is terminating the connection due to a protocol error.
  | CLOSE_UNSUPPORTED
   -- ^ 1003, The connection is being terminated because the endpoint received data of a type it cannot accept (for example, a textonly endpoint received binary data).
  | CLOSE_NO_STATUS
   -- ^ 1005, Reserved.  Indicates that no status code was provided even though one was expected.
  | CLOSE_ABNORMAL
   -- ^ 1006, Reserved. Used to indicate that a connection was closed abnormally (that is, with no close frame being sent) when a status code is expected.
  | Unsupported_Data
   -- ^ 1007, The endpoint is terminating the connection because a message was received that contained inconsistent data (e.g., nonUTF8 data within a text message).
  | Policy_Violation
   -- ^ 1008, The endpoint is terminating the connection because it received a message that violates its policy. This is a generic status code, used when codes 1003 and 1009 are not suitable.
  | CLOSE_TOO_LARGE
   -- ^ 1009, The endpoint is terminating the connection because a data frame was received that is too large.
  | Missing_Extension
   -- ^ 1010, The client is terminating the connection because it expected the server to negotiate one or more extension, but the server didn't.
  | Internal_Error
   -- ^ 1011, The server is terminating the connection because it encountered an unexpected condition that prevented it from fulfilling the request.
  | Service_Restart
   -- ^ 1012, The server is terminating the connection because it is restarting.
  | Try_Again_Later
   -- ^ 1013, The server is terminating the connection due to a temporary condition, e.g. it is overloaded and is casting off some of its clients.
  | TLS_Handshake
   -- ^ 1015, Reserved. Indicates that the connection was closed due to a failure to perform a TLS handshake (e.g., the server certificate can't be verified).
  | OtherCode Int
   -- ^ OtherCode that is reserved and not in the range 0999
  deriving (Show, Eq, Generic)

#ifdef ghcjs_HOST_OS
-- Defined here to avoid an orphan instance
instance ToJSVal CloseCode
instance FromJSVal CloseCode
#endif