hexmap/server/websocket/shared.go

package websocket

import "go.uber.org/zap/zapcore"

// StatusCode is the code used by the WebSocket protocol to signal the other side on close.
type StatusCode int16

const (
	StatusNormal                   StatusCode = 1000
	StatusGoingAway                StatusCode = 1001
	StatusProtocolError            StatusCode = 1002
	StatusTooBig                   StatusCode = 1009
	StatusProtocolVersionOutOfDate StatusCode = 4000

	GoodbyeType = "GOODBYE"
)

// TODO: Noting that there should be three channels in play:
//     1) Reader to client: to receive messages from the connection
//     2) Client to writer: to send messages on the connection
//     3) Writer to reader: indicating that it is about to send a close message, and the reader should wait for one and
//        time out the connection if it takes too long.

// SocketClosed is synthesized when a client closes the WebSocket connection, or sent to the write process to write a
// WebSocket close message.
// Sending a SocketClosed on a channel causes that channel to be closed right after.
type SocketClosed struct {
	// Code is the StatusCode given (or which should be given) in the close message.
	Code StatusCode
	// Text is the reason text given (or which should be given) in the close message. Max 123 characters.
	Text string
	// Error may be an error that resulted in the closure of the socket.
	// Will not be written by the writer; only useful when it's returned from the reader.
	Error error
}

func (c SocketClosed) MarshalLogObject(encoder zapcore.ObjectEncoder) error {
	encoder.AddString("type", GoodbyeType)
	encoder.AddInt16("code", int16(c.Code))
	encoder.AddString("text", c.Text)
	if c.Error != nil {
		encoder.AddString("error", c.Error.Error())
	}
	return nil
}

func (c SocketClosed) ClientType() ClientMessageType {
	return ClientGoodbyeType
}

func (c SocketClosed) ServerType() ServerMessageType {
	return ServerGoodbyeType
}