// Asks the message writer to write the error message to its websocket and terminate
// This function waits on a message from the closeChan to ensure that
func (msgWriter *W) ErrorAndClose(tId uint, uId, errMsg string) {
logutil.Log(tId, uId, "Connection Terminated: "+errMsg)
closeChan := make(chan bool, 1)
sd := &shutdown{closeChan, msgdef.NewServerError(tId, uId, errMsg)}
msgWriter.shutdownChan <- sd
<-closeChan
logutil.Log(tId, uId, "Close Confirmation Received")
}
// Writes the contents of sMsg back to ws, returning any errors encountered
func writeback(ws *websocket.Conn, sMsg *msgdef.ServerMsg) error {
msg := sMsg.Msg
bytes, err := json.Marshal(msg)
if err != nil {
return err
}
logutil.Log(sMsg.TId, sMsg.UId, fmt.Sprintf("Server Sent: %s", bytes))
_, err = ws.Write(bytes)
return err
}
// Loops listening for messages to write back to msgWriter's websocket
// There are two possible messages to receive
// 1: Server message
// The contents of the server message is marshalled and written back to the websocket
// If an error occurs the error is logged and written back to the websocket
// Loop continues
// 2: shutdown message
// The contents of the shutdown message's server message is marshalled and written back to the websocket
// If an error occurs the error is logged and written back to the websocket
// shutdown messages closeChan is sent a value, allowing the sender to unblock
// Loop terminates
func (msgWriter *W) listenAndWriteback() {
for {
var sMsg *msgdef.ServerMsg
var closeChan chan bool
select {
case sMsg = <-msgWriter.msgChan:
case sd := <-msgWriter.shutdownChan:
sMsg = sd.errMsg
closeChan = sd.closeChan
}
if err := writeback(msgWriter.ws, sMsg); err != nil {
logutil.Log(sMsg.TId, sMsg.UId, err.Error())
}
if closeChan != nil {
logutil.Log(sMsg.TId, sMsg.UId, "Error message received - Shutting Down")
closeChan <- true
return
}
}
}
// Unmarshals a websocket message into msgi as JSON.
func UnmarshalAndLog(tId uint, uId string, ws *websocket.Conn, msg interface{}) error {
var data string
if err := websocket.Message.Receive(ws, &data); err != nil {
return err
}
logutil.Log(tId, uId, data)
if err := json.Unmarshal([]byte(data), msg); err != nil {
return err
}
return nil
}
func processMsg(tId uint, msg *msgdef.CMsgMsg, usr *user.U) func() error {
return func() error {
if msg.Op != msgdef.CMsgOp {
return errors.New("Incorrect op-code for msg: " + string(msg.Op))
}
if err := msg.Validate(); err != nil {
return err
}
if idMap.Contains(msg.To) {
forUser := idMap.Get(msg.To).(*user.U)
safeContent := jsonutil.SanitiseJSON(msg.Content)
msgMsg := &msgdef.SMsgMsg{Op: msgdef.SMsgOp, From: usr.Id, Content: safeContent}
sMsg := &msgdef.ServerMsg{Msg: msgMsg, TId: tId, UId: usr.Id}
forUser.MsgWriter.WriteMsg(sMsg)
logutil.Log(tId, usr.Id, fmt.Sprintf("Content: '%s' sent to: '%s'", msg.Content, msg.To))
} else {
nuMsg := &msgdef.SMsgMsg{Op: msgdef.SNotUserOp, From: msg.To, Content: fmt.Sprintf("User: %s was not found", msg.To)}
sMsg := &msgdef.ServerMsg{Msg: nuMsg, TId: tId, UId: usr.Id}
usr.MsgWriter.WriteMsg(sMsg)
}
return nil
}
}
// Logs a task involving an old and new location point
func locLogL(tId uint, uId, taskDesc string, oMNS, oMEW, nMNS, nMEW float64) {
logutil.Log(tId, uId, fmt.Sprintf("%s - oMNS: %f oMEW %f nMNS: %f nMEW %f", taskDesc, oMNS, oMEW, nMNS, nMEW))
}
// Logs a task involving only a single location point
func locLog(tId uint, uId, taskDesc string, mNS, mEW float64) {
logutil.Log(tId, uId, fmt.Sprintf("%s - mNS: %f mEW: %f", taskDesc, mNS, mEW))
}