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//
// rhctl
//
// Copyright (C) 2009-2016 Christian Pointner <equinox@helsinki.at>
//
// This file is part of rhctl.
//
// rhctl is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// rhctl is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with rhctl. If not, see <http://www.gnu.org/licenses/>.
//
package main
import (
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"github.com/gorilla/websocket"
)
type webSocketRequestData struct {
Command string `json:"COMMAND"`
}
type webSocketResponseBaseData struct {
ResponseCode int `json:"RESPONSE_CODE"`
Type string `json:"TYPE"`
ErrorString string `json:"ERROR_STRING"`
}
type webSocketResponseStateData struct {
webSocketResponseBaseData
State State `json:"STATE"`
}
func sendWebSocketResponse(ws *websocket.Conn, rd interface{}) {
if err := ws.WriteJSON(rd); err != nil {
rhdl.Println("Web(socket) client", ws.RemoteAddr(), "write error:", err)
}
}
func sendWebSocketErrorResponse(ws *websocket.Conn, code int, errStr string) {
rd := &webSocketResponseBaseData{}
rd.ResponseCode = code
rd.Type = "error"
rd.ErrorString = errStr
sendWebSocketResponse(ws, rd)
}
func sendWebSocketStateResponse(ws *websocket.Conn, state State) {
rd := &webSocketResponseStateData{}
rd.ResponseCode = http.StatusOK
rd.Type = "state"
rd.ErrorString = "OK"
sendWebSocketResponse(ws, rd)
}
func webSocketSessionHandler(reqchan <-chan webSocketRequestData, ws *websocket.Conn, ctrl *SwitchControl) {
defer ws.Close()
for {
select {
case reqdata, ok := <-reqchan:
if !ok {
return
}
switch reqdata.Command {
case "state":
resp := make(chan interface{})
ctrl.Commands <- &Command{Type: CmdState, Response: resp}
result := <-resp
switch result.(type) {
case State:
sendWebSocketStateResponse(ws, result.(State))
case error:
sendWebSocketErrorResponse(ws, http.StatusInternalServerError, result.(error).Error())
default:
sendWebSocketErrorResponse(ws, http.StatusInternalServerError, fmt.Sprintf("invalid response of type %T: %+v", result, result))
}
default:
sendWebSocketErrorResponse(ws, http.StatusBadRequest, fmt.Sprintf("unknown command '%s'", reqdata.Command))
}
}
}
}
func webSocketHandler(ctrl *SwitchControl, w http.ResponseWriter, r *http.Request) {
ws, err := websocket.Upgrade(w, r, nil, 64*1024, 64*1024)
if _, ok := err.(websocket.HandshakeError); ok {
http.Error(w, "Not a websocket handshake", 400)
return
} else if err != nil {
rhdl.Println("Web(socket) client", ws.RemoteAddr(), "error:", err)
return
}
rhdl.Println("Web(socket) client", ws.RemoteAddr(), "connected")
reqchan := make(chan webSocketRequestData)
go webSocketSessionHandler(reqchan, ws, ctrl)
defer close(reqchan)
for {
t, r, err := ws.NextReader()
if err != nil {
rhdl.Println("Web(socket) Client", ws.RemoteAddr(), "disconnected:", err)
return
}
switch t {
case websocket.TextMessage:
var reqdata webSocketRequestData
if err := json.NewDecoder(r).Decode(&reqdata); err != nil {
if err == io.EOF {
err = io.ErrUnexpectedEOF
}
rhdl.Println("Web(socket) client", ws.RemoteAddr(), "request error:", err)
sendWebSocketErrorResponse(ws, http.StatusBadRequest, err.Error())
return
}
// rhdl.Printf("Web(socket) client %s got: %+v", ws.RemoteAddr(), reqdata)
reqchan <- reqdata
case websocket.BinaryMessage:
sendWebSocketErrorResponse(ws, http.StatusBadRequest, "binary messages are not allowed")
io.Copy(ioutil.Discard, r) // consume all the data
}
}
}
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