From 24893bf740d2d80386c107c14f7580b6fffab3ec Mon Sep 17 00:00:00 2001
From: Austin <acmacalister@gmail.com>
Date: Tue, 13 Oct 2015 19:07:54 -0700
Subject: [PATCH] removed panics, cleaned up leaking ticker routine
---
middleware/websocket/websocket.go | 39 +++++++++++++++++++------------
1 file changed, 24 insertions(+), 15 deletions(-)
diff --git a/middleware/websocket/websocket.go b/middleware/websocket/websocket.go
index 9f3ffe14b..f344fe511 100644
--- a/middleware/websocket/websocket.go
+++ b/middleware/websocket/websocket.go
@@ -83,35 +83,35 @@ func serveWS(w http.ResponseWriter, r *http.Request, config *Config) (int, error
}
conn, err := upgrader.Upgrade(w, r, nil)
if err != nil {
- return 0, err
+ return http.StatusBadRequest, err
}
defer conn.Close()
cmd := exec.Command(config.Command, config.Arguments...)
stdout, err := cmd.StdoutPipe()
if err != nil {
- panic(err) // TODO
+ return http.StatusBadGateway, err
}
stdin, err := cmd.StdinPipe()
if err != nil {
- panic(err) // TODO
+ return http.StatusBadGateway, err
}
metavars, err := buildEnv(cmd.Path, r)
if err != nil {
- panic(err) // TODO
+ return http.StatusBadGateway, err
}
cmd.Env = metavars
if err := cmd.Start(); err != nil {
- panic(err)
+ return http.StatusBadGateway, err
}
reader(conn, stdout, stdin)
- return 0, nil // we shouldn't get here.
+ return 0, nil
}
// buildEnv creates the meta-variables for the child process according
@@ -171,32 +171,39 @@ func reader(conn *websocket.Conn, stdout io.ReadCloser, stdin io.WriteCloser) {
conn.SetReadLimit(maxMessageSize)
conn.SetReadDeadline(time.Now().Add(pongWait))
conn.SetPongHandler(func(string) error { conn.SetReadDeadline(time.Now().Add(pongWait)); return nil })
- go ticker(conn)
+ tickerChan := make(chan bool)
+ defer func() { tickerChan <- true }() // make sure to close the ticker when we are done.
+ go ticker(conn, tickerChan)
for {
msgType, r, err := conn.NextReader()
if err != nil {
if msgType == -1 {
- return // we are done, as we got a close method.
+ return // we got a disconnect from the client. We are good to close.
}
- panic(err) // TODO do something else here.
+ conn.WriteControl(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseGoingAway, ""), time.Time{})
+ return
}
w, err := conn.NextWriter(msgType)
if err != nil {
- panic(err) // TODO do something else here.
+ conn.WriteControl(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseGoingAway, ""), time.Time{})
+ return
}
if _, err := io.Copy(stdin, r); err != nil {
- panic(err) // TODO do something else here.
+ conn.WriteControl(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseGoingAway, ""), time.Time{})
+ return
}
go func() {
if _, err := io.Copy(w, stdout); err != nil {
- panic(err) // TODO do something else here.
+ conn.WriteControl(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseGoingAway, ""), time.Time{})
+ return
}
if err := w.Close(); err != nil {
- panic(err) // TODO do something else here.
+ conn.WriteControl(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseGoingAway, ""), time.Time{})
+ return
}
}()
}
@@ -204,17 +211,19 @@ func reader(conn *websocket.Conn, stdout io.ReadCloser, stdin io.WriteCloser) {
// ticker is start by the reader. Basically it is the method that simulates the websocket
// between the server and client to keep it alive with ping messages.
-func ticker(conn *websocket.Conn) {
+func ticker(conn *websocket.Conn, c chan bool) {
ticker := time.NewTicker(pingPeriod)
defer func() {
ticker.Stop()
- conn.WriteMessage(websocket.CloseMessage, nil)
+ close(c)
}()
for { // blocking loop with select to wait for stimulation.
select {
case <-ticker.C:
conn.WriteMessage(websocket.PingMessage, nil)
+ case <-c:
+ return // clean up this routine.
}
}
}