send messages with select to avoid deadlocks

Fixes #287.

go.mod

@@ -1,9 +1,9 @@
 module github.com/chromedp/chromedp
 
 require (
-	github.com/chromedp/cdproto v0.0.0-20190217000753-2d8e8962ceb2
+	github.com/chromedp/cdproto v0.0.0-20190327003620-8d5e1d04ce19
 	github.com/disintegration/imaging v1.6.0
 	github.com/gorilla/websocket v1.4.0
-	github.com/mailru/easyjson v0.0.0-20190221075403-6243d8e04c3f
+	github.com/mailru/easyjson v0.0.0-20190312143242-1de009706dbe
 	golang.org/x/image v0.0.0-20190220214146-31aff87c08e9 // indirect
 )

go.sum

@@ -1,5 +1,5 @@
-github.com/chromedp/cdproto v0.0.0-20190217000753-2d8e8962ceb2 h1:4Ck8YOuS0G3+0xMb80cDSff7QpUolhSc0PGyfagbcdA=
-github.com/chromedp/cdproto v0.0.0-20190217000753-2d8e8962ceb2/go.mod h1:xquOK9dIGFlLaIGI4c6IyfLI/Gz0LiYYuJtzhsUODgI=
+github.com/chromedp/cdproto v0.0.0-20190327003620-8d5e1d04ce19 h1:KOdZXVcB8L3zR4ZsMAnviYJFIgfRP/iYSEzXl7rYXhc=
+github.com/chromedp/cdproto v0.0.0-20190327003620-8d5e1d04ce19/go.mod h1:xquOK9dIGFlLaIGI4c6IyfLI/Gz0LiYYuJtzhsUODgI=
 github.com/disintegration/imaging v1.6.0 h1:nVPXRUUQ36Z7MNf0O77UzgnOb1mkMMor7lmJMJXc/mA=
 github.com/disintegration/imaging v1.6.0/go.mod h1:xuIt+sRxDFrHS0drzXUlCJthkJ8k7lkkUojDSR247MQ=
 github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
@@ -7,8 +7,8 @@ github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoA
 github.com/knq/sysutil v0.0.0-20181215143952-f05b59f0f307 h1:vl4eIlySbjertFaNwiMjXsGrFVK25aOWLq7n+3gh2ls=
 github.com/knq/sysutil v0.0.0-20181215143952-f05b59f0f307/go.mod h1:BjPj+aVjl9FW/cCGiF3nGh5v+9Gd3VCgBQbod/GlMaQ=
 github.com/mailru/easyjson v0.0.0-20180823135443-60711f1a8329/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
-github.com/mailru/easyjson v0.0.0-20190221075403-6243d8e04c3f h1:B6PQkurxGG1rqEX96oE14gbj8bqvYC5dtks9r5uGmlE=
-github.com/mailru/easyjson v0.0.0-20190221075403-6243d8e04c3f/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
+github.com/mailru/easyjson v0.0.0-20190312143242-1de009706dbe h1:W/GaMY0y69G4cFlmsC6B9sbuo2fP8OFP1ABjt4kPz+w=
+github.com/mailru/easyjson v0.0.0-20190312143242-1de009706dbe/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
 golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81 h1:00VmoueYNlNz/aHIilyyQz/MHSqGoWJzpFv/HW8xpzI=
 golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81/go.mod h1:ux5Hcp/YLpHSI86hEcLt0YII63i6oz57MZXIpbrjZUs=
 golang.org/x/image v0.0.0-20190220214146-31aff87c08e9 h1:+vH8qNweCrORN49012OX3h0oWEXO3p+rRnpAGQinddk=

handler.go

@@ -155,10 +155,18 @@ func (h *TargetHandler) run(ctxt context.Context) {
 
 				switch {
 				case msg.Method != "":
-					h.qevents <- msg
+					select {
+					case h.qevents <- msg:
+					case <-ctxt.Done():
+						return
+					}
 
 				case msg.ID != 0:
-					h.qres <- msg
+					select {
+					case h.qres <- msg:
+					case <-ctxt.Done():
+						return
+					}
 
 				default:
 					h.errf("ignoring malformed incoming message (missing id or method): %#v", msg)
@@ -226,6 +234,15 @@ func (h *TargetHandler) processEvent(ctxt context.Context, msg *cdproto.Message)
 	if msg == nil {
 		return ErrChannelClosed
 	}
+	switch msg.Method {
+	case "Page.frameClearedScheduledNavigation",
+		"Page.frameScheduledNavigation":
+		// These events are now deprecated, and UnmarshalMessage panics
+		// when they are received from Chrome. For now, to avoid panics
+		// and compile errors, and to fix chromedp v0 when installed via
+		// 'go get -u', skip the events here.
+		return nil
+	}
 
 	// unmarshal
 	ev, err := cdproto.UnmarshalMessage(msg)
@@ -346,10 +363,14 @@ func (h *TargetHandler) Execute(ctxt context.Context, methodType string, params
 	h.resrw.Unlock()
 
 	// queue message
-	h.qcmd <- &cdproto.Message{
+	select {
+	case h.qcmd <- &cdproto.Message{
 		ID:     id,
 		Method: cdproto.MethodType(methodType),
 		Params: paramsBuf,
+	}:
+	case <- ctxt.Done():
+		return ctxt.Err()
 	}
 
 	errch := make(chan error, 1)
@@ -530,13 +551,9 @@ func (h *TargetHandler) pageEvent(ctxt context.Context, ev interface{}) {
 	case *page.EventFrameStoppedLoading:
 		id, op = e.FrameID, frameStoppedLoading
 
-	case *page.EventFrameScheduledNavigation:
-		id, op = e.FrameID, frameScheduledNavigation
-
-	case *page.EventFrameClearedScheduledNavigation:
-		id, op = e.FrameID, frameClearedScheduledNavigation
-
 		// ignored events
+	case *page.EventFrameRequestedNavigation:
+		return
 	case *page.EventDomContentEventFired:
 		return
 	case *page.EventLoadEventFired:

runner/runner.go

@@ -213,7 +213,8 @@ func (r *Runner) Start(ctxt context.Context, opts ...string) error {
 	return nil
 }
 
-// Shutdown shuts down the Chrome process.
+// Shutdown shuts down the Chrome process.  Currently only has support for
+// SIGTERM in darwin and linux systems
 func (r *Runner) Shutdown(ctxt context.Context, opts ...client.Option) error {
 	var err error
 
@@ -241,12 +242,15 @@ func (r *Runner) Shutdown(ctxt context.Context, opts ...client.Option) error {
 		}
 	}
 
-	// osx applications do not automatically exit when all windows (ie, tabs)
+	// osx and linux applications do not automatically exit when all windows (ie, tabs)
 	// closed, so send SIGTERM.
 	//
 	// TODO: add other behavior here for more process options on shutdown?
-	if runtime.GOOS == "darwin" && r.cmd != nil && r.cmd.Process != nil {
-		return r.cmd.Process.Signal(syscall.SIGTERM)
+	if r.cmd != nil && r.cmd.Process != nil {
+		switch runtime.GOOS {
+		case "darwin", "linux":
+			return r.cmd.Process.Signal(syscall.SIGTERM)
+		}
 	}
 
 	return nil