Merge pull request #114460 from brianpursley/pf-exit

portforward: return error on lost connection to pod

Kubernetes-commit: 61cdb86814489624dd5a169526797e186a118e66

tools/portforward/portforward.go

@@ -37,6 +37,8 @@ import (
 // TODO move to API machinery and re-unify with kubelet/server/portfoward
 const PortForwardProtocolV1Name = "portforward.k8s.io"
 
+var ErrLostConnectionToPod = errors.New("lost connection to pod")
+
 // PortForwarder knows how to listen for local connections and forward them to
 // a remote pod via an upgraded HTTP request.
 type PortForwarder struct {
@@ -230,7 +232,7 @@ func (pf *PortForwarder) forward() error {
 	select {
 	case <-pf.stopChan:
 	case <-pf.streamConn.CloseChan():
-		runtime.HandleError(errors.New("lost connection to pod"))
+		return ErrLostConnectionToPod
 	}
 
 	return nil

tools/portforward/portforward_test.go

@@ -567,3 +567,64 @@ func TestWaitForConnectionExitsOnStreamConnClosed(t *testing.T) {
 	port := ForwardedPort{}
 	pf.waitForConnection(&listener, port)
 }
+
+func TestForwardPortsReturnsErrorWhenConnectionIsLost(t *testing.T) {
+	dialer := &fakeDialer{
+		conn: newFakeConnection(),
+	}
+
+	stopChan := make(chan struct{})
+	readyChan := make(chan struct{})
+	errChan := make(chan error)
+
+	pf, err := New(dialer, []string{":5000"}, stopChan, readyChan, os.Stdout, os.Stderr)
+	if err != nil {
+		t.Fatalf("failed to create new PortForwarder: %s", err)
+	}
+
+	go func() {
+		errChan <- pf.ForwardPorts()
+	}()
+
+	<-pf.Ready
+
+	// Simulate lost pod connection by closing streamConn, which should result in pf.ForwardPorts() returning an error.
+	pf.streamConn.Close()
+
+	err = <-errChan
+	if err == nil {
+		t.Fatalf("unexpected non-error from pf.ForwardPorts()")
+	} else if err != ErrLostConnectionToPod {
+		t.Fatalf("unexpected error from pf.ForwardPorts(): %s", err)
+	}
+}
+
+func TestForwardPortsReturnsNilWhenStopChanIsClosed(t *testing.T) {
+	dialer := &fakeDialer{
+		conn: newFakeConnection(),
+	}
+
+	stopChan := make(chan struct{})
+	readyChan := make(chan struct{})
+	errChan := make(chan error)
+
+	pf, err := New(dialer, []string{":5000"}, stopChan, readyChan, os.Stdout, os.Stderr)
+	if err != nil {
+		t.Fatalf("failed to create new PortForwarder: %s", err)
+	}
+
+	go func() {
+		errChan <- pf.ForwardPorts()
+	}()
+
+	<-pf.Ready
+
+	// Closing (or sending to) stopChan indicates a stop request by the caller, which should result in pf.ForwardPorts()
+	// returning nil.
+	close(stopChan)
+
+	err = <-errChan
+	if err != nil {
+		t.Fatalf("unexpected error from pf.ForwardPorts(): %s", err)
+	}
+}