rpc: close outgoing SSH connection on exit.

cmd/main.go

@@ -208,6 +208,8 @@ func doPull(pull Pull, c *cli.Context, log jobrun.Logger) (err error) {
 		return
 	}
 
+	defer remote.Close()
+
 	fsr := rpc.FilesystemRequest{
 		Direction: rpc.DirectionPull,
 	}

rpc/rpc.go

@@ -8,6 +8,7 @@ import (
 	. "github.com/zrepl/zrepl/util"
 	"github.com/zrepl/zrepl/zfs"
 	"io"
+	"os"
 	"reflect"
 )
 
@@ -16,6 +17,8 @@ type RPCRequester interface {
 	FilesystemVersionsRequest(r FilesystemVersionsRequest) (versions []zfs.FilesystemVersion, err error)
 	InitialTransferRequest(r InitialTransferRequest) (io.Reader, error)
 	IncrementalTransferRequest(r IncrementalTransferRequest) (io.Reader, error)
+	CloseRequest(r CloseRequest) (err error)
+	ForceClose() (err error)
 }
 
 type RPCHandler interface {
@@ -129,6 +132,25 @@ func ListenByteStreamRPC(conn ByteStream, handler RPCHandler, log Logger) error
 			}
 			send(&r)
 
+		case RTCloseRequest:
+
+			var rq CloseRequest
+			if err := recv(&rq); err != nil {
+				sendError(EDecodeRequestBody, err.Error())
+				return conn.Close()
+			}
+
+			if rq.Goodbye != "" {
+				log.Printf("close request with goodbye: %s", rq.Goodbye)
+			}
+
+			send(&ResponseHeader{
+				RequestId:    header.Id,
+				ResponseType: ROK,
+			})
+
+			return conn.Close()
+
 		case RTFilesystemRequest:
 
 			var rq FilesystemRequest
@@ -271,6 +293,8 @@ func inferRequestType(v interface{}) (RequestType, error) {
 		return RTInitialTransferRequest, nil
 	case IncrementalTransferRequest:
 		return RTIncrementalTransferRequest, nil
+	case CloseRequest:
+		return RTCloseRequest, nil
 	default:
 		return 0, errors.New(fmt.Sprintf("cannot infer request type for type '%v'",
 			reflect.TypeOf(v)))
@@ -383,6 +407,19 @@ func (c ByteStreamRPC) IncrementalTransferRequest(r IncrementalTransferRequest)
 	return
 }
 
+func (c ByteStreamRPC) CloseRequest(r CloseRequest) (err error) {
+	if err = c.sendRequestReceiveHeader(r, ROK); err != nil {
+		return
+	}
+	os.Stderr.WriteString("close request conn.Close()")
+	err = c.conn.Close()
+	return
+}
+
+func (c ByteStreamRPC) ForceClose() (err error) {
+	return c.conn.Close()
+}
+
 type LocalRPC struct {
 	handler RPCHandler
 }
@@ -407,3 +444,7 @@ func (c LocalRPC) IncrementalTransferRequest(r IncrementalTransferRequest) (read
 	reader, err = c.handler.HandleIncrementalTransferRequest(r)
 	return
 }
+
+func (c LocalRPC) CloseRequest(r CloseRequest) error { return nil }
+
+func (c LocalRPC) ForceClose() error { return nil }

rpc/structs.go

@@ -12,6 +12,7 @@ const (
 	RTFilesystemVersionsRequest              = 0x11
 	RTInitialTransferRequest                 = 0x12
 	RTIncrementalTransferRequest             = 0x13
+	RTCloseRequest                           = 0x20
 )
 
 type RequestHeader struct {
@@ -58,6 +59,10 @@ type ByteStreamRPCProtocolVersionRequest struct {
 	ClientVersion uint8
 }
 
+type CloseRequest struct {
+	Goodbye string
+}
+
 type ErrorId uint8
 
 const (