move implementation to internal/ directory (#828)

internal/rpc/versionhandshake/versionhandshake_transport_wrappers.go

@@ -0,0 +1,68 @@
+package versionhandshake
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"github.com/zrepl/zrepl/internal/transport"
+)
+
+type HandshakeConnecter struct {
+	connecter transport.Connecter
+	timeout   time.Duration
+}
+
+func (c HandshakeConnecter) Connect(ctx context.Context) (transport.Wire, error) {
+	conn, err := c.connecter.Connect(ctx)
+	if err != nil {
+		return nil, err
+	}
+	dl, ok := ctx.Deadline()
+	if !ok {
+		dl = time.Now().Add(c.timeout)
+	}
+	if err := DoHandshakeCurrentVersion(conn, dl); err != nil {
+		conn.Close()
+		return nil, err
+	}
+	return conn, nil
+}
+
+func Connecter(connecter transport.Connecter, timeout time.Duration) HandshakeConnecter {
+	return HandshakeConnecter{
+		connecter: connecter,
+		timeout:   timeout,
+	}
+}
+
+// wrapper type that performs a a protocol version handshake before returning the connection
+type HandshakeListener struct {
+	l       transport.AuthenticatedListener
+	timeout time.Duration
+}
+
+func (l HandshakeListener) Addr() net.Addr { return l.l.Addr() }
+
+func (l HandshakeListener) Close() error { return l.l.Close() }
+
+func (l HandshakeListener) Accept(ctx context.Context) (*transport.AuthConn, error) {
+	conn, err := l.l.Accept(ctx)
+	if err != nil {
+		return nil, err
+	}
+	dl, ok := ctx.Deadline()
+	if !ok {
+		dl = time.Now().Add(l.timeout) // shadowing
+	}
+	if err := DoHandshakeCurrentVersion(conn, dl); err != nil {
+		err.isAcceptError = true
+		conn.Close()
+		return nil, err
+	}
+	return conn, nil
+}
+
+func Listener(l transport.AuthenticatedListener, timeout time.Duration) transport.AuthenticatedListener {
+	return HandshakeListener{l, timeout}
+}