diff --git a/vendor/google.golang.org/grpc/trace.go b/vendor/google.golang.org/grpc/trace.go
new file mode 100644
index 0000000..0a57b99
--- /dev/null
+++ b/vendor/google.golang.org/grpc/trace.go
@@ -0,0 +1,126 @@
+/*
+ *
+ * Copyright 2015 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpc
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/net/trace"
+)
+
+// EnableTracing controls whether to trace RPCs using the golang.org/x/net/trace package.
+// This should only be set before any RPCs are sent or received by this program.
+var EnableTracing bool
+
+// methodFamily returns the trace family for the given method.
+// It turns "/pkg.Service/GetFoo" into "pkg.Service".
+func methodFamily(m string) string {
+	m = strings.TrimPrefix(m, "/") // remove leading slash
+	if i := strings.Index(m, "/"); i >= 0 {
+		m = m[:i] // remove everything from second slash
+	}
+	if i := strings.LastIndex(m, "."); i >= 0 {
+		m = m[i+1:] // cut down to last dotted component
+	}
+	return m
+}
+
+// traceInfo contains tracing information for an RPC.
+type traceInfo struct {
+	tr        trace.Trace
+	firstLine firstLine
+}
+
+// firstLine is the first line of an RPC trace.
+// It may be mutated after construction; remoteAddr specifically may change
+// during client-side use.
+type firstLine struct {
+	mu         sync.Mutex
+	client     bool // whether this is a client (outgoing) RPC
+	remoteAddr net.Addr
+	deadline   time.Duration // may be zero
+}
+
+func (f *firstLine) SetRemoteAddr(addr net.Addr) {
+	f.mu.Lock()
+	f.remoteAddr = addr
+	f.mu.Unlock()
+}
+
+func (f *firstLine) String() string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	var line bytes.Buffer
+	io.WriteString(&line, "RPC: ")
+	if f.client {
+		io.WriteString(&line, "to")
+	} else {
+		io.WriteString(&line, "from")
+	}
+	fmt.Fprintf(&line, " %v deadline:", f.remoteAddr)
+	if f.deadline != 0 {
+		fmt.Fprint(&line, f.deadline)
+	} else {
+		io.WriteString(&line, "none")
+	}
+	return line.String()
+}
+
+const truncateSize = 100
+
+func truncate(x string, l int) string {
+	if l > len(x) {
+		return x
+	}
+	return x[:l]
+}
+
+// payload represents an RPC request or response payload.
+type payload struct {
+	sent bool        // whether this is an outgoing payload
+	msg  interface{} // e.g. a proto.Message
+	// TODO(dsymonds): add stringifying info to codec, and limit how much we hold here?
+}
+
+func (p payload) String() string {
+	if p.sent {
+		return truncate(fmt.Sprintf("sent: %v", p.msg), truncateSize)
+	}
+	return truncate(fmt.Sprintf("recv: %v", p.msg), truncateSize)
+}
+
+type fmtStringer struct {
+	format string
+	a      []interface{}
+}
+
+func (f *fmtStringer) String() string {
+	return fmt.Sprintf(f.format, f.a...)
+}
+
+type stringer string
+
+func (s stringer) String() string { return string(s) }