tools: rewrite benchmark tool

tools/benchmark/cmd/util.go

@@ -0,0 +1,42 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 cmd
+
+import (
+	"crypto/rand"
+	"fmt"
+	"os"
+
+	"github.com/coreos/etcd/Godeps/_workspace/src/google.golang.org/grpc"
+)
+
+func mustCreateConn() *grpc.ClientConn {
+	conn, err := grpc.Dial(endpoints)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "dial error: %v\n", err)
+		os.Exit(1)
+	}
+	return conn
+}
+
+func mustRandBytes(n int) []byte {
+	rb := make([]byte, n)
+	_, err := rand.Read(rb)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to generate value: %v\n", err)
+		os.Exit(1)
+	}
+	return rb
+}