add vendoring with go dep

vendor/github.com/vmware/govmomi/govc/metric/performance.go

@@ -0,0 +1,96 @@
+/*
+Copyright (c) 2017 VMware, Inc. All Rights Reserved.
+
+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 metric
+
+import (
+	"context"
+	"flag"
+	"fmt"
+
+	"github.com/vmware/govmomi/govc/flags"
+	"github.com/vmware/govmomi/performance"
+)
+
+type PerformanceFlag struct {
+	*flags.DatacenterFlag
+	*flags.OutputFlag
+
+	m *performance.Manager
+
+	interval int
+}
+
+func NewPerformanceFlag(ctx context.Context) (*PerformanceFlag, context.Context) {
+	f := &PerformanceFlag{}
+	f.DatacenterFlag, ctx = flags.NewDatacenterFlag(ctx)
+	f.OutputFlag, ctx = flags.NewOutputFlag(ctx)
+	return f, ctx
+}
+
+func (f *PerformanceFlag) Register(ctx context.Context, fs *flag.FlagSet) {
+	f.DatacenterFlag.Register(ctx, fs)
+	f.OutputFlag.Register(ctx, fs)
+
+	fs.IntVar(&f.interval, "i", 0, "Interval ID")
+}
+
+func (f *PerformanceFlag) Process(ctx context.Context) error {
+	if err := f.DatacenterFlag.Process(ctx); err != nil {
+		return err
+	}
+	if err := f.OutputFlag.Process(ctx); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (f *PerformanceFlag) Manager(ctx context.Context) (*performance.Manager, error) {
+	if f.m != nil {
+		return f.m, nil
+	}
+
+	c, err := f.Client()
+	if err != nil {
+		return nil, err
+	}
+
+	f.m = performance.NewManager(c)
+
+	f.m.Sort = true
+
+	return f.m, err
+}
+
+func (f *PerformanceFlag) Interval(val int32) int32 {
+	interval := int32(f.interval)
+
+	if interval == 0 {
+		if val == -1 {
+			// realtime not supported
+			return 300
+		}
+
+		return val
+	}
+
+	return interval
+}
+
+func (f *PerformanceFlag) ErrNotFound(name string) error {
+	return fmt.Errorf("counter %q not found", name)
+}