Add runsc metric-metadata subcommand.

Also group metric-related commands together in their own command group.

PiperOrigin-RevId: 511240778

runsc/cli/main.go

@@ -94,16 +94,19 @@ func Main(version string) {
 	subcommands.Register(new(cmd.Statefile), debugGroup)
 	subcommands.Register(new(cmd.Symbolize), debugGroup)
 	subcommands.Register(new(cmd.Usage), debugGroup)
-	subcommands.Register(new(cmd.MetricExport), debugGroup)
 	subcommands.Register(new(cmd.ReadControl), debugGroup)
 	subcommands.Register(new(cmd.WriteControl), debugGroup)
 
+	const metricGroup = "metrics"
+	subcommands.Register(new(cmd.MetricMetadata), metricGroup)
+	subcommands.Register(new(cmd.MetricExport), metricGroup)
+	subcommands.Register(new(cmd.MetricServer), metricGroup)
+
 	// Internal commands.
 	const internalGroup = "internal use only"
 	subcommands.Register(new(cmd.Boot), internalGroup)
 	subcommands.Register(new(cmd.Gofer), internalGroup)
 	subcommands.Register(new(cmd.Umount), internalGroup)
-	subcommands.Register(new(cmd.MetricServer), internalGroup)
 
 	// Register with the main command line.
 	config.RegisterFlags(flag.CommandLine)

runsc/cmd/BUILD

@@ -22,6 +22,7 @@ go_library(
         "kill.go",
         "list.go",
         "metric_export.go",
+        "metric_metadata.go",
         "metric_server.go",
         "mitigate.go",
         "mitigate_extras.go",
@@ -79,6 +80,7 @@ go_library(
         "@com_github_google_subcommands//:go_default_library",
         "@com_github_opencontainers_runtime_spec//specs-go:go_default_library",
         "@com_github_syndtr_gocapability//capability:go_default_library",
+        "@org_golang_google_protobuf//encoding/prototext:go_default_library",
         "@org_golang_x_sys//unix:go_default_library",
     ],
 )

runsc/cmd/metric_metadata.go

@@ -0,0 +1,62 @@
+// Copyright 2023 The gVisor 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 cmd
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/google/subcommands"
+	"google.golang.org/protobuf/encoding/prototext"
+	"gvisor.dev/gvisor/pkg/metric"
+	"gvisor.dev/gvisor/runsc/cmd/util"
+	"gvisor.dev/gvisor/runsc/flag"
+)
+
+// MetricMetadata implements subcommands.Command for the "metric-metadata" command.
+type MetricMetadata struct {
+}
+
+// Name implements subcommands.Command.Name.
+func (*MetricMetadata) Name() string {
+	return "metric-metadata"
+}
+
+// Synopsis implements subcommands.Command.Synopsis.
+func (*MetricMetadata) Synopsis() string {
+	return "export metric metadata of metrics registered in this build, in text proto format"
+}
+
+// Usage implements subcommands.Command.Usage.
+func (*MetricMetadata) Usage() string {
+	return "metric-metadata"
+}
+
+// SetFlags implements subcommands.Command.SetFlags.
+func (m *MetricMetadata) SetFlags(f *flag.FlagSet) {
+}
+
+// Execute implements subcommands.Command.Execute.
+func (m *MetricMetadata) Execute(ctx context.Context, f *flag.FlagSet, args ...any) subcommands.ExitStatus {
+	if err := metric.Initialize(); err != nil {
+		util.Fatalf("Cannot initialize metrics: %v", err)
+	}
+	registration, err := metric.GetMetricRegistration()
+	if err != nil {
+		util.Fatalf("Cannot get metric registration data: %v", err)
+	}
+	fmt.Println(prototext.MarshalOptions{Multiline: true, EmitASCII: true}.Format(registration))
+	return subcommands.ExitSuccess
+}