Add a Cobra root command.

cmd/root.go

@@ -0,0 +1,46 @@
+// Copyright 2024 Google 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 cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "gcsfuse [flags] bucket mount_point",
+	Short: "Mount a specified GCS bucket or all accessible buckets locally",
+	Long: `Cloud Storage FUSE is an open source FUSE adapter that lets you mount
+          and access Cloud Storage buckets as local file systems. For a
+          technical overview of Cloud Storage FUSE, see
+          https://cloud.google.com/storage/docs/gcs-fuse.`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		// TODO: the following error will be removed once the command is implemented.
+		return fmt.Errorf("unsupported operation")
+	},
+}
+
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
+}
+
+func init() {
+	// TODO: add flags and bind them with viper here.
+}

go.mod

@@ -19,6 +19,7 @@ require (
 	github.com/jacobsa/syncutil v0.0.0-20180201203307-228ac8e5a6c3
 	github.com/jacobsa/timeutil v0.0.0-20170205232429-577e5acbbcf6
 	github.com/kardianos/osext v0.0.0-20190222173326-2bc1f35cddc0
+	github.com/spf13/cobra v1.1.3
 	github.com/stretchr/testify v1.9.0
 	github.com/urfave/cli v1.22.15
 	go.opencensus.io v0.24.0
@@ -62,12 +63,14 @@ require (
 	github.com/gorilla/handlers v1.5.2 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.15.2 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/pkg/xattr v0.4.9 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/prometheus/prometheus v0.35.0 // indirect
 	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.51.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.51.0 // indirect
 	go.opentelemetry.io/otel v1.26.0 // indirect

go.sum

@@ -712,6 +712,7 @@ github.com/imdario/mergo v0.3.8/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJ
 github.com/imdario/mergo v0.3.10/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/imdario/mergo v0.3.11/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
+github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/intel/goresctrl v0.2.0/go.mod h1:+CZdzouYFn5EsxgqAQTEzMfwKwuc0fVdMrT9FCCAVRQ=
 github.com/j-keck/arping v0.0.0-20160618110441-2cf9dc699c56/go.mod h1:ymszkNOg6tORTn+6F6j+Jc8TOr5osrynvN6ivFWZ2GA=
@@ -1046,12 +1047,14 @@ github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkU
 github.com/spf13/cobra v0.0.2-0.20171109065643-2da4a54c5cee/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v1.0.0/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
+github.com/spf13/cobra v1.1.3 h1:xghbfqPkxzxP3C/f3n5DdpAbdKLj4ZE4BWQI362l53M=
 github.com/spf13/cobra v1.1.3/go.mod h1:pGADOWyqRD/YMrPZigI/zbliZ2wVD/23d+is3pSWzOo=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.1-0.20171106142849-4c012f6dcd95/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.1/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
+github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/yZzE=
 github.com/spf13/viper v1.7.0/go.mod h1:8WkrPz2fc9jxqZNCJI/76HCieCp4Q8HaLFoCha5qpdg=

main.go

@@ -27,6 +27,7 @@ import (
 	"path"
 	"strings"
 
+	"github.com/googlecloudplatform/gcsfuse/v2/cmd"
 	"github.com/googlecloudplatform/gcsfuse/v2/internal/canned"
 	"github.com/googlecloudplatform/gcsfuse/v2/internal/config"
 	"github.com/googlecloudplatform/gcsfuse/v2/internal/locker"
@@ -442,6 +443,10 @@ func handlePanicWhileMounting() {
 }
 
 func main() {
+	if strings.ToLower(os.Getenv("ENABLE_GCSFUSE_VIPER_CONFIG")) == "true" {
+		cmd.Execute()
+		return
+	}
 	defer handlePanicWhileMounting()
 
 	// Make logging output better.