Cloudfuse service linux cmd

cmd/service_linux.go

@@ -0,0 +1,273 @@
+//go:build linux
+
+/*
+   Licensed under the MIT License <http://opensource.org/licenses/MIT>.
+
+   Copyright © 2023-2024 Seagate Technology LLC and/or its Affiliates
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal
+   in the Software without restriction, including without limitation the rights
+   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+   copies of the Software, and to permit persons to whom the Software is
+   furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in all
+   copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+*/
+
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"html/template"
+	"io/fs"
+	"os"
+	"os/exec"
+	"os/user"
+	"path/filepath"
+	"strings"
+
+	"github.com/Seagate/cloudfuse/common"
+	"github.com/spf13/cobra"
+)
+
+type serviceOptions struct {
+	ConfigFile  string
+	MountPath   string
+	ServiceUser string
+}
+
+// Section defining all the command that we have in secure feature
+var serviceCmd = &cobra.Command{
+	Use:               "service",
+	Short:             "Manage cloudfuse startup process on Linux",
+	Long:              "Manage cloudfuse startup process on Linux",
+	SuggestFor:        []string{"ser", "serv"},
+	Example:           "cloudfuse service install",
+	FlagErrorHandling: cobra.ExitOnError,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return errors.New("missing command options\n\nDid you mean this?\n\tcloudfuse service install\n\nRun 'cloudfuse service --help' for usage")
+	},
+}
+
+var mountPath string
+var configPath string
+var serviceUser string
+
+var installCmd = &cobra.Command{
+	Use:               "install",
+	Short:             "Installs a service file for a single mount with Cloudfuse. Requires elevated permissions.",
+	Long:              "Installs a service file for a single mount with Cloudfuse. Requires elevated permissions.",
+	SuggestFor:        []string{"ins", "inst"},
+	Example:           "cloudfuse service install --mount-path=<path/to/mount/point> --config-file=<path/to/config/file> --user=<username>",
+	FlagErrorHandling: cobra.ExitOnError,
+	RunE: func(cmd *cobra.Command, args []string) error {
+
+		var err error
+		mountPath, err = getAbsPath(mountPath)
+		if err != nil {
+			return err
+		}
+		configPath, err = getAbsPath(configPath)
+		if err != nil {
+			return err
+		}
+
+		mountExists := common.DirectoryExists(mountPath)
+		if !mountExists {
+			return fmt.Errorf("the mount path provided does not exist")
+			// TODO: add useage output upon failure with input
+		}
+		// TODO: consider logging a warning if the mount path is empty
+
+		_, err = os.Stat(configPath)
+		if errors.Is(err, fs.ErrNotExist) {
+			return fmt.Errorf("error, the configfile path provided does not exist")
+		}
+
+		//create the new user and set permissions
+		err = setUser(serviceUser, mountPath, configPath)
+		if err != nil {
+			fmt.Println("Error setting permissions for user:", err)
+			return err
+		}
+
+		serviceFile, err := newServiceFile(mountPath, configPath, serviceUser)
+		if err != nil {
+			return fmt.Errorf("error when attempting to create service file: [%s]", err.Error())
+		}
+
+		// run systemctl daemon-reload
+		systemctlDaemonReloadCmd := exec.Command("systemctl", "daemon-reload")
+		err = systemctlDaemonReloadCmd.Run()
+		if err != nil {
+			return fmt.Errorf("failed to run 'systemctl daemon-reload' command due to following error: [%s]", err.Error())
+		}
+
+		// Enable the service to start at system boot
+		systemctlEnableCmd := exec.Command("systemctl", "enable", serviceFile)
+		err = systemctlEnableCmd.Run()
+		if err != nil {
+			return fmt.Errorf("failed to run 'systemctl daemon-reload' command due to following error: [%s]", err.Error())
+		}
+		return nil
+	},
+}
+
+var serviceName string
+var uninstallCmd = &cobra.Command{
+	Use:               "uninstall",
+	Short:             "Uninstall a startup process for Cloudfuse.",
+	Long:              "Uninstall a startup process for Cloudfuse.",
+	SuggestFor:        []string{"uninst", "uninstal"},
+	Example:           "cloudfuse service uninstall --mount-path=<path/to/mount/path>",
+	FlagErrorHandling: cobra.ExitOnError,
+	RunE: func(cmd *cobra.Command, args []string) error {
+
+		// get absolute path of provided relative mount path
+		var err error
+		mountPath, err = getAbsPath(serviceName)
+		if err != nil {
+			return err
+		}
+
+		folderList := strings.Split(mountPath, "/")
+		serviceFile := "cloudfuse-" + folderList[len(folderList)-1] + ".service"
+		serviceFilePath := "/etc/systemd/system/" + serviceFile
+		if _, err := os.Stat(serviceFilePath); err == nil {
+			removeFileCmd := exec.Command("rm", serviceFilePath)
+			err := removeFileCmd.Run()
+			if err != nil {
+				return fmt.Errorf("failed to delete "+serviceName+" file from /etc/systemd/system due to following error: [%s]", err.Error())
+			}
+		} else if os.IsNotExist(err) {
+			return fmt.Errorf("failed to delete "+serviceName+" file from /etc/systemd/system due to following error: [%s]", err.Error())
+		}
+
+		// reload daemon
+		systemctlDaemonReloadCmd := exec.Command("systemctl", "daemon-reload")
+		err = systemctlDaemonReloadCmd.Run()
+		if err != nil {
+			return fmt.Errorf("failed to run 'systemctl daemon-reload' command due to following error: [%s]", err.Error())
+		}
+		return nil
+	},
+}
+
+//--------------- command section ends
+
+func newServiceFile(mountPath string, configPath string, serviceUser string) (string, error) {
+	serviceTemplate := `
+[Unit]
+Description=Cloudfuse is an open source project developed to provide a virtual filesystem backed by S3 or Azure storage.
+After=network-online.target
+Requires=network-online.target
+
+[Service]
+# User service will run as.
+User={{.ServiceUser}}
+
+# Under the hood
+Type=forking
+ExecStart=/usr/bin/cloudfuse mount {{.MountPath}} --config-file={{.ConfigFile}} -o allow_other
+ExecStop=/usr/bin/fusermount -u {{.MountPath}} -z
+
+[Install]
+WantedBy=multi-user.target
+`
+
+	config := serviceOptions{
+		ConfigFile:  configPath,
+		MountPath:   mountPath,
+		ServiceUser: serviceUser,
+	}
+
+	tmpl, err := template.New("service").Parse(serviceTemplate)
+	if err != nil {
+		return "", fmt.Errorf("error creating new service file: [%s]", err.Error())
+	}
+
+	folderList := strings.Split(mountPath, "/")
+	serviceName := "cloudfuse-" + folderList[len(folderList)-1] + ".service"
+	servicePath := "/etc/systemd/system/" + serviceName
+
+	var newFile *os.File
+	if _, err = os.Stat(servicePath); os.IsNotExist(err) {
+		newFile, err = os.Create(servicePath)
+		if err != nil {
+			return "", fmt.Errorf("error creating new service file: [%s]", err.Error())
+		}
+	} else {
+		delServFileCmd := exec.Command("rm", servicePath)
+		err = delServFileCmd.Run()
+		if err != nil {
+			return "", fmt.Errorf("failed to replace the service file due to the following error: [%s]", err.Error())
+		}
+		newFile, err = os.Create(servicePath)
+		if err != nil {
+			return "", fmt.Errorf("error creating new service file: [%s]", err.Error())
+		}
+	}
+
+	err = tmpl.Execute(newFile, config)
+	if err != nil {
+		return "", fmt.Errorf("error creating new service file: [%s]", err.Error())
+	}
+
+	return serviceName, nil
+}
+
+func setUser(serviceUser string, mountPath string, configPath string) error {
+	_, err := user.Lookup(serviceUser)
+	if err != nil {
+		if strings.Contains(err.Error(), "unknown user") {
+			// create the user
+			userAddCmd := exec.Command("useradd", "-m", serviceUser)
+			err = userAddCmd.Run()
+			if err != nil {
+				return fmt.Errorf("failed to create user due to following error: [%s]", err.Error())
+			}
+			fmt.Println("user " + serviceUser + " has been created")
+		}
+	}
+	// advise on required permissions
+	fmt.Println("ensure the user, " + serviceUser + ", has the following access: \n" + mountPath + ": read, write, and execute \n" + configPath + ": read \n")
+
+	return nil
+}
+
+// takes a file or folder name and returns its absolute path
+func getAbsPath(leaf string) (string, error) {
+	var absPath string
+	var err error
+	if !filepath.IsAbs(leaf) {
+		absPath, err = filepath.Abs(leaf)
+		if err != nil {
+			return "", fmt.Errorf("couldn't format the path string", err.Error())
+		}
+	}
+	return absPath, err
+}
+
+func init() {
+	rootCmd.AddCommand(serviceCmd)
+	rootCmd.SilenceUsage = false
+	serviceCmd.AddCommand(installCmd)
+	installCmd.Flags().StringVar(&mountPath, "mount-path", "", "Input mount path")
+	installCmd.Flags().StringVar(&configPath, "config-file", "", "Input config file")
+	installCmd.Flags().StringVar(&serviceUser, "user", "cloudfuse", "Input service user")
+	installCmd.MarkFlagRequired("mount-path")
+	installCmd.MarkFlagRequired("config-file")
+	serviceCmd.AddCommand(uninstallCmd)
+	uninstallCmd.Flags().StringVar(&serviceName, "mount-path", "", "Input mount path")
+	uninstallCmd.MarkFlagRequired("mount-path")
+}