Podman System Reset --run-root --graph-root and --user

added options to reinstantiate storage after resetting the podman system using
podman system reset. --run-root and --graph-root define the runRoot and graphRoot to initiate
a new runtime with. --user gets a specified user or uid and generates good approximates for the basic storage
locations of that user. these values, once populated into a new libpd runtime, then are used to create a new storage.conf
file at the proper location (root or rootless default location).

These options allow for a more interactive and useful reset program and ill help eliminate many questions regarding how to configure the basic entities
of container storage.

depends on containers/storage#1096

Signed-off-by: cdoern <cdoern@redhat.com>

cmd/podman/system/reset.go

@@ -1,3 +1,4 @@
+//go:build !remote
 // +build !remote
 
 package system
@@ -6,6 +7,10 @@ import (
 	"bufio"
 	"fmt"
 	"os"
+	"os/exec"
+	"os/user"
+	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/containers/common/pkg/completion"
@@ -14,6 +19,7 @@ import (
 	"github.com/containers/podman/v3/libpod/define"
 	"github.com/containers/podman/v3/pkg/domain/entities"
 	"github.com/containers/podman/v3/pkg/domain/infra"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 )
@@ -34,6 +40,9 @@ var (
 	}
 
 	forceFlag bool
+	givenUser string
+	runDir    string
+	graphDir  string
 )
 
 func init() {
@@ -43,6 +52,15 @@ func init() {
 	})
 	flags := systemResetCommand.Flags()
 	flags.BoolVarP(&forceFlag, "force", "f", false, "Do not prompt for confirmation")
+
+	flags.StringVar(&givenUser, "user", "", "User to setup the DB under")
+	_ = systemResetCommand.RegisterFlagCompletionFunc("user", completion.AutocompleteNone)
+
+	flags.StringVar(&runDir, "run-root", "", "run root directory to use for storage")
+	_ = systemResetCommand.RegisterFlagCompletionFunc("run-root", completion.AutocompleteNone)
+
+	flags.StringVar(&graphDir, "graph-root", "", "graph root directory to use")
+	_ = systemResetCommand.RegisterFlagCompletionFunc("graph-root", completion.AutocompleteNone)
 }
 
 func reset(cmd *cobra.Command, args []string) {
@@ -85,16 +103,123 @@ WARNING! This will remove:
 	registry.ContainerEngine().Shutdown(registry.Context())
 	registry.ImageEngine().Shutdown(registry.Context())
 
+	cfg := registry.PodmanConfig()
+	if len(runDir) > 0 {
+		//cfg.FlagSet.set
+		cfg.Runroot = runDir
+	}
+	if len(graphDir) > 0 {
+		cfg.Engine.StaticDir = graphDir
+	}
+
+	if len(givenUser) > 0 {
+		var u *user.User
+		givenUser = strings.Split(givenUser, ":")[0] // split in case provided with uid:gid
+		_, err := strconv.Atoi(givenUser)
+		if err != nil {
+			u, err = user.Lookup(givenUser)
+			if err != nil {
+				logrus.Error(err)
+			}
+		} else {
+			u, err = user.LookupId(givenUser)
+			if err != nil {
+				logrus.Error(err)
+				os.Exit(define.ExecErrorCodeGeneric)
+			}
+		}
+		uid, err := strconv.Atoi(u.Uid)
+		if err != nil {
+			logrus.Error(err)
+			os.Exit(define.ExecErrorCodeGeneric)
+		}
+
+		home, run, err := GetHomeAndRun(uid)
+		if err != nil {
+			logrus.Error(err)
+			os.Exit(define.ExecErrorCodeGeneric)
+		}
+		if len(runDir) == 0 {
+			_, err = filepath.EvalSymlinks(home)
+			if err != nil {
+				logrus.Error(err)
+				os.Exit(define.ExecErrorCodeGeneric)
+			}
+			if uid != 0 {
+				cfg.Runroot = filepath.Join(run, "containers")
+			}
+		} else {
+			logrus.Error("cannot specify a run-root and a user to generate a run-root from")
+			os.Exit(define.ExecErrorCodeGeneric)
+		}
+		if len(graphDir) == 0 {
+			dataDir := filepath.Join(home, ".local", "share")
+			cfg.Engine.StaticDir = filepath.Join(dataDir, "containers", "storage")
+		} else {
+			logrus.Error("cannot specify a graph-root and a user to generate a graph-root from")
+			os.Exit(define.ExecErrorCodeGeneric)
+		}
+	}
+
 	engine, err := infra.NewSystemEngine(entities.ResetMode, registry.PodmanConfig())
 	if err != nil {
 		logrus.Error(err)
 		os.Exit(define.ExecErrorCodeGeneric)
 	}
 	defer engine.Shutdown(registry.Context())
 
-	if err := engine.Reset(registry.Context()); err != nil {
+	if err := engine.Reset(registry.Context(), (len(runDir) > 0 || len(graphDir) > 0 || len(givenUser) > 0)); err != nil {
 		logrus.Error(err)
 		os.Exit(define.ExecErrorCodeGeneric)
 	}
 	os.Exit(0)
 }
+
+// GetHomeAndRun finds the home and run directories for the given uid, only works with sudo permissions
+func GetHomeAndRun(uid int) (string, string, error) {
+	var home string
+	var run string
+	var out []byte
+	var cmd *exec.Cmd
+	u, err := user.LookupId(fmt.Sprint(uid))
+	if err != nil {
+		return "", "", err
+	}
+	envExec, err := exec.LookPath("env")
+	if err != nil {
+		return "", "", errors.New("cannot find env executable")
+	}
+	machinectl, err := exec.LookPath("machinectl")
+	if err != nil {
+		cmd = exec.Command("su", "-l", u.Username, "--command", envExec)
+	} else {
+		cmd = exec.Command(machinectl, "shell", "-q", u.Username+"@.host", envExec)
+		logrus.Debug("Executing env command machinectl")
+	}
+
+	cmd.Stderr = os.Stderr
+	out, err = cmd.Output()
+	if err != nil {
+		return "", "", err
+	}
+
+	env := strings.Split(string(out), "\n")
+	for _, val := range env {
+		if strings.Contains(val, "XDG_DATA_HOME") || strings.Contains(val, "HOME") {
+			home = strings.Split(val, "=")[1]
+		} else if strings.Contains(val, "XDG_RUNTIME_DIR") {
+			run = strings.Split(val, "=")[1]
+		}
+	}
+	if len(home) == 0 {
+		return "", "", errors.New("called function as root, could not find given user's home directory")
+	}
+	if len(run) == 0 {
+		run = "/run/user/" + string(uid)
+		path := filepath.Join(run, "containers")
+		if err := os.MkdirAll(path, 0700); err != nil {
+			return "", "", errors.Wrapf(err, "unable to make rootless runtime")
+		}
+	}
+	return strings.TrimSpace(home), strings.TrimSpace(run), nil
+}

docs/source/markdown/podman-system-reset.1.md

@@ -26,7 +26,28 @@ Do not prompt for confirmation
 
 Print usage statement
 
+#### **--run-root**
+
+Establishes a new run root directory and storage.conf file once the system is reset, cannot be used in conjunction with --user
+
+#### **--graph-root**
+
+Establishes a new graph root directory and sotrage.conf file once the system is reset, cannot be used in conjunction with --user
+
+#### **--user**
+
+Establishes new run and graph root directories and storage.conf file once the system is reset. the run and graph root directories are generated by retrieving rhe user's home and run directory.
+
 ## EXAMPLES
+Reset the system and create a new storage.conf enerated from the given user's defaults
+```
+$ podman system reset --user=1000:1000
+```
+
+Reset the system and create a new storage.conf with the given run and graph root
+```
+$ podman system reset --run-root=/run/user/1000/containers --graph-root=/home/charliedoern/.local/share/containers
+```
 
 ### Switching rootless user from VFS driver to overlay with fuse-overlayfs
 

libpod/boltdb_state.go

@@ -405,12 +405,29 @@ func (s *BoltState) ValidateDBConfig(runtime *Runtime) error {
 	}
 	defer s.deferredCloseDBCon(db)
 
+	//runRootName := "storage temporary directory (runroot)"
+	//runRootKey := []byte(runRootName)
 	// Check runtime configuration
 	if err := checkRuntimeConfig(db, runtime); err != nil {
+		/*	if runtime.newDB {
+			err = db.Update(func(tx *bolt.Tx) error {
+				rb, err := getRuntimeConfigBucket(tx)
+				if err != nil {
+					return err
+				}
+				dbValue := []byte(runtime.storageConfig.RunRoot)
+				fmt.Println("here", runtime.storageConfig.RunRoot)
+				if err := rb.Put(runRootKey, dbValue); err != nil {
+					return errors.Wrapf(err, "error updating %s in DB runtime config", runRootName)
+				}
+				return nil
+			})
+			return err
+		}*/
 		return err
 	}
 
-	return nil
+	return err
 }
 
 // SetNamespace sets the namespace that will be used for container and pod

libpod/boltdb_state_internal.go

@@ -157,10 +157,10 @@ func checkRuntimeConfig(db *bolt.DB, rt *Runtime) error {
 
 		for _, check := range checks {
 			exists, err := readOnlyValidateConfig(configBkt, check)
-			if err != nil {
+			if err != nil && (err != define.ErrDBBadConfig && !rt.newDB) {
 				return err
 			}
-			if !exists {
+			if !exists || (err != nil && rt.newDB) {
 				missingFields = append(missingFields, check)
 			}
 		}
@@ -187,7 +187,6 @@ func checkRuntimeConfig(db *bolt.DB, rt *Runtime) error {
 			if missing.runtimeValue == "" && missing.defaultValue != "" {
 				dbValue = []byte(missing.defaultValue)
 			}
-
 			if err := configBkt.Put(missing.key, dbValue); err != nil {
 				return errors.Wrapf(err, "error updating %s in DB runtime config", missing.name)
 			}

libpod/options.go

@@ -589,6 +589,16 @@ func WithRuntimeFlags(runtimeFlags []string) RuntimeOption {
 	}
 }
 
+func WithNewDB() RuntimeOption {
+	return func(rt *Runtime) error {
+		if rt.valid {
+			return define.ErrRuntimeFinalized
+		}
+		rt.newDB = true
+		return nil
+	}
+}
+
 // Container Creation Options
 
 // WithMaxLogSize sets the maximum size of container logs.

libpod/reset.go

@@ -17,7 +17,7 @@ import (
 )
 
 // Reset removes all storage
-func (r *Runtime) Reset(ctx context.Context) error {
+func (r *Runtime) Reset(ctx context.Context, removeConf bool) error {
 	var timeout *uint
 	pods, err := r.GetAllPods()
 	if err != nil {
@@ -124,7 +124,20 @@ func (r *Runtime) Reset(ctx context.Context) error {
 	if storageConfPath, err := storage.DefaultConfigFile(rootless.IsRootless()); err == nil {
 		if _, err = os.Stat(storageConfPath); err == nil {
 			fmt.Printf("A storage.conf file exists at %s\n", storageConfPath)
-			fmt.Println("You should remove this file if you did not modify the configuration.")
+			if removeConf {
+				fmt.Println("Removing storage.conf file at", storageConfPath)
+
+				if err = os.Remove(storageConfPath); err != nil {
+					return err
+				}
+				// add here for rootless
+			}
+			confStr := "[storage]\ndriver = \"" + r.store.GraphDriverName() + "\"\nrunroot = \"" + r.store.RunRoot() + "\"\ngraphroot = \"" + r.store.GraphRoot() + "\""
+			newConf := []byte(confStr)
+			if err = os.WriteFile(storageConfPath, newConf, 0644); err != nil {
+				return err
+			}
+			fmt.Println("Wrote new storage config:", r.store, "to", storageConfPath)
 		}
 	} else {
 		if prevError != nil {

libpod/runtime.go

@@ -114,6 +114,8 @@ type Runtime struct {
 	noStore bool
 	// secretsManager manages secrets
 	secretsManager *secrets.SecretsManager
+	// newDB indicates that we do not need to merge the db config, just create a new one
+	newDB bool
 }
 
 // SetXdgDirs ensures the XDG_RUNTIME_DIR env and XDG_CONFIG_HOME variables are set.
@@ -603,7 +605,6 @@ func makeRuntime(ctx context.Context, runtime *Runtime) (retErr error) {
 			return err
 		}
 	}
-
 	// If we need to refresh the state, do it now - things are guaranteed to
 	// be set up by now.
 	if doRefresh {
@@ -618,7 +619,6 @@ func makeRuntime(ctx context.Context, runtime *Runtime) (retErr error) {
 			return err2
 		}
 	}
-
 	// Mark the runtime as valid - ready to be used, cannot be modified
 	// further
 	runtime.valid = true
@@ -628,7 +628,6 @@ func makeRuntime(ctx context.Context, runtime *Runtime) (retErr error) {
 			return err
 		}
 	}
-
 	return nil
 }
 
@@ -981,8 +980,10 @@ func (r *Runtime) configureStore() error {
 	if err != nil {
 		return err
 	}
-
 	r.store = store
+	if store.RunRoot() != r.storageConfig.RunRoot && store.GraphRoot() == r.storageConfig.GraphRoot {
+		logrus.Debug("config reset due to graph root being the default value ")
+	}
 	is.Transport.SetStore(store)
 
 	// Set up a storage service for creating container root filesystems from

pkg/domain/entities/engine_system.go

@@ -9,6 +9,6 @@ import (
 type SystemEngine interface {
 	Renumber(ctx context.Context, flags *pflag.FlagSet, config *PodmanConfig) error
 	Migrate(ctx context.Context, flags *pflag.FlagSet, config *PodmanConfig, options SystemMigrateOptions) error
-	Reset(ctx context.Context) error
+	Reset(ctx context.Context, removeConf bool) error
 	Shutdown(ctx context.Context)
 }

pkg/domain/entities/system.go

@@ -123,3 +123,7 @@ type AuthReport struct {
 	IdentityToken string
 	Status        string
 }
+
+type SetupReport struct {
+	Report []string
+}

pkg/domain/infra/abi/system.go

@@ -326,8 +326,8 @@ func sizeOfPath(path string) (int64, error) {
 	return size, err
 }
 
-func (se *SystemEngine) Reset(ctx context.Context) error {
-	return se.Libpod.Reset(ctx)
+func (se *SystemEngine) Reset(ctx context.Context, removeConf bool) error {
+	return se.Libpod.Reset(ctx, removeConf)
 }
 
 func (se *SystemEngine) Renumber(ctx context.Context, flags *pflag.FlagSet, config *entities.PodmanConfig) error {

pkg/domain/infra/runtime_abi.go

@@ -1,3 +1,4 @@
+//go:build !remote
 // +build !remote
 
 package infra