feat: add backup path (#10649)

## Description
Closes:  #10533

Cosmovisor can cause problems related to disk space when they try backing up, not enough space might fail the node.
A new feature is added to allow user to set a backup path, which can be separated from the node-home directory.
A new env var `DAEMON_BACKUP_DIR` is added. If `DAEMON_BACKUP_DIR` is set, backups will go there instead of `DAEMON_HOME`. 

- [x] add custom data backup dir 
- [x] add tests



---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [x] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

cosmovisor/CHANGELOG.md

@@ -39,7 +39,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Features
 
 + [\#10285](https://github.com/cosmos/cosmos-sdk/pull/10316) Added `run` action.
-
++ [\#10533](https://github.com/cosmos/cosmos-sdk/pull/10649) Added environmental variable `DAEMON_BACKUP_DIR` to allow node to set a custom backup directory.
 ### Deprecated
 
 + [\#10285](https://github.com/cosmos/cosmos-sdk/pull/10316) Running `cosmovisor` without the `run` argument.

cosmovisor/args.go

@@ -25,15 +25,16 @@ const (
 	EnvDownloadBin          = "DAEMON_ALLOW_DOWNLOAD_BINARIES"
 	EnvRestartUpgrade       = "DAEMON_RESTART_AFTER_UPGRADE"
 	EnvSkipBackup           = "UNSAFE_SKIP_BACKUP"
+	EnvDataBackupPath       = "DAEMON_DATA_BACKUP_DIR"
 	EnvInterval             = "DAEMON_POLL_INTERVAL"
 	EnvPreupgradeMaxRetries = "DAEMON_PREUPGRADE_MAX_RETRIES"
 )
 
 const (
-	rootName        = "cosmovisor"
-	genesisDir      = "genesis"
-	upgradesDir     = "upgrades"
-	currentLink     = "current"
+	rootName    = "cosmovisor"
+	genesisDir  = "genesis"
+	upgradesDir = "upgrades"
+	currentLink = "current"
 )
 
 // must be the same as x/upgrade/types.UpgradeInfoFilename
@@ -47,6 +48,7 @@ type Config struct {
 	RestartAfterUpgrade   bool
 	PollInterval          time.Duration
 	UnsafeSkipBackup      bool
+	DataBackupPath        string
 	PreupgradeMaxRetries  int
 
 	// currently running upgrade
@@ -129,8 +131,13 @@ func (cfg *Config) CurrentBin() (string, error) {
 func GetConfigFromEnv() (*Config, error) {
 	var errs []error
 	cfg := &Config{
-		Home: os.Getenv(EnvHome),
-		Name: os.Getenv(EnvName),
+		Home:           os.Getenv(EnvHome),
+		Name:           os.Getenv(EnvName),
+		DataBackupPath: os.Getenv(EnvDataBackupPath),
+	}
+
+	if cfg.DataBackupPath == "" {
+		cfg.DataBackupPath = cfg.Home
 	}
 
 	var err error
@@ -213,6 +220,25 @@ func (cfg *Config) validate() []error {
 		}
 	}
 
+	// check the DataBackupPath
+	if cfg.UnsafeSkipBackup == true {
+		return errs
+	}
+	// if UnsafeSkipBackup is false, check if the DataBackupPath valid
+	switch {
+	case cfg.DataBackupPath == "":
+		errs = append(errs, errors.New(EnvDataBackupPath + " must not be empty"))
+	case !filepath.IsAbs(cfg.DataBackupPath):
+		errs = append(errs, errors.New(cfg.DataBackupPath + " must be an absolute path"))
+	default:
+		switch info, err := os.Stat(cfg.DataBackupPath); {
+		case err != nil:
+			errs = append(errs, fmt.Errorf("%q must be a valid directory: %w", cfg.DataBackupPath, err))
+		case !info.IsDir():
+			errs = append(errs, fmt.Errorf("%q must be a valid directory", cfg.DataBackupPath))
+		}
+	}
+
 	return errs
 }
 
@@ -305,13 +331,15 @@ func (cfg Config) DetailString() string {
 		{EnvRestartUpgrade, fmt.Sprintf("%t", cfg.RestartAfterUpgrade)},
 		{EnvInterval, fmt.Sprintf("%s", cfg.PollInterval)},
 		{EnvSkipBackup, fmt.Sprintf("%t", cfg.UnsafeSkipBackup)},
+		{EnvDataBackupPath, cfg.DataBackupPath},
 		{EnvPreupgradeMaxRetries, fmt.Sprintf("%d", cfg.PreupgradeMaxRetries)},
 	}
 	derivedEntries := []struct{ name, value string }{
 		{"Root Dir", cfg.Root()},
 		{"Upgrade Dir", cfg.BaseUpgradeDir()},
 		{"Genesis Bin", cfg.GenesisBin()},
 		{"Monitored File", cfg.UpgradeInfoFilePath()},
+		{"Data Backup Dir", cfg.DataBackupPath},
 	}
 
 	var sb strings.Builder