Files
litestream/cmd/litestream/snapshots.go
2020-12-30 16:10:48 -07:00

118 lines
2.4 KiB
Go

package main
import (
"context"
"errors"
"flag"
"fmt"
"os"
"path/filepath"
"text/tabwriter"
"time"
"github.com/benbjohnson/litestream"
)
type SnapshotsCommand struct{}
func (c *SnapshotsCommand) Run(ctx context.Context, args []string) (err error) {
var configPath string
fs := flag.NewFlagSet("litestream-snapshots", flag.ContinueOnError)
registerConfigFlag(fs, &configPath)
replicaName := fs.String("replica", "", "replica name")
fs.Usage = c.Usage
if err := fs.Parse(args); err != nil {
return err
} else if fs.NArg() == 0 || fs.Arg(0) == "" {
return fmt.Errorf("database path required")
} else if fs.NArg() > 1 {
return fmt.Errorf("too many arguments")
}
// Load configuration.
if configPath == "" {
return errors.New("-config required")
}
config, err := ReadConfigFile(configPath)
if err != nil {
return err
}
// Determine absolute path for database.
dbPath, err := filepath.Abs(fs.Arg(0))
if err != nil {
return err
}
// Instantiate DB.
dbConfig := config.DBConfig(dbPath)
if dbConfig == nil {
return fmt.Errorf("database not found in config: %s", dbPath)
}
db, err := newDBFromConfig(dbConfig)
if err != nil {
return err
}
// Find snapshots by db or replica.
var infos []*litestream.SnapshotInfo
if *replicaName != "" {
if r := db.Replica(*replicaName); r == nil {
return fmt.Errorf("replica %q not found for database %q", *replicaName, dbPath)
} else if infos, err = r.Snapshots(ctx); err != nil {
return err
}
} else {
if infos, err = db.Snapshots(ctx); err != nil {
return err
}
}
// List all snapshots.
w := tabwriter.NewWriter(os.Stdout, 0, 8, 1, '\t', 0)
fmt.Fprintln(w, "replica\tgeneration\tindex\tsize\tcreated")
for _, info := range infos {
fmt.Fprintf(w, "%s\t%s\t%d\t%d\t%s\n",
info.Replica,
info.Generation,
info.Index,
info.Size,
info.CreatedAt.Format(time.RFC3339),
)
}
w.Flush()
return nil
}
func (c *SnapshotsCommand) Usage() {
fmt.Printf(`
The snapshots command lists all snapshots available for a database.
Usage:
litestream snapshots [arguments] DB
Arguments:
-config PATH
Specifies the configuration file.
Defaults to %s
-replica NAME
Optional, filter by a specific replica.
Examples:
# List all snapshots for a database.
$ litestream snapshots /path/to/db
# List all snapshots on S3.
$ litestream snapshots -replica s3 /path/to/db
`[1:],
DefaultConfigPath,
)
}