feat(cmd/migrate_mysql_database): Add slu migrate-mysql-database command

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Gj7u6kyvegVdGpXfCfFvBZ

Author: ondrejsika

cmd/cmd.go

@@ -42,6 +42,7 @@ import (
 	_ "github.com/sikalabs/slr/cmd/list_mimio_s3_bucket"
 	_ "github.com/sikalabs/slr/cmd/list_mimio_s3_buckets"
 	_ "github.com/sikalabs/slr/cmd/memory_usage"
+	_ "github.com/sikalabs/slr/cmd/migrate_mysql_database"
 	_ "github.com/sikalabs/slr/cmd/next_dev_docker_tag"
 	_ "github.com/sikalabs/slr/cmd/nothing"
 	_ "github.com/sikalabs/slr/cmd/ondrejsika"

cmd/migrate_mysql_database/migrate_mysql_database.go

@@ -0,0 +1,142 @@
+package migrate_mysql_database
+
+import (
+	"fmt"
+	"net/url"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/sikalabs/slr/cmd/root"
+	"github.com/spf13/cobra"
+)
+
+var (
+	FlagSource string
+	FlagTarget string
+)
+
+func init() {
+	root.Cmd.AddCommand(Cmd)
+	Cmd.Flags().StringVar(&FlagSource, "source", "", "Source MySQL URL, e.g. mysql://user:pass@host:port/database (required)")
+	Cmd.Flags().StringVar(&FlagTarget, "target", "", "Target MySQL URL, e.g. mysql://user:pass@host:port/database (required)")
+	Cmd.MarkFlagRequired("source")
+	Cmd.MarkFlagRequired("target")
+}
+
+var Cmd = &cobra.Command{
+	Use:   "migrate-mysql-database",
+	Short: "Migrate a MySQL database from a source to a target server",
+	Long: `Migrate a MySQL database from a source server/database to a target server/database.
+
+It streams the output of "mysqldump" for the source database directly into
+"mysql" for the target database, so both the "mysqldump" and "mysql" binaries
+must be available on PATH.`,
+	Args: cobra.NoArgs,
+	Run: func(c *cobra.Command, args []string) {
+		if err := migrate(FlagSource, FlagTarget); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+			os.Exit(1)
+		}
+	},
+}
+
+type mysqlConn struct {
+	Host     string
+	Port     string
+	User     string
+	Password string
+	Database string
+}
+
+func parseMySQLURL(raw string) (*mysqlConn, error) {
+	u, err := url.Parse(raw)
+	if err != nil {
+		return nil, fmt.Errorf("invalid MySQL URL: %w", err)
+	}
+	if u.Scheme != "mysql" {
+		return nil, fmt.Errorf("invalid MySQL URL scheme %q, expected \"mysql\"", u.Scheme)
+	}
+	database := strings.TrimPrefix(u.Path, "/")
+	if database == "" {
+		return nil, fmt.Errorf("MySQL URL must include a database name, e.g. mysql://user:pass@host:port/database")
+	}
+	host := u.Hostname()
+	if host == "" {
+		return nil, fmt.Errorf("MySQL URL must include a host")
+	}
+	port := u.Port()
+	if port == "" {
+		port = "3306"
+	}
+	password, _ := u.User.Password()
+	return &mysqlConn{
+		Host:     host,
+		Port:     port,
+		User:     u.User.Username(),
+		Password: password,
+		Database: database,
+	}, nil
+}
+
+func migrate(sourceURL, targetURL string) error {
+	source, err := parseMySQLURL(sourceURL)
+	if err != nil {
+		return fmt.Errorf("source: %w", err)
+	}
+	target, err := parseMySQLURL(targetURL)
+	if err != nil {
+		return fmt.Errorf("target: %w", err)
+	}
+
+	if _, err := exec.LookPath("mysqldump"); err != nil {
+		return fmt.Errorf("mysqldump binary not found in PATH: %w", err)
+	}
+	if _, err := exec.LookPath("mysql"); err != nil {
+		return fmt.Errorf("mysql binary not found in PATH: %w", err)
+	}
+
+	fmt.Printf("Migrating database %q from %s:%s to %q on %s:%s...\n",
+		source.Database, source.Host, source.Port, target.Database, target.Host, target.Port)
+
+	dumpCmd := exec.Command("mysqldump",
+		"-h", source.Host,
+		"-P", source.Port,
+		"-u", source.User,
+		"--single-transaction",
+		"--routines",
+		"--triggers",
+		source.Database,
+	)
+	dumpCmd.Env = append(os.Environ(), "MYSQL_PWD="+source.Password)
+	dumpCmd.Stderr = os.Stderr
+
+	restoreCmd := exec.Command("mysql",
+		"-h", target.Host,
+		"-P", target.Port,
+		"-u", target.User,
+		target.Database,
+	)
+	restoreCmd.Env = append(os.Environ(), "MYSQL_PWD="+target.Password)
+	restoreCmd.Stderr = os.Stderr
+	restoreCmd.Stdout = os.Stdout
+
+	pipe, err := dumpCmd.StdoutPipe()
+	if err != nil {
+		return fmt.Errorf("failed to create pipe between mysqldump and mysql: %w", err)
+	}
+	restoreCmd.Stdin = pipe
+
+	if err := restoreCmd.Start(); err != nil {
+		return fmt.Errorf("failed to start mysql: %w", err)
+	}
+	if err := dumpCmd.Run(); err != nil {
+		return fmt.Errorf("mysqldump failed: %w", err)
+	}
+	if err := restoreCmd.Wait(); err != nil {
+		return fmt.Errorf("mysql restore failed: %w", err)
+	}
+
+	fmt.Println("Migration completed successfully!")
+	return nil
+}