create corrosion config

internal/machine/corrosion/config.go

@@ -0,0 +1,104 @@
+package corrosion
+
+import (
+	"fmt"
+	"github.com/BurntSushi/toml"
+	"net/netip"
+	"os"
+	"os/user"
+	"path/filepath"
+	"strconv"
+)
+
+const (
+	DefaultUser       = "uncloud"
+	DefaultGossipPort = 51001
+	DefaultAPIPort    = 51002
+)
+
+// Config represents the Corrosion config.
+type Config struct {
+	DB     DBConfig     `toml:"db"`
+	Gossip GossipConfig `toml:"gossip"`
+	API    APIConfig    `toml:"api"`
+	Admin  AdminConfig  `toml:"admin"`
+}
+
+type DBConfig struct {
+	Path        string   `toml:"path"`
+	SchemaPaths []string `toml:"schema_paths"`
+}
+
+type GossipConfig struct {
+	Addr      netip.AddrPort `toml:"addr"`
+	Plaintext bool           `toml:"plaintext"`
+}
+
+type APIConfig struct {
+	Addr netip.AddrPort `toml:"addr"`
+}
+
+type AdminConfig struct {
+	Path string `toml:"path"`
+}
+
+func (c *Config) Write(path, owner string) error {
+	data, err := toml.Marshal(c)
+	if err != nil {
+		return fmt.Errorf("marshal config: %w", err)
+	}
+
+	if err := os.WriteFile(path, data, 0600); err != nil {
+		return err
+	}
+	if owner != "" {
+		usr, err := user.Lookup(owner)
+		if err != nil {
+			return fmt.Errorf("lookup user %q: %w", owner, err)
+		}
+		uid, err := strconv.Atoi(usr.Uid)
+		if err != nil {
+			return fmt.Errorf("parse %q user ID (UID) %q: %w", owner, usr.Uid, err)
+		}
+		gid, err := strconv.Atoi(usr.Gid)
+		if err != nil {
+			return fmt.Errorf("parse %q user group ID (GID) %q: %w", owner, usr.Gid, err)
+		}
+		if err = os.Chown(path, uid, gid); err != nil {
+			return fmt.Errorf("chown %q: %w", path, err)
+		}
+	}
+	return nil
+}
+
+func MkDataDir(dir, owner string) error {
+	parent, _ := filepath.Split(dir)
+	// Use 0711 for parent directories to allow `owner` to access its nested data directory.
+	if err := os.MkdirAll(parent, 0711); err != nil {
+		return fmt.Errorf("create directory %q: %w", parent, err)
+	}
+	if err := os.Mkdir(dir, 0700); err != nil {
+		if !os.IsExist(err) {
+			return fmt.Errorf("create directory %q: %w", dir, err)
+		}
+	}
+
+	if owner != "" {
+		usr, err := user.Lookup(owner)
+		if err != nil {
+			return fmt.Errorf("lookup user %q: %w", owner, err)
+		}
+		uid, err := strconv.Atoi(usr.Uid)
+		if err != nil {
+			return fmt.Errorf("parse %q user ID (UID) %q: %w", owner, usr.Uid, err)
+		}
+		gid, err := strconv.Atoi(usr.Gid)
+		if err != nil {
+			return fmt.Errorf("parse %q user group ID (GID) %q: %w", owner, usr.Gid, err)
+		}
+		if err = os.Chown(dir, uid, gid); err != nil {
+			return fmt.Errorf("chown %q: %w", dir, err)
+		}
+	}
+	return nil
+}

internal/machine/corrosion/service.go

@@ -0,0 +1,5 @@
+package corrosion
+
+type Service interface {
+	Start() error
+}

internal/machine/corrosion/systemd.go

@@ -0,0 +1,36 @@
+package corrosion
+
+import (
+	"fmt"
+	"log/slog"
+	"os/exec"
+)
+
+const DefaultSystemdUnit = "uncloud-corrosion.service"
+
+type SystemdService struct {
+	DataDir string
+	Unit    string
+	User    string
+}
+
+func DefaultSystemdService(dataDir string) *SystemdService {
+	return &SystemdService{
+		DataDir: dataDir,
+		Unit:    DefaultSystemdUnit,
+		User:    DefaultUser,
+	}
+}
+
+func (s *SystemdService) Configure() error {
+	// TODO: create config.toml and schema dir in DataDir.
+	return nil
+}
+
+func (s *SystemdService) Start() error {
+	if _, err := exec.Command("systemctl", "start", s.Unit).Output(); err != nil {
+		return fmt.Errorf("systemctl start %s: %w", s.Unit, err)
+	}
+	slog.Info("Corrosion systemd service started.", "unit", s.Unit)
+	return nil
+}