feat(GODT-2814): Standalone Server Manager

Convert ServerManger into a standalone service so that it can become a
self contained module.

internal/files/files.go

@@ -0,0 +1,134 @@
+// Copyright (c) 2023 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package files
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+func MoveDir(from, to string) error {
+	entries, err := os.ReadDir(from)
+	if err != nil {
+		return err
+	}
+
+	for _, entry := range entries {
+		if entry.IsDir() {
+			if err := os.Mkdir(filepath.Join(to, entry.Name()), 0o700); err != nil {
+				return err
+			}
+
+			if err := MoveDir(filepath.Join(from, entry.Name()), filepath.Join(to, entry.Name())); err != nil {
+				return err
+			}
+
+			if err := os.RemoveAll(filepath.Join(from, entry.Name())); err != nil {
+				return err
+			}
+		} else {
+			if err := moveFile(filepath.Join(from, entry.Name()), filepath.Join(to, entry.Name())); err != nil {
+				return err
+			}
+		}
+	}
+
+	return os.Remove(from)
+}
+
+func moveFile(from, to string) error {
+	if err := os.MkdirAll(filepath.Dir(to), 0o700); err != nil {
+		return err
+	}
+
+	return os.Rename(from, to)
+}
+
+func CopyDir(from, to string) error {
+	entries, err := os.ReadDir(from)
+	if err != nil {
+		return err
+	}
+	if err := CreateIfNotExists(to, 0o700); err != nil {
+		return err
+	}
+	for _, entry := range entries {
+		sourcePath := filepath.Join(from, entry.Name())
+		destPath := filepath.Join(to, entry.Name())
+
+		if entry.IsDir() {
+			if err := CopyDir(sourcePath, destPath); err != nil {
+				return err
+			}
+		} else {
+			if err := CopyFile(sourcePath, destPath); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func CopyFile(srcFile, dstFile string) error {
+	out, err := os.Create(filepath.Clean(dstFile))
+	defer func(out *os.File) {
+		_ = out.Close()
+	}(out)
+
+	if err != nil {
+		return err
+	}
+
+	in, err := os.Open(filepath.Clean(srcFile))
+	defer func(in *os.File) {
+		_ = in.Close()
+	}(in)
+
+	if err != nil {
+		return err
+	}
+
+	_, err = io.Copy(out, in)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func Exists(filePath string) bool {
+	if _, err := os.Stat(filePath); os.IsNotExist(err) {
+		return false
+	}
+
+	return true
+}
+
+func CreateIfNotExists(dir string, perm os.FileMode) error {
+	if Exists(dir) {
+		return nil
+	}
+
+	if err := os.MkdirAll(dir, perm); err != nil {
+		return fmt.Errorf("failed to create directory: '%s', error: '%s'", dir, err.Error())
+	}
+
+	return nil
+}