Files
lazyssh/internal/adapters/data/ssh_config_file/config_io.go
T

127 lines
3.9 KiB
Go

// Copyright 2025.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package ssh_config_file
import (
"fmt"
"os"
"path/filepath"
"time"
"github.com/kevinburke/ssh_config"
)
// loadConfig reads and parses the SSH config file.
// If the file does not exist, it returns an empty config without error to support first-run behavior.
func (r *Repository) loadConfig() (*ssh_config.Config, error) {
file, err := r.fileSystem.Open(r.configPath)
if err != nil {
if r.fileSystem.IsNotExist(err) {
return &ssh_config.Config{Hosts: []*ssh_config.Host{}}, nil
}
return nil, fmt.Errorf("failed to open config file: %w", err)
}
defer func() {
if cerr := file.Close(); cerr != nil {
r.logger.Warnf("failed to close config file: %v", cerr)
}
}()
cfg, err := ssh_config.Decode(file)
if err != nil {
return nil, fmt.Errorf("failed to decode config: %w", err)
}
return cfg, nil
}
// saveConfig writes the SSH config back to the file with atomic operations and backup management.
func (r *Repository) saveConfig(cfg *ssh_config.Config) error {
configDir := filepath.Dir(r.configPath)
tempFile, err := r.createTempFile(configDir)
if err != nil {
return fmt.Errorf("failed to create temporary file: %w", err)
}
defer func() {
if removeErr := r.fileSystem.Remove(tempFile); removeErr != nil {
r.logger.Warnf("failed to remove temporary file %s: %v", tempFile, removeErr)
}
}()
if err := r.writeConfigToFile(tempFile, cfg); err != nil {
return fmt.Errorf("failed to write config to temporary file: %w", err)
}
// Ensure a one-time original backup exists before any modifications managed by lazyssh.
if err := r.createOriginalBackupIfNeeded(); err != nil {
return fmt.Errorf("failed to create original backup: %w", err)
}
if err := r.createBackup(); err != nil {
return fmt.Errorf("failed to create backup: %w", err)
}
if err := r.fileSystem.Rename(tempFile, r.configPath); err != nil {
return fmt.Errorf("failed to atomically replace config file: %w", err)
}
r.logger.Infof("SSH config successfully updated: %s", r.configPath)
return nil
}
// writeConfigToFile writes the SSH config content to the specified file
func (r *Repository) writeConfigToFile(filePath string, cfg *ssh_config.Config) error {
file, err := r.fileSystem.OpenFile(filePath, os.O_WRONLY|os.O_TRUNC, SSHConfigPerms)
if err != nil {
return fmt.Errorf("failed to open file for writing: %w", err)
}
defer func() {
if cerr := file.Close(); cerr != nil {
r.logger.Warnf("failed to close file %s: %v", filePath, cerr)
}
}()
configContent := cfg.String()
if _, err := file.WriteString(configContent); err != nil {
return fmt.Errorf("failed to write config content: %w", err)
}
if err := file.Sync(); err != nil {
return fmt.Errorf("failed to sync file to disk: %w", err)
}
return nil
}
// createTempFile creates a temporary file in the specified directory
func (r *Repository) createTempFile(dir string) (string, error) {
timestamp := time.Now().Format("20060102150405")
tempFileName := fmt.Sprintf("config%s%s", timestamp, TempSuffix)
tempFilePath := filepath.Join(dir, tempFileName)
// Create the temp file with explicit 0600 permissions
f, err := r.fileSystem.OpenFile(tempFilePath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, SSHConfigPerms)
if err != nil {
return "", err
}
if cerr := f.Close(); cerr != nil {
r.logger.Warnf("failed to close temporary file %s: %v", tempFilePath, cerr)
}
return tempFilePath, nil
}