Files
hetzner-api-dyndns-records-…/internal/config/config.go
T
admin f02ec9977c
Container-Image veröffentlichen / container (push) Has been cancelled
feat: add resilient updates and access controls
2026-08-28 14:02:07 +02:00

122 lines
3.7 KiB
Go

package config
import (
"errors"
"fmt"
"net"
"net/url"
"os"
"path/filepath"
"strconv"
"strings"
"time"
)
const (
DefaultIPv4Primary = "https://api.ipify.org"
DefaultIPv4Fallback = "https://ifconfig.co/ip"
DefaultIPv6Primary = "https://api6.ipify.org"
DefaultIPv6Fallback = "https://ifconfig.co/ip"
)
type Config struct {
Address string
DataDir string
DatabasePath string
MasterKeyFile string
CookieSecure bool
SessionTTL time.Duration
HCloudBaseURL string
Mode string
ShutdownTimeout time.Duration
UpdateAPIURL string
UpdateAgentSock string
UpdateInterval time.Duration
}
func Load() (Config, error) {
dataDir := value("APP_DATA_DIR", "/data")
address := value("APP_ADDRESS", ":8080")
if _, _, err := net.SplitHostPort(address); err != nil {
return Config{}, fmt.Errorf("APP_ADDRESS must be host:port: %w", err)
}
mode := strings.ToLower(value("APP_MODE", "lan"))
if mode != "lan" && mode != "https" {
return Config{}, fmt.Errorf("APP_MODE must be either lan or https")
}
ttl, err := duration("APP_SESSION_TTL", 8*time.Hour)
if err != nil || ttl < time.Hour || ttl > 7*24*time.Hour {
return Config{}, fmt.Errorf("APP_SESSION_TTL must be between 1h and 168h")
}
shutdownTimeout, err := duration("APP_SHUTDOWN_TIMEOUT", 15*time.Second)
if err != nil {
return Config{}, fmt.Errorf("APP_SHUTDOWN_TIMEOUT: %w", err)
}
keyFile := value("APP_MASTER_KEY_FILE", "/secrets/master_key")
updateInterval, err := duration("APP_SOFTWARE_UPDATE_CHECK_INTERVAL", 6*time.Hour)
if err != nil || updateInterval < 15*time.Minute || updateInterval > 7*24*time.Hour {
return Config{}, fmt.Errorf("APP_SOFTWARE_UPDATE_CHECK_INTERVAL must be between 15m and 168h")
}
updateAPIURL := value("APP_SOFTWARE_UPDATE_API_URL", "https://git.j-mahler.de/api/v1/repos/admin/hetzner-api-dyndns-records-webinterface/releases/latest")
if err := validateUpdateURL(updateAPIURL); err != nil {
return Config{}, fmt.Errorf("APP_SOFTWARE_UPDATE_API_URL: %w", err)
}
cookieSecure := mode == "https"
if raw := os.Getenv("APP_COOKIE_SECURE"); raw != "" {
parsed, parseErr := strconv.ParseBool(raw)
if parseErr != nil {
return Config{}, fmt.Errorf("APP_COOKIE_SECURE: %w", parseErr)
}
cookieSecure = parsed
}
return Config{
Address: address,
DataDir: dataDir,
DatabasePath: value("APP_DATABASE_PATH", filepath.Join(dataDir, "dyndns.db")),
MasterKeyFile: keyFile,
CookieSecure: cookieSecure,
SessionTTL: ttl,
HCloudBaseURL: strings.TrimRight(value("APP_HCLOUD_BASE_URL", "https://api.hetzner.cloud/v1"), "/"),
Mode: mode,
ShutdownTimeout: shutdownTimeout,
UpdateAPIURL: updateAPIURL,
UpdateAgentSock: value("APP_SOFTWARE_UPDATE_AGENT_SOCKET", "/run/domain-control-update/agent.sock"),
UpdateInterval: updateInterval,
}, nil
}
func validateUpdateURL(raw string) error {
parsed, err := url.Parse(raw)
if err != nil || parsed.Host == "" || parsed.User != nil || (parsed.Scheme != "https" && parsed.Scheme != "http") {
return errors.New("must be an absolute HTTPS URL without embedded credentials")
}
if parsed.Scheme == "https" {
return nil
}
host := parsed.Hostname()
address := net.ParseIP(host)
if host == "localhost" || (address != nil && address.IsLoopback()) {
return nil
}
return errors.New("HTTP is allowed only for loopback test endpoints")
}
func value(name, fallback string) string {
if v := strings.TrimSpace(os.Getenv(name)); v != "" {
return v
}
return fallback
}
func duration(name string, fallback time.Duration) (time.Duration, error) {
if raw := strings.TrimSpace(os.Getenv(name)); raw != "" {
return time.ParseDuration(raw)
}
return fallback, nil
}