chore(config): upgrade to gosettings v0.4.0

- drop qdm12/govalid dependency
- upgrade qdm12/ss-server to v0.6.0
- do not unset sensitive config settings (makes no sense to me)

internal/configuration/sources/files/reader.go

@@ -1,32 +1,99 @@
 package files
 
 import (
-	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"os"
+	"path/filepath"
+	"strings"
 )
 
 type Source struct {
-	wireguardConfigPath string
+	rootDirectory string
+	environ       map[string]string
+	warner        Warner
+	cached        struct {
+		wireguardLoaded bool
+		wireguardConf   WireguardConfig
+	}
 }
 
-func New() *Source {
-	const wireguardConfigPath = "/gluetun/wireguard/wg0.conf"
+func New(warner Warner) (source *Source) {
+	osEnviron := os.Environ()
+	environ := make(map[string]string, len(osEnviron))
+	for _, pair := range osEnviron {
+		const maxSplit = 2
+		split := strings.SplitN(pair, "=", maxSplit)
+		environ[split[0]] = split[1]
+	}
+
 	return &Source{
-		wireguardConfigPath: wireguardConfigPath,
+		rootDirectory: "/gluetun",
+		environ:       environ,
+		warner:        warner,
 	}
 }
 
 func (s *Source) String() string { return "files" }
 
-func (s *Source) Read() (settings settings.Settings, err error) {
-	settings.VPN, err = s.readVPN()
-	if err != nil {
-		return settings, err
+func (s *Source) Get(key string) (value string, isSet bool) {
+	if key == "" {
+		return "", false
+	}
+	// TODO v4 custom environment variable to set the files parent directory
+	// and not to set each file to a specific path
+	envKey := strings.ToUpper(key)
+	envKey = strings.ReplaceAll(envKey, "-", "_")
+	envKey += "_FILE"
+	path := s.environ[envKey]
+	if path == "" {
+		path = filepath.Join(s.rootDirectory, key)
 	}
 
-	settings.System, err = s.readSystem()
-	if err != nil {
-		return settings, err
+	// Special file handling
+	switch key {
+	// TODO timezone from /etc/localtime
+	case "client.crt", "client.key":
+		value, isSet, err := ReadPEMFile(path)
+		if err != nil {
+			s.warner.Warnf("skipping %s: parsing PEM: %s", path, err)
+		}
+		return value, isSet
+	case "wireguard_private_key":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().PrivateKey)
+	case "wireguard_preshared_key":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().PreSharedKey)
+	case "wireguard_addresses":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().Addresses)
+	case "wireguard_public_key":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().PublicKey)
+	case "vpn_endpoint_ip":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().EndpointIP)
+	case "vpn_endpoint_port":
+		return strPtrToStringIsSet(s.lazyLoadWireguardConf().EndpointPort)
 	}
 
-	return settings, nil
+	value, isSet, err := ReadFromFile(path)
+	if err != nil {
+		s.warner.Warnf("skipping %s: reading file: %s", path, err)
+	}
+	return value, isSet
+}
+
+func (s *Source) KeyTransform(key string) string {
+	switch key {
+	// TODO v4 remove these irregular cases
+	case "OPENVPN_KEY":
+		return "client.key"
+	case "OPENVPN_CERT":
+		return "client.crt"
+	default:
+		key = strings.ToLower(key) // HTTPROXY_USER -> httpproxy_user
+		return key
+	}
+}
+
+func strPtrToStringIsSet(ptr *string) (s string, isSet bool) {
+	if ptr == nil {
+		return "", false
+	}
+	return *ptr, true
 }