chore(sources/env): bump gosettings to v0.3.0-rc13

- Use `RetroKeys` option with env.* method calls
- Use `CSV*` typed methods
- Inject `handleDeprecatedKey` function

internal/configuration/sources/env/shadowsocks.go

@@ -1,6 +1,8 @@
 package env
 
 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gosettings/sources/env"
 )
@@ -11,35 +13,30 @@ func (s *Source) readShadowsocks() (shadowsocks settings.Shadowsocks, err error)
 		return shadowsocks, err
 	}
 
-	shadowsocks.Address = s.readShadowsocksAddress()
+	shadowsocks.Address, err = s.readShadowsocksAddress()
+	if err != nil {
+		return shadowsocks, err
+	}
 	shadowsocks.LogAddresses, err = s.env.BoolPtr("SHADOWSOCKS_LOG")
 	if err != nil {
 		return shadowsocks, err
 	}
-	shadowsocks.CipherName = s.readShadowsocksCipher()
+	shadowsocks.CipherName = s.env.String("SHADOWSOCKS_CIPHER",
+		env.RetroKeys("SHADOWSOCKS_METHOD"))
 	shadowsocks.Password = s.env.Get("SHADOWSOCKS_PASSWORD", env.ForceLowercase(false))
 
 	return shadowsocks, nil
 }
 
-func (s *Source) readShadowsocksAddress() (address *string) {
-	key, value := s.getEnvWithRetro("SHADOWSOCKS_LISTENING_ADDRESS",
-		[]string{"SHADOWSOCKS_PORT"})
-	if value == nil {
-		return nil
+func (s *Source) readShadowsocksAddress() (address *string, err error) {
+	const currentKey = "SHADOWSOCKS_LISTENING_ADDRESS"
+	port, err := s.env.Uint16Ptr("SHADOWSOCKS_PORT") // retro-compatibility
+	if err != nil {
+		return nil, err
+	} else if port != nil {
+		s.handleDeprecatedKey("SHADOWSOCKS_PORT", currentKey)
+		return ptrTo(fmt.Sprintf(":%d", *port)), nil
 	}
 
-	if key == "SHADOWSOCKS_LISTENING_ADDRESS" {
-		return value
-	}
-
-	// Retro-compatibility
-	*value = ":" + *value
-	return value
-}
-
-func (s *Source) readShadowsocksCipher() (cipher string) {
-	envKey, _ := s.getEnvWithRetro("SHADOWSOCKS_CIPHER",
-		[]string{"SHADOWSOCKS_METHOD"})
-	return s.env.String(envKey)
+	return s.env.Get(currentKey), nil
 }