Support loading config from different formats (#228)

infra/conf/serial/builder.go

@@ -0,0 +1,44 @@
+package serial
+
+import (
+	"github.com/xtls/xray-core/core"
+	"github.com/xtls/xray-core/infra/conf"
+	"github.com/xtls/xray-core/main/confloader"
+	"io"
+)
+
+func BuildConfig(files []string, formats []string) (*core.Config, error) {
+
+	cf := &conf.Config{}
+	for i, file := range files {
+		newError("Reading config: ", file).AtInfo().WriteToLog()
+		r, err := confloader.LoadConfig(file)
+		if err != nil {
+			return nil, newError("failed to read config: ", file).Base(err)
+		}
+		c, err := ReaderDecoderByFormat[formats[i]](r)
+		if err != nil {
+			return nil, newError("failed to decode config: ", file).Base(err)
+		}
+		if i == 0 {
+			*cf = *c
+			continue
+		}
+		cf.Override(c, file)
+	}
+	return cf.Build()
+}
+
+type readerDecoder func(io.Reader) (*conf.Config, error)
+
+var (
+	ReaderDecoderByFormat = make(map[string]readerDecoder)
+)
+
+func init() {
+	ReaderDecoderByFormat["json"] = DecodeJSONConfig
+	ReaderDecoderByFormat["yaml"] = DecodeYAMLConfig
+	ReaderDecoderByFormat["toml"] = DecodeTOMLConfig
+
+	core.ConfigBuilderForFiles = BuildConfig
+}