Geodata: Support automatically updating .dat files and hot reloading (#5992)

https://github.com/XTLS/Xray-core/pull/5992#issuecomment-4320551920

Usage: https://github.com/XTLS/Xray-core/pull/5992#issuecomment-4291168039

infra/conf/geodata.go

@@ -0,0 +1,71 @@
+package conf
+
+import (
+	"net/url"
+
+	"github.com/robfig/cron/v3"
+	"github.com/xtls/xray-core/app/geodata"
+	"github.com/xtls/xray-core/common/errors"
+	"github.com/xtls/xray-core/common/platform/filesystem"
+	"google.golang.org/protobuf/proto"
+)
+
+type GeodataAssetConfig struct {
+	URL  string `json:"url"`
+	File string `json:"file"`
+}
+
+func (c *GeodataAssetConfig) Build() (*geodata.Asset, error) {
+	if err := validateHTTPS(c.URL); err != nil {
+		return nil, errors.New("invalid geodata asset url: ", c.URL).Base(err)
+	}
+	if _, err := filesystem.StatAsset(c.File); err != nil {
+		return nil, errors.New("invalid geodata asset file: ", c.File).Base(err)
+	}
+	return &geodata.Asset{
+		Url:  c.URL,
+		File: c.File,
+	}, nil
+}
+
+func validateHTTPS(s string) error {
+	u, err := url.ParseRequestURI(s)
+	if err != nil {
+		return err
+	}
+	if u.Scheme != "https" || u.Host == "" {
+		return errors.New("scheme must be https")
+	}
+	return nil
+}
+
+type GeodataConfig struct {
+	Cron     *string               `json:"cron"`
+	Outbound string                `json:"outbound"`
+	Assets   []*GeodataAssetConfig `json:"assets"`
+}
+
+func (c *GeodataConfig) Build() (proto.Message, error) {
+	config := &geodata.Config{}
+
+	if c.Cron != nil {
+		if _, err := cron.ParseStandard(*c.Cron); err != nil {
+			return nil, errors.New("invalid geodata cron").Base(err)
+		}
+		config.Cron = *c.Cron
+	}
+
+	config.Outbound = c.Outbound
+
+	assets := make([]*geodata.Asset, 0, len(c.Assets))
+	for _, asset := range c.Assets {
+		built, err := asset.Build()
+		if err != nil {
+			return nil, err
+		}
+		assets = append(assets, built)
+	}
+	config.Assets = assets
+
+	return config, nil
+}