Added load balance origin picker

+ Added load balance picker
+ Added fallback mode for upstream
+ Added stick session

src/mod/update/update.go

@@ -9,21 +9,52 @@ package update
 
 import (
 	"fmt"
+	"os"
 	"strconv"
 	"strings"
 
 	v308 "imuslab.com/zoraxy/mod/update/v308"
+	"imuslab.com/zoraxy/mod/utils"
 )
 
 // Run config update. Version numbers are int. For example
 // to update 3.0.7 to 3.0.8, use RunConfigUpdate(307, 308)
 // This function support cross versions updates (e.g. 307 -> 310)
 func RunConfigUpdate(fromVersion int, toVersion int) {
+	versionFile := "./conf/version"
+	if fromVersion == 0 {
+		//Run auto previous version detection
+		fromVersion = 307
+		if utils.FileExists(versionFile) {
+			//Read the version file
+			previousVersionText, err := os.ReadFile(versionFile)
+			if err != nil {
+				panic("Unable to read version file at " + versionFile)
+			}
+
+			//Convert the version to int
+			versionInt, err := strconv.Atoi(strings.TrimSpace(string(previousVersionText)))
+			if err != nil {
+				panic("Unable to read version file at " + versionFile)
+			}
+
+			fromVersion = versionInt
+		}
+
+		if fromVersion == toVersion {
+			//No need to update
+			return
+		}
+	}
+
+	//Do iterate update
 	for i := fromVersion; i < toVersion; i++ {
 		oldVersion := fromVersion
 		newVersion := fromVersion + 1
 		fmt.Println("Updating from v", oldVersion, " to v", newVersion)
 		runUpdateRoutineWithVersion(oldVersion, newVersion)
+		//Write the updated version to file
+		os.WriteFile(versionFile, []byte(strconv.Itoa(newVersion)), 0775)
 	}
 	fmt.Println("Update completed")
 }
@@ -36,6 +67,7 @@ func GetVersionIntFromVersionNumber(version string) int {
 
 func runUpdateRoutineWithVersion(fromVersion int, toVersion int) {
 	if fromVersion == 307 && toVersion == 308 {
+		//Updating from v3.0.7 to v3.0.8
 		err := v308.UpdateFrom307To308()
 		if err != nil {
 			panic(err)