From 6bfcb2e1f551620dab108b2d893bd3dfad93425a Mon Sep 17 00:00:00 2001
From: Kawin Viriyaprasopsook <kawin.v@extend-it-resource.com>
Date: Mon, 22 Jul 2024 15:26:58 +0700
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=EF=B8=8F=20slices.SortFunc=20for=20up?=
 =?UTF-8?q?streams?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/mod/utils/utils.go | 52 ++++++++++++++++++++++++------------------
 src/upstreams.go       | 20 ++++++++--------
 2 files changed, 40 insertions(+), 32 deletions(-)

diff --git a/src/mod/utils/utils.go b/src/mod/utils/utils.go
index a61d5ed..21d2e40 100644
--- a/src/mod/utils/utils.go
+++ b/src/mod/utils/utils.go
@@ -41,12 +41,12 @@ func SendOK(w http.ResponseWriter) {
 
 // Get GET parameter
 func GetPara(r *http.Request, key string) (string, error) {
-	keys, ok := r.URL.Query()[key]
-	if !ok || len(keys[0]) < 1 {
+	// Get first value from the URL query
+	value := r.URL.Query().Get(key)
+	if len(value) == 0 {
 		return "", errors.New("invalid " + key + " given")
-	} else {
-		return keys[0], nil
 	}
+	return value, nil
 }
 
 // Get GET paramter as boolean, accept 1 or true
@@ -56,26 +56,29 @@ func GetBool(r *http.Request, key string) (bool, error) {
 		return false, err
 	}
 
-	x = strings.TrimSpace(x)
-
-	if x == "1" || strings.ToLower(x) == "true" || strings.ToLower(x) == "on" {
+	// Convert to lowercase and trim spaces just once to compare
+	switch strings.ToLower(strings.TrimSpace(x)) {
+	case "1", "true", "on":
 		return true, nil
-	} else if x == "0" || strings.ToLower(x) == "false" || strings.ToLower(x) == "off" {
+	case "0", "false", "off":
 		return false, nil
 	}
 
 	return false, errors.New("invalid boolean given")
 }
 
-// Get POST paramter
+// Get POST parameter
 func PostPara(r *http.Request, key string) (string, error) {
-	r.ParseForm()
-	x := r.Form.Get(key)
-	if x == "" {
-		return "", errors.New("invalid " + key + " given")
-	} else {
-		return x, nil
+	// Try to parse the form
+	if err := r.ParseForm(); err != nil {
+		return "", err
 	}
+	// Get first value from the form
+	x := r.Form.Get(key)
+	if len(x) == 0 {
+		return "", errors.New("invalid " + key + " given")
+	}
+	return x, nil
 }
 
 // Get POST paramter as boolean, accept 1 or true
@@ -85,11 +88,11 @@ func PostBool(r *http.Request, key string) (bool, error) {
 		return false, err
 	}
 
-	x = strings.TrimSpace(x)
-
-	if x == "1" || strings.ToLower(x) == "true" || strings.ToLower(x) == "on" {
+	// Convert to lowercase and trim spaces just once to compare
+	switch strings.ToLower(strings.TrimSpace(x)) {
+	case "1", "true", "on":
 		return true, nil
-	} else if x == "0" || strings.ToLower(x) == "false" || strings.ToLower(x) == "off" {
+	case "0", "false", "off":
 		return false, nil
 	}
 
@@ -114,14 +117,19 @@ func PostInt(r *http.Request, key string) (int, error) {
 
 func FileExists(filename string) bool {
 	_, err := os.Stat(filename)
-	if os.IsNotExist(err) {
+	if err == nil {
+		// File exists
+		return true
+	} else if errors.Is(err, os.ErrNotExist) {
+		// File does not exist
 		return false
 	}
-	return true
+	// Some other error
+	return false
 }
 
 func IsDir(path string) bool {
-	if FileExists(path) == false {
+	if !FileExists(path) {
 		return false
 	}
 	fi, err := os.Stat(path)
diff --git a/src/upstreams.go b/src/upstreams.go
index 3ab2eab..c05e645 100644
--- a/src/upstreams.go
+++ b/src/upstreams.go
@@ -1,9 +1,10 @@
 package main
 
 import (
+	"cmp"
 	"encoding/json"
 	"net/http"
-	"sort"
+	"slices"
 	"strings"
 
 	"imuslab.com/zoraxy/mod/dynamicproxy/loadbalance"
@@ -33,19 +34,18 @@ func ReverseProxyUpstreamList(w http.ResponseWriter, r *http.Request) {
 
 	activeUpstreams := targetEndpoint.ActiveOrigins
 	inactiveUpstreams := targetEndpoint.InactiveOrigins
-	// Sort the upstreams slice by weight, then by origin domain alphabetically
-	sort.Slice(activeUpstreams, func(i, j int) bool {
-		if activeUpstreams[i].Weight != activeUpstreams[j].Weight {
-			return activeUpstreams[i].Weight > activeUpstreams[j].Weight
+	slices.SortFunc(activeUpstreams, func(i, j *loadbalance.Upstream) int {
+		if i.Weight != j.Weight {
+			return cmp.Compare(j.Weight, i.Weight)
 		}
-		return activeUpstreams[i].OriginIpOrDomain < activeUpstreams[j].OriginIpOrDomain
+		return cmp.Compare(i.OriginIpOrDomain, j.OriginIpOrDomain)
 	})
 
-	sort.Slice(inactiveUpstreams, func(i, j int) bool {
-		if inactiveUpstreams[i].Weight != inactiveUpstreams[j].Weight {
-			return inactiveUpstreams[i].Weight > inactiveUpstreams[j].Weight
+	slices.SortFunc(inactiveUpstreams, func(i, j *loadbalance.Upstream) int {
+		if i.Weight != j.Weight {
+			return cmp.Compare(j.Weight, i.Weight)
 		}
-		return inactiveUpstreams[i].OriginIpOrDomain < inactiveUpstreams[j].OriginIpOrDomain
+		return cmp.Compare(i.OriginIpOrDomain, j.OriginIpOrDomain)
 	})
 
 	type UpstreamCombinedList struct {